77 results on '"Chuanchuen R"'
Search Results
2. Antimicrobial resistance of Campylobacter coli isolates from swine
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Ekkapobyotin, C., Padungtod, P., and Chuanchuen, R.
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- 2008
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Catalog
3. REVIEW of the Literature on Antimicrobial Resistance in Zoonotic Bacteria from Livestock in East, South and Southeast Asia
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Chuanchuen R, Pariyotorn N
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- 2014
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4. Antimicrobial Resistance Genes among Salmonella enterica isolates from Poultry and Swine in Thailand
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Chuanchuen, R., primary, Padungtod, P., additional, and Pathanasophon, P., additional
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- 2008
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5. Mechanism of Antimicrobial Resistance in Escherochia coli and Salmonella from Food Animals in Thailand
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Padungtod, P., primary, Tribuddharat, C., additional, and Chuanchuen, R., additional
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- 2008
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6. Perspectives on antimicrobial resistance in livestock and livestock products in ASEAN countries
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Archawakulathep, A., Thi Kim, C. T., Meunsene, D., Handijatno, D., Hassim, H., Rovira, H. R. G., Myint, K. S., Baldrias, L. R., Sothy, M., Aung, M., Wahyu, N. H., Rortana Chea, Boonmasawai, S., Vannamahaxay, S., Angkititrakul, S., Collantes, T. M. A., Van, T.N., Punyapornwithaya, V., Zakaria, Z., and Chuanchuen, R. more...
7. Redefining cross-resistance, co-resistance and co-selection: beyond confusion?
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Simjee S, Weese JS, Singh R, Trott DJ, Essack S, Chuanchuen R, and Mehrotra S
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- Humans, Anti-Bacterial Agents pharmacology, Animals, Drug Resistance, Multiple, Bacterial, World Health Organization, Selection, Genetic, Terminology as Topic
- Abstract
The similarity of current definitions of 'cross-resistance' and 'co-resistance' continues to cause confusion both in the scientific community as well as in understanding policies and in particular when looking at resistance from a risk assessment perspective. Further, lack of harmonized definitions of these terms in the regulatory space is challenging for interpretation. The purpose of this article is to: (i) provide an overview of the ambiguity in existing terminology related to cross-resistance, co-resistance and co-selection; (ii) emphasize the challenges created by the use of poor terminology in research and scientific literature; and (iii) propose a clear set of harmonized definitions that could be put into use through international regulatory agencies and institutions, such as the World Health Organization, Food and Drug Administration, European Medicines Agency, Center for Disease Control, Committee for Veterinary Medicinal Products, World Organization for Animal Health/Office International des Epizooties and the Food and Agriculture Organization of the United Nations., (© The Author(s) 2024. Published by Oxford University Press on behalf of British Society for Antimicrobial Chemotherapy. All rights reserved. For commercial re-use, please contact reprints@oup.com for reprints and translation rights for reprints. All other permissions can be obtained through our RightsLink service via the Permissions link on the article page on our site—for further information please contact journals.permissions@oup.com.) more...
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- 2024
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8. Meat ducks as carriers of antimicrobial-resistant Escherichia coli harboring transferable R plasmids.
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Baqar Z, Sinwat N, Prathan R, and Chuanchuen R
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- Animals, Plasmids genetics, Drug Resistance, Bacterial genetics, Escherichia coli Infections veterinary, Escherichia coli Infections microbiology, Drug Resistance, Multiple, Bacterial genetics, Poultry Diseases microbiology, Microbial Sensitivity Tests, R Factors genetics, Gene Transfer, Horizontal, Ducks, Escherichia coli genetics, Escherichia coli drug effects, Anti-Bacterial Agents pharmacology
- Abstract
Importance: Antimicrobial resistance (AMR) is a serious public health threat. AMR bacteria and their resistance determinants in food can be transmitted to humans through the food chain and by direct contact and disseminate directly to the environment., Objective: This study examined the AMR characteristics and transferable R plasmids in Escherichia coli isolated from meat ducks raised in an open-house system., Methods: One hundred seventy-seven (n = 177) commensal E. coli were examined for their antimicrobial susceptibilities and horizontal resistance transfer. The plasmids were examined by PCR-based plasmid replicon typing (PBRT) and plasmid multi-locus sequence typing (pMLST)., Results: The highest resistance rate was found against ampicillin (AMP, 83.0%) and tetracycline (TET, 81.9%), and most isolates exhibited multidrug resistance (MDR) (86.4%). The R plasmids were conjugally transferred when TET (n = 4), AMP (n = 3), and chloramphenicol (n = 3) were used as a selective pressure. The three isolates transferred resistance genes either in AMP or TET. The bla CTX-M1 gene resided on conjugative plasmids. Five replicon types were identified, of which Inc FrepB was most common in the donors (n = 13, 38.4%) and transconjugants (n = 16, 31.2%). Subtyping F plasmids revealed five distinct replicons combinations, including F47:A-:B- (n = 2), F29:A-:B23 (n = 1), F29:A-:B- (n = 1), F18:A-B:- (n = 1), and F4:A-:B- (n = 1). The chloramphenicol resistance was significantly correlated with the other AMR phenotypes ( p < 0.05)., Conclusions and Relevance: The meat ducks harbored MDR E. coli and played an important role in the environmental dissemination of AMR bacteria and its determinants. This confirms AMR as a health issue, highlighting the need for routine AMR monitoring and surveillance of meat ducks., Competing Interests: The authors declare no conflicts of interest., (© 2024 The Korean Society of Veterinary Science.) more...
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- 2024
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9. Chromosomal and plasmid localization of ileS2 in high-level mupirocin-resistant Staphylococcus pseudintermedius and Staphylococcus aureus isolated from canine and feline origins.
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Chanchaithong P, Chueahiran S, Pinpimai K, Sroithongkham P, Leelapsawas C, Indra R, Yindee J, and Chuanchuen R
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- Animals, Cats microbiology, Dogs microbiology, Cat Diseases microbiology, Dog Diseases microbiology, Drug Resistance, Bacterial genetics, Genome, Bacterial, Interspersed Repetitive Sequences genetics, Methicillin-Resistant Staphylococcus aureus genetics, Methicillin-Resistant Staphylococcus aureus drug effects, Methicillin-Resistant Staphylococcus aureus isolation & purification, Microbial Sensitivity Tests, Phylogeny, Plasmids genetics, Staphylococcal Infections microbiology, Staphylococcal Infections veterinary, Anti-Bacterial Agents pharmacology, Bacterial Proteins genetics, Chromosomes, Bacterial genetics, Mupirocin pharmacology, Staphylococcus genetics, Staphylococcus drug effects, Staphylococcus isolation & purification
- Abstract
Objectives: To characterize the mobile genetic elements and genetic localization of ileS2 in high-level mupirocin-resistant (Hi-MupR) methicillin-resistant Staphylococcus pseudintermedius (MRSP) and MRSA isolates recovered from canine and feline clinical samples., Methods: The identification of bacterial species and presence of mecA and ileS2 genes in MRSP and MRSA isolates were performed using MALDI-TOF MS and PCR, respectively. Antimicrobial resistance (AMR) phenotypes were determined by broth microdilution assays. The genome characteristics, ileS2-containing elements and staphylococcal cassette chromosome mec (SCCmec) were illustrated using complete circular genomes obtained from hybrid assembly of Illumina short-reads and Oxford Nanopore Technologies long-reads. These were analysed through phylogenetic and bioinformatics approaches., Results: A total of 18 MRSP clinical isolates and four MRSA clinical isolates exhibited the Hi-MupR phenotype and carried multiple AMR genes, including mecA and ileS2 genes. MRSP ST182-SCCmec V (n = 6) and ST282-ΨSCCmec57395-t10 (n = 4) contained the ileS2 transposable unit associated with IS257 on the chromosome. Three MRSA ST398-SCCmec V-t034/t4652 isolates carried ∼42 kb pSK41-like ileS2 plasmids, whereas similar ileS2 plasmids lacking tra genes were found in MRSP ST282-ΨSCCmec57395-t72/t21 isolates. Furthermore, a new group of ileS2 plasmids, carried by MRSP ST45-ΨSCCmec57395, ST433-ΨSCCmecKW21-t05 and ST2165-SCCmec IV-t06, and by one MRSA ST398-SCCmec V-t034 strain, shared the plasmid backbone with the cfr/fexA-carrying plasmid pM084526_1 in MRSA ST398., Conclusions: This study provides the first evidence of ileS2 integration into the S. pseudintermedius chromosome, which is a rare occurrence in staphylococcal species, and plasmids played a pivotal role in dissemination of ileS2 in both staphylococcal species., (© The Author(s) 2024. Published by Oxford University Press on behalf of British Society for Antimicrobial Chemotherapy. All rights reserved. For commercial re-use, please contact reprints@oup.com for reprints and translation rights for reprints. All other permissions can be obtained through our RightsLink service via the Permissions link on the article page on our site—for further information please contact journals.permissions@oup.com.) more...
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- 2024
- Full Text
- View/download PDF
10. Metagenomic insights into isolable bacterial communities and antimicrobial resistance in airborne dust from pig farms.
- Author
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Hein ST, Prathan R, Srisanga S, Muenhor D, Wongsurawat T, Jenjaroenpun P, Tummaruk P, and Chuanchuen R
- Abstract
This study aims to investigate bacterial communities and antimicrobial resistance (AMR) in airborne dust from pig farms. Airborne dust, pig feces and feed were collected from nine pig farms in Thailand. Airborne dust samples were collected from upwind and downwind (25 meters from pig house), and inside (in the middle of the pig house) of the selected pig house. Pig feces and feed samples were individually collected from the pen floor and feed trough from the same pig house where airborne dust was collected. A direct total bacteria count on each sampling plate was conducted and averaged. The ESKAPE pathogens together with Escherichia coli, Salmonella , and Streptococcus were examined. A total of 163 bacterial isolates were collected and tested for MICs. Pooled bacteria from the inside airborne dust samples were analyzed using Metagenomic Sequencing. The highest bacterial concentration (1.9-11.2 × 10
3 CFU/m3 ) was found inside pig houses. Staphylococcus ( n = 37) and Enterococcus ( n = 36) were most frequent bacterial species. Salmonella ( n = 3) were exclusively isolated from feed and feces. Target bacteria showed a variety of resistance phenotypes, and the same bacterial species with the same resistance phenotype were found in airborne dust, feed and fecal from each farm. Metagenomic Sequencing analysis revealed 1,652 bacterial species across all pig farms, of which the predominant bacterial phylum was Bacillota. One hundred fifty-nine AMR genes of 12 different antibiotic classes were identified, with aminoglycoside resistance genes (24%) being the most prevalent. A total of 251 different plasmids were discovered, and the same plasmid was detected in multiple farms. In conclusion, the phenotypic and metagenomic results demonstrated that airborne dust from pig farms contained a diverse array of bacterial species and genes encoding resistance to a range of clinically important antimicrobial agents, indicating the significant role in the spread of AMR bacterial pathogens with potential hazards to human health. Policy measurements to address AMR in airborne dust from livestock farms are mandatory., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Hein, Prathan, Srisanga, Muenhor, Wongsurawat, Jenjaroenpun, Tummaruk and Chuanchuen.) more...- Published
- 2024
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11. Molecular basis of the persistence of chloramphenicol resistance among Escherichia coli and Salmonella spp. from pigs, pork and humans in Thailand.
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Puangseree J, Prathan R, Srisanga S, and Chuanchuen R
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- Chloramphenicol pharmacology, Chloramphenicol therapeutic use, Anti-Bacterial Agents pharmacology, Anti-Bacterial Agents therapeutic use, Thailand, Genes, Bacterial, Swine microbiology, Humans, Animals, Pork Meat microbiology, Dipeptides genetics, Dipeptides metabolism, Escherichia coli Proteins genetics, Salmonella, Whole Genome Sequencing, Escherichia coli drug effects, Escherichia coli genetics, Salmonella enterica drug effects, Salmonella enterica genetics, Drug Resistance, Bacterial genetics
- Abstract
This study aimed to investigate the potential mechanisms associated with the persistence of chloramphenicol (CHP) resistance in Escherichia coli and Salmonella enterica isolated from pigs, pork, and humans in Thailand. The CHP-resistant E. coli (n = 106) and Salmonella (n = 57) isolates were tested for their CHP susceptibility in the presence and absence of phenylalanine arginine β-naphthylamide (PAβN). The potential co-selection of CHP resistance was investigated through conjugation experiments. Whole genome sequencing (WGS) was performed to analyze the E. coli (E329, E333, and E290) and Salmonella (SA448, SA461, and SA515) isolates with high CHP MIC (32-256 μg/mL) and predominant plasmid replicon types. The presence of PAβN significantly reduced the CHP MICs (≥4-fold) in most E. coli (67.9%) and Salmonella (64.9%). Ampicillin, tetracycline, and streptomycin co-selected for CHP-resistant Salmonella and E. coli-transconjugants carrying cmlA. IncF plasmids were mostly detected in cmlA carrying Salmonella (IncFIIAs) and E. coli (IncFIB and IncF) transconjugants. The WGS analysis revealed that class1 integrons with cmlA1 gene cassette flanked by IS26 and TnAs1 were located on IncX1 plasmid, IncFIA(HI1)/HI1B plasmids and IncFII/FIB plasmids. IncFIA(HI1)/HI1B/Q1in SA448 contained catA flanked by IS1B and TnAs3. In conclusion, cross resistance through proton motive force-dependent mechanisms and co-selection by other antimicrobial agents involved the persistence of CHP-resistance in E. coli in this collection. Dissemination of CHP-resistance genes was potentially facilitated by mobilization via mobile genetic elements., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2024 Puangseree et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.) more...
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- 2024
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12. Microbiological Quality and Antimicrobial Resistance of Commercial Probiotic Products for Food-Producing Animals.
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Tran HM, Prathan R, Hein ST, and Chuanchuen R
- Abstract
Probiotics have been popularly used in livestock production as an alternative to antibiotics. This study aimed to investigate the microbiological quality and phenotypic and genotypic antimicrobial resistance of bacteria in probiotic products sold for food animals. A total of 45 probiotic products were examined for the number of viable cells, species, and antimicrobial susceptibility; the contamination of Escherichia coli and Salmonella ; and the presence of 112 genes encoding resistance to clinically important antimicrobials and transferability of AMR determinants. The results showed that 29 of 45 products (64.4%) were incorrectly labeled in either number of viable cells or bacterial species. None of the tested products were contaminated with E. coli and Salmonella . A total of 33 out of 64 bacterial isolates (51.6%) exhibited resistance to at least one antimicrobial agent. Of the 45 products tested, 16 (35.5%) carried AMR genes. Almost all AMR genes detected in probiotic products were not correlated to the AMR phenotype of probiotic strains formulated in the products. Three streptomycin-resistant Lactobacillus isolates could horizontally transfer their AMR determinants. The findings demonstrated that the probiotic products could serve as reservoirs for the spread of AMR genes and may not yield benefits to animals as claimed. The need for the adequate quality control of probiotic products is highlighted. more...
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- 2024
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13. Evaluating Quality Management and Diagnostics Microbiology Performance Within an International External Quality Assessment (EQA) Program Serving National One Health Sector Reference Laboratories Across Asia: Experience Amid the Coronavirus Disease 2019 (COVID-19) Pandemic.
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Abegaz FA, Dos Santos PT, Mogeni OD, Guarnacci T, Poudyal N, Hong J, Kwon SY, Braae R, Prathan R, Tongkum TL, Kamjumpho W, Chuanchuen R, Marks F, Hendriksen RS, and Holm M
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- Humans, Quality Control, Laboratories, Pandemics prevention & control, Asia, Quality Assurance, Health Care, COVID-19 Testing, One Health, COVID-19, Anti-Infective Agents
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Background: Strengthening external quality assessment (EQA) services across the One Health sector supports implementation of effective antimicrobial resistance (AMR) control strategies. Here we describe and compare 2 different approaches for conducting virtual laboratory follow-up assessments within an EQA program to evaluate quality management system (QMS) and procedures for pathogen identification and antimicrobial susceptibility testing (AST)., Methods: During the coronavirus disease 2019 (COVID-19) pandemic in 2021 and 2022, 2 laboratory assessment approaches were introduced: virtual-based and survey-based methodologies. The evaluation of 2 underperforming Animal Health laboratories through a virtual-based approach occurred between May and August 2021. This evaluation encompassed the utilization of 3 online meetings and document reviews, performed subsequent to the execution of EQA procedures. Within a distinct group of laboratories, the survey-based assessment was implemented from December 2021 to February 2022, also following EQA procedures. This phase encompassed the dissemination of an online survey to 31 participating laboratories, alongside a sole online consultation meeting involving 4 specific underperforming laboratories., Results: The virtual-based assessment post-EQA aimed to identify gaps and areas for improvement in the laboratory's practices for pathogen identification and AST. This approach was, however, time-intensive, and, hence, only 2 laboratories were assessed. In addition, limited interactions in virtual platforms compromised the assessment quality. The survey-based post-EQA assessment enabled evaluation of 31 laboratories. Despite limitations for in-depth analysis of each procedure, gaps in QMS across multiple laboratories were identified and tailored laboratory-specific recommendations were provided., Conclusions: Reliable internet and plans for efficient time management, post-EQA virtual laboratory follow-up assessments are an effective alternative when conducting onsite evaluation is infeasible as observed during the COVID-19 pandemic, although the successful implementation of remediation plans will likely require in person assessments. We advocate application of hybrid approaches (both onsite and virtual) for targeted capacity building of AMR procedures with the ability to implement and oversee the process., Competing Interests: Potential conflicts of interest. The authors: No reported conflicts of interest. All authors have submitted the ICMJE Form for Disclosure of Potential Conflicts of Interest., (© The Author(s) 2023. Published by Oxford University Press on behalf of Infectious Diseases Society of America.) more...
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- 2023
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14. Antimicrobial resistance, Extended-Spectrum β-Lactamase production and virulence genes in Salmonella enterica and Escherichia coli isolates from estuarine environment.
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Jeamsripong S, Kuldee M, Thaotumpitak V, and Chuanchuen R
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- Animals, Humans, Escherichia coli, Anti-Bacterial Agents pharmacology, Virulence genetics, Drug Resistance, Bacterial genetics, beta-Lactamases genetics, Salmonella enterica, Anti-Infective Agents pharmacology, Escherichia coli Infections microbiology
- Abstract
The impact of antimicrobial resistance (AMR) on global public health has been widely documented. AMR in the environment poses a serious threat to both human and animal health but is frequently overlooked. This study aimed to characterize the association between phenotype and genotype of AMR, virulence genes and Extended-Spectrum β-Lactamase (ESBL) production from estuarine environment. The Salmonella (n = 126) and E. coli (n = 409) were isolated from oysters and estuarine water in Thailand. The isolates of Salmonella (96.9%) and E. coli (91.4%) showed resistance to at least one antimicrobial agent. Multidrug resistance (MDR) was 40.1% of Salmonella and 23.0% of E. coli. Resistance to sulfamethoxazole was most common in Salmonella (95.2%) and E. coli (77.8%). The common resistance genes found in Salmonella were sul3 (14.3%), followed by blaTEM (11.9%), and cmlA (11.9%), while most E. coli were blaTEM (31.5%) and tetA (25.4%). The ESBL production was detected in Salmonella (1.6%, n = 2) of which one isolate was positive to blaTEM-1. Eight E. coli isolates (2.0%) were ESBL producers, of which three isolates carried blaCTX-M-55 and one isolate was blaTEM-1. Predominant virulence genes identified in Salmonella were invA (77.0%), stn (77.0%), and fimA (69.0%), while those in E. coli isolates were stx1 (17.8%), lt (11.7%), and stx2 (1.2%). Logistic regression models showed the statistical association between resistance phenotype, virulence genes and ESBL production (p < 0.05). The findings highlighted that estuarine environment were potential hotspots of resistance. One Health should be implemented to prevent AMR bacteria spreading., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2023 Jeamsripong et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.) more...
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- 2023
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15. Genomic characterization of antimicrobial resistance in mcr -carrying ESBL-producing Escherichia coli from pigs and humans.
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Pungpian C, Angkititrakul S, and Chuanchuen R
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- Animals, Anti-Bacterial Agents pharmacology, Colistin pharmacology, Drug Resistance, Bacterial genetics, Escherichia coli, Genomics, Humans, Microbial Sensitivity Tests, Plasmids genetics, Swine, beta-Lactamases genetics, Escherichia coli Infections veterinary, Escherichia coli Proteins genetics
- Abstract
Whole-genome sequencing (WGS) was conducted to characterize mcr -carrying extended-spectrum beta-lactamase (ESBL)-producing Escherichia coli ( n =7). These E. coli isolates originated from two pigs (TH2 and TH3) and two humans (TH8 and TH9) from Thailand, and three pigs from Lao PDR (LA1, LA2 and LA3). Four E. coli sequence types/serotypes - ST6833/H20 (TH2 and TH3), ST48/O160:H40 (TH8 and TH9), ST5708/H45 (LA1) and ST10562/O148:H30 (LA2 and LA3) - were identified. The plasmid replicon type IncF was identified in all isolates. The point mutations Ser31Thr in PmrA and His2Arg in PmrB were found concurrently in all isolates (colistin MIC=4-8 µg ml
-1 ). LA1 contained up to five point mutations in PmrB, and the colistin MIC was not significantly different from that for the other isolates. All mcr-1.1 was located in the IS Apl1-mcr-1-pap2 element, while all mcr-3.1 was located in the Tn As2-mcr-3.1-dgkA- IS Kpn40 element. The mcr-3.1 and blaCTX-M-55 genes were co-localized on the same plasmid, which concurrently contained cml , qnrS1 and tmrB . The blaCTX-M-55 and mcr-3.1 genes were located on conjugative plasmids and could be transferred horizontally under selective pressure from ampicillin or colistin. In conclusion, comprehensive insights into the genomic information of ESBL-producing E. coli harbouring mcr were obtained. As mcr -carrying ESBL-producing E. coli were detected in pigs and humans, a holistic and multisectoral One Health approach is required to contain antimicrobial resistance (AMR). more...- Published
- 2022
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16. Plasmid profile analysis of Escherichia coli and Salmonella enterica isolated from pigs, pork and humans.
- Author
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Puangseree J, Prathan R, Srisanga S, Angkittitrakul S, and Chuanchuen R
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- Animals, Anti-Bacterial Agents pharmacology, Escherichia coli genetics, Humans, Plasmids genetics, Salmonella genetics, Swine, beta-Lactamases genetics, Escherichia coli Infections epidemiology, Escherichia coli Infections veterinary, Pork Meat, Red Meat, Salmonella enterica genetics
- Abstract
This study aimed to determine the epidemiology and association of antimicrobial resistance (AMR) among Escherichia coli and Salmonella in Thailand. The E. coli ( n = 1047) and Salmonella ( n = 816) isolates from pigs, pork and humans were screened for 18 replicons including HI1, HI2, I1- γ , X, L/M, N, FIA, FIB, W, Y, P, FIC, A/C, T, FIIAs, F, K and B/O using polymerase chain reaction-based replicon typing. The E. coli ( n = 26) and Salmonella ( n = 3) isolates carrying IncF family replicons, ESBL and/or mcr genes were determined for FAB formula. IncF represented the major type of plasmids. Sixteen and eleven Inc groups were identified in E. coli (85.3%) and Salmonella (25.7%), respectively. The predominant replicon patterns between E. coli and Salmonella were IncK-F (23.7%) and IncF (46.2%). Significant correlations ( P < 0.05) were observed between plasmid-replicon type and resistance phenotype. Plasmid replicon types were significantly different among sources of isolates and sampling periods. The most common FAB types between E. coli and Salmonella were F2:A-:B- (30.8%) and S1:A-:B- (66.7%), respectively. In conclusion, various plasmids present in E. coli and Salmonella . Responsible and prudent use of antimicrobials is suggested to reduce the selective pressures that favour the spread of AMR determinants. Further studies to understand the evolution of R plasmids and their contribution to the dissemination of AMR genes are warranted. more...
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- 2022
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17. Plasmid-mediated colistin resistance and ESBL production in Escherichia coli from clinically healthy and sick pigs.
- Author
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Trongjit S, Assavacheep P, Samngamnim S, My TH, An VTT, Simjee S, and Chuanchuen R
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- Animals, Escherichia coli genetics, Escherichia coli isolation & purification, Escherichia coli Infections microbiology, Escherichia coli Proteins genetics, Farms, Feces microbiology, Female, Genes, Bacterial, Genotype, Male, Microbial Sensitivity Tests, Phenotype, Swine, beta-Lactamases genetics, Anti-Bacterial Agents pharmacology, Colistin pharmacology, Drug Resistance, Multiple, Bacterial genetics, Escherichia coli drug effects, Escherichia coli enzymology, Escherichia coli Infections veterinary, Escherichia coli Proteins biosynthesis, Plasmids, Swine Diseases microbiology, beta-Lactamases biosynthesis
- Abstract
This study aimed to determine the percentage of colistin resistant and ESBL-producing Escherichia coli from clinically sick and healthy pigs and understand the molecular mechanisms underlying colistin resistance and ESBL production. A total of 454 E. coli isolates from healthy pigs (n = 354; piglets, n = 83; fattening pigs, n = 142 and sows, n = 100) and sick pigs (n = 100) were examined for antimicrobial susceptibility, chromosomal and plasmid-mediated colistin resistance mechanisms and ESBL genes. The healthy (41%) and sick pig (73%) isolates were commonly resistant to colistin. Three mcr genes including mcr-1 (10.4%), mcr-2 (1.1%) and mcr-3 (45%) were detected, of which mcr-3 was most frequently detected in the healthy (33%) and sick pig (57%) isolates. Coexistence of mcr-1/mcr-3 and mcr-2/mcr-3 was observed in piglets (23%), fattening pig (3.5%) and sick pig (13%) isolates. Three amino acid substitutions including E106A and G144S in PmrA and V161G in PmrB were observed only in colistin-resistant isolates carrying mcr-3. The percentage of ESBL-producing E. coli was significantly higher in the sick pigs (44%) than the healthy pigs (19.2%) (P = 0.00). The bla
CTX-M group was most prevalent (98.5%), of which blaCTX-M-14 (54.5%) and blaCTX-M-55 (42.9%) were predominant. The blaTEM-1 (68.8%) and blaCMY-2 (6.3%) genes were identified in ESBL-producers. All ESBL producers were multidrug resistant and the majority from piglets (97%), fattening pigs (77.3%) and sick pigs (82%) carried mcr gene (s). ESBL producers from piglets (n = 5) and sick pig (n = 1) simultaneously transferred blaTEM-1 (or blaCTX-M-55 ) and mcr-3 to Salmonella. In conclusion, pigs are important reservoirs of colistin-resistant E. coli that also produced ESBLs, highlighting the need for prudent and effective use of antimicrobials in pigs and other food-producing animals., (© 2022. The Author(s).) more...- Published
- 2022
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18. Clinically healthy household dogs and cats as carriers of multidrug-resistant Salmonella enterica with variable R plasmids.
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Chantharothaiphaichit T, Phongaran D, Angkittitrakul S, Aunpromma S, and Chuanchuen R
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- Animals, Anti-Bacterial Agents pharmacology, Microbial Sensitivity Tests, Plasmids genetics, R Factors, Thailand epidemiology, beta-Lactamases genetics, Carrier State veterinary, Cats microbiology, Dogs microbiology, Drug Resistance, Multiple, Bacterial, Salmonella drug effects, Salmonella enterica drug effects, Salmonella enterica genetics
- Abstract
Introduction. Antimicrobial resistance (AMR) is a One Health issue concerning humans, animals and the environment and a unified One Health approach is required to contain this problematic issue. Dogs and cats are popular pet animals and are known to carry many bacterial pathogens that are of public health importance, including Salmonella . However, data on AMR in companion animals is limited. Gap statement. Scant AMR data from bacteria originating from companion animals limits an accurate assessment of the impacts of pet-animal-related AMR on public health. Purpose. This study aimed to phenotypically and genetically investigate AMR in Salmonella isolated from pet dogs and cats in Thailand. Methodology. Salmonella enterica were isolated from pet dogs ( n =159) and cats ( n =19) in Thailand between 2016 and 2019. All isolates were serotyped. Phenotypic and genotypic antimicrobial resistance was examined. PCR-based replicon typing, replicon sequence typing and plasmid multilocus sequence typing were conducted to characterize plasmids. Results. Seventy-seven serovars were identified, with serovars Weltevreden (9.6%) and Stockholm (9.0%) the most common. Most of the isolates (34.3%) were multidrug-resistant. The serovar Stockholm was an ESBL-producer and carried the β-lactamase genes bla
TEM-1 and blaCTX-M-55 . The plasmid-mediated quinolone resistance (PMQR) gene, qnrS, was also detected (10.1%). Class 1 integrons carrying the dfrA12-aadA2 cassette array were most frequent (45.9%). Five plasmid replicon types as IncA/C (0.6%), N (1.1%), IncFIIA (28.7%), IncHI1 (2.2%), and IncI1 (3.4%) were identified. Based on the pMLST typing scheme ( n =9), plasmids were assigned into five different STs including IncA/C-ST6 ( n =1), IncH1-ST16 ( n =4), IncI1-ST3 ( n =1), IncI1-ST60 ( n =1) and IncI1-ST136 ( n =1). The ST 16 of IncHI1 plasmid was a novel plasmid ST. Subtyping F-type plasmids using the RST scheme ( n =9) revealed four different combinations of replicons including S1:A-:B- ( n =4), S1:A-:B22 ( n =2), S3:A-:B- ( n strains with different R plasmid. The implementation of AMR phenotypes instigation and genotypic monitoring and surveillance programmes in companion animals are imperative as integral components of the One Health framework.n =1). Conclusions. Our findings highlight the role of clinically healthy household dogs and cats as carriers of AMR Salmonella strains with different R plasmid. The implementation of AMR phenotypes instigation and genotypic monitoring and surveillance programmes in companion animals are imperative as integral components of the One Health framework. more...- Published
- 2022
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19. Whole genome sequencing and characteristics of Escherichia coli with co-existence of ESBL and mcr genes from pigs.
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Trongjit S and Chuanchuen R
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- Amino Acid Substitution, Animals, Drug Resistance, Bacterial, Escherichia coli genetics, Escherichia coli immunology, Escherichia coli isolation & purification, High-Throughput Nucleotide Sequencing, Interspersed Repetitive Sequences, Phylogeny, Plasmids genetics, Serogroup, Swine, Thailand, Escherichia coli classification, Escherichia coli Infections veterinary, Escherichia coli Proteins genetics, Swine Diseases microbiology, Whole Genome Sequencing methods
- Abstract
This study aimed to analyze three ESBL-producing E. coli co-harboring mcr and ESBL genes from a healthy fattening pig (E. 431) and two sick pigs (ECP.81 and ECP.82) in Thailand using Whole Genome Sequencing (WGS) using either Illumina MiSeq or HiSeq PE150 platforms to determine their genome and transmissible plasmids. E. 431 carrying mcr-2.1 and mcr-3.1 belonged to serotype O142:H31 with ST29 sequence type. ECP.81 and ECP.82 from sick pigs harboring mcr-1.1 and mcr-3.1 were serotype O9:H9 with ST10. Two mcr-1.1 gene cassettes from ECP.81 and ECP.82 were located on IncI2 plasmid with 98% identity to plasmid pHNSHP45. The mcr-2.1-carrying contig in E. 431 showed 100% identity to plasmid pKP37-BE with the upstream flanking sequence of IS1595. All three mcr-3.1-carrying contigs contained the ΔTnAs2-mcr-3.1-dgkA core segment and had high nucleotide similarity (85-100%) to mcr-3.1-carrying plasmid, pWJ1. The mobile elements i.e. IS4321, ΔTnAs2, ISKpn40 and IS3 were identified in the flanking regions of mcr-3. Several genes conferring resistance to aminoglycosides (aac(3)-IIa, aadA1, aadA2b, aph(3'')-Ib, aph(3')-IIa and aph(6)-Id), macrolides (mdf(A)), phenicols (cmlA1), sulphonamide (sul3) and tetracycline (tet(A) and tet(M)) were located on plasmids, of which their presence was well corresponded to the host's resistance phenotype. Amino acid substitutions S83L and D87G in GyrA and S80I and E62K in ParC were observed. The blaCTX-M-14 and blaCTX-M-55 genes were identified among these isolates additionally harbored blaTEM-1B. Co-transfer of mcr-1.1/blaTEM-1B and mcr-3.1/blaCTX-M-55 was observed in ECP.81 and ECP.82 but not located on the same plasmid. The results highlighted that application of advanced innovation technology of WGS in AMR monitoring and surveillance provide comprehensive information of AMR genotype that could yield invaluable benefits to development of control and prevention strategic actions plan for AMR., Competing Interests: The authors have declared that no competing interests exist. more...
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- 2021
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20. Insight Into Whole Genome of Aeromonas veronii Isolated From Freshwater Fish by Resistome Analysis Reveal Extensively Antibiotic Resistant Traits.
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Sakulworakan R, Chokmangmeepisarn P, Dinh-Hung N, Sivaramasamy E, Hirono I, Chuanchuen R, Kayansamruaj P, and Rodkhum C
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Aeromonas veronii outbreaks in tilapia farming caused relatively high mortalities, and the bacteria was resistant to many kinds of antimicrobials used in Thailand aquaculture. According to the CLSI standard, the determination of antimicrobials efficacy has been limited to phenotypic analyses, and a genomics study is required. This research aimed to analyze the resistome of A. veronii isolated from diseased tilapia in Chainat, Nong Khai, and Uttaradit provinces in Thailand. A total of 12 isolates of A. veronii were identified based on the gyrB sequencing and then, the MIC values to eight antimicrobials (AMP, AML, GEN, ENR, OXO, OTC, SXT, and FFC) were determined. According to the MIC patterns, whole genome sequencing (WGS) of five representatives and resistome analysis were performed, including 15 genomes of A. veronii isolated from freshwater fish available in the NCBI. All tilapia isolates were susceptible to FFC but resistant to AML and AMP while OTC resistance was the most dominant. In addition to the WGS analysis, 4.5 Mbp of A. veronii was characterized. A total of 20 ARGs were detected by resistome analysis and 16 genes were shared among the A. veronii population. In conclusion, A. veronii strains isolated from tilapia exhibited a resistance to several antimicrobials and multidrug resistance (MDR) which was related to the presence of multiple ARGs. Aeromonas veronii shared the ARGs in their population worldwide with a possibility of a plasmid-mediated acquisition due to the presence of resistance islands., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Sakulworakan, Chokmangmeepisarn, Dinh-Hung, Sivaramasamy, Hirono, Chuanchuen, Kayansamruaj and Rodkhum.) more...
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- 2021
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21. Dynamics of the fecal microbiome and antimicrobial resistome in commercial piglets during the weaning period.
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Suriyaphol P, Chiu JKH, Yimpring N, Tunsagool P, Mhuantong W, Chuanchuen R, Bessarab I, Williams RBH, Ong RT, and Suriyaphol G
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- Age Factors, Animals, Biodiversity, Metagenome, Metagenomics methods, Swine, Anti-Bacterial Agents pharmacology, Feces microbiology, Microbiota drug effects, Weaning
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This study aimed to characterize the alteration of the fecal microbiome and antimicrobial resistance (AMR) determinants in 24 piglets at day 3 pre-weaning (D. - 3), weaning day (D.0), days 3 (D.3) and 8 post-weaning (D.8), using whole-genome shotgun sequencing. Distinct clusters of microbiomes and AMR determinants were observed at D.8 when Prevotella (20.9%) was the major genus, whereas at D. - 3-D.3, Alistipes (6.9-12.7%) and Bacteroides (5.2-8.5%) were the major genera. Lactobacillus and Escherichia were notably observed at D. - 3 (1.2%) and D. - 3-D.3 (0.2-0.4%), respectively. For AMR, a distinct cluster of AMR determinants was observed at D.8, mainly conferring resistance to macrolide-lincosamide-streptogramin (mefA), β-lactam (cfxA6 and aci1) and phenicol (rlmN). In contrast, at D. - 3-D.3, a high abundance of determinants with aminoglycoside (AMG) (sat, aac(6')-aph(2''), aadA and acrF), β-lactam (fus-1, cepA and mrdA), multidrug resistance (MDR) (gadW, mdtE, emrA, evgS, tolC and mdtB), phenicol (catB4 and cmlA4), and sulfonamide patterns (sul3) was observed. Canonical correlation analysis (CCA) plot associated Escherichia coli with aac(6')-aph(2''), emrA, mdtB, catB4 and cmlA4 at D. - 3, D.0 and/or D.3 whereas at D.8 associations between Prevotella and mefA, cfxA6 and aci1 were identified. The weaning age and diet factor played an important role in the microbial community composition., (© 2021. The Author(s).) more...
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- 2021
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22. Colistin resistance and plasmid-mediated mcr genes in Escherichia coli and Salmonella isolated from pigs, pig carcass and pork in Thailand, Lao PDR and Cambodia border provinces.
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Pungpian C, Lee S, Trongjit S, Sinwat N, Angkititrakul S, Prathan R, Srisanga S, and Chuanchuen R
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- Animals, Cambodia, Escherichia coli genetics, Escherichia coli Proteins metabolism, Laos, Plasmids physiology, Salmonella genetics, Sus scrofa, Thailand, Anti-Bacterial Agents pharmacology, Carbapenems pharmacology, Colistin pharmacology, Drug Resistance, Bacterial genetics, Escherichia coli physiology, Escherichia coli Proteins genetics, Pork Meat microbiology, Salmonella physiology
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Background: Colistin and carbapenem-resistant bacteria have emerged and become a serious public health concern, but their epidemiological data is still limited., Objectives: This study examined colistin and carbapenem resistance in Escherichia coli and Salmonella from pigs, pig carcasses, and pork in Thailand, Lao PDR, and Cambodia border provinces., Methods: The phenotypic and genotypic resistance to colistin and meropenem was determined in E. coli and Salmonella obtained from pigs, pig carcasses, and pork (n = 1,619). A conjugative experiment was performed in all isolates carrying the mcr gene (s) (n = 68). The plasmid replicon type was determined in the isolates carrying a conjugative plasmid with mcr by PCR-based replicon typing (n = 7). The genetic relatedness of mcr -positive Salmonella (n = 11) was investigated by multi-locus sequence typing., Results: Colistin resistance was more common in E. coli (8%) than Salmonella (1%). The highest resistance rate was found in E. coli (17.8%) and Salmonella (1.7%) from Cambodia. Colistin-resistance genes, mcr-1 , mcr-3 , and mcr-5 , were identified, of which mcr-1 and mcr-3 were predominant in E. coli (5.8%) and Salmonella (1.7%), respectively. The mcr-5 gene was observed in E. coli from pork in Cambodia. Two colistin-susceptible pig isolates from Thailand carried both mcr-1 and mcr-3 . Seven E. coli and Salmonella isolates contained mcr-1 or mcr-3 associated with the IncF and IncI plasmids. The mcr -positive Salmonella from Thailand and Cambodia were categorized into two clusters with 94%-97% similarity. None of these clusters was meropenem resistant., Conclusions: Colistin-resistant E. coli and Salmonella were distributed in pigs, pig carcasses, and pork in the border areas. Undivided-One Health collaboration is needed to address the issue., Competing Interests: The authors declare no conflicts of interest., (© 2021 The Korean Society of Veterinary Science.) more...
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- 2021
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23. Metagenomic Survey Reveals More Diverse and Abundant Antibiotic Resistance Genes in Municipal Wastewater Than Hospital Wastewater.
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Zhang D, Peng Y, Chan CL, On H, Wai HK, Shekhawat SS, Gupta AB, Varshney AK, Chuanchuen R, Zhou X, Xia Y, Liang S, Fukuda K, Medicherla KM, and Tun HM
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Alongside antibiotic resistance, co-selection of antibiotics, biocides, and metal resistance is a growing concern. While hospital wastewater is considered a hotspot for antibiotic-resistant bacteria (ARB) and genes (ARGs), the scenario in India, one of the biggest consumers of antibiotics, remains poorly described. In this study, we used metagenomic sequencing to characterize ARGs and biocide/metal resistance genes (BMRGs) in four wastewater treatment plants (WWTPs) in Jaipur City of India. We observed a significantly lower richness and abundance of ARGs in the influent of a WWTP exclusively receiving hospital wastewater when compared to other three WWTPs involving municipal wastewater treatment. Several tetracycline and macrolide-lincosamide-streptogramin resistance genes were enriched in influents of these three municipal wastewater-related treatment plants, whereas hospital wastewater had a higher abundance of genes conferring resistance to disinfectant-related compounds such as synergize and wex-cide-128, reflecting the patterns of antibiotic/disinfectant use. Of note, in the wastewater system with more chemicals, there was a strong correlation between the numbers of ARGs and BMRGs potentially harbored by common hosts. Our study highlights significant influxes of ARGs from non-hospital sources in Jaipur City, and thus more attention should be paid on the emergence of ARGs in general communities., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Zhang, Peng, Chan, On, Wai, Shekhawat, Gupta, Varshney, Chuanchuen, Zhou, Xia, Liang, Fukuda, Medicherla and Tun.) more...
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- 2021
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24. Erratum: Callaway et al. Alternatives to Antibiotics: A Symposium on the Challenges and Solutions for Animal Health and Production. Antibiotics 2021, 10 , 471.
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Callaway TR, Lillehoj H, Chuanchuen R, and Gay CG
- Abstract
The authors would like to make the following corrections to the published paper [...].
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- 2021
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25. Colistin Resistance and ESBL Production in Salmonella and Escherichia coli from Pigs and Pork in the Thailand, Cambodia, Lao PDR, and Myanmar Border Area.
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Lay KK, Jeamsripong S, Sunn KP, Angkititrakul S, Prathan R, Srisanga S, and Chuanchuen R
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The study aimed to examine the prevalence and genetic characteristics of ESBL-production and colistin resistance in Salmonella and Escherichia coli from pigs and pork in the border area among Thailand, Cambodia, Lao PDR, and Myanmar. Salmonella ( n = 463) and E. coli ( n = 767) isolates were collected from pig rectal swab from slaughterhouses ( n = 441) and pork from retail markets ( n = 368) during October 2017 and March 2018. All were determined for susceptibility to colistin and cephalosporins, ESBL production and mcr and ESBL genes. Salmonella was predominantly found in Cambodia (65.8%). Serovars Rissen (35.6%) and Anatum (15.3%) were the most common. The E. coli prevalence in pork was above 91% in all countries. Colistin-resistance rate in E. coli (10.4%) was significantly higher than Salmonella (2.6%). ESBL-producing Salmonella (1.9%) and E. coli (6.3%) were detected. The bla
CTX-M-55 and blaCTX-M-14 were identified. The mcr-1 gene was detected in Salmonella ( n = 12) and E. coli ( n = 68). The mcr-1 / blaCTX-M-55 and mcr-3 / blaCTX-M-55 co-concurrence was observed in one Salmonella and three E. coli isolates, respectively. In conclusion, pigs and pork serve as carriers of colistin and new generation cephalosporins resistance. Testing for resistance to last line antibiotics should be included in national AMR surveillance program using One Health approach. more...- Published
- 2021
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26. Alternatives to Antibiotics: A Symposium on the Challenges and Solutions for Animal Health and Production.
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Callaway TR, Lillehoj H, Chuanchuen R, and Gay CG
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Antibiotics have improved the length and quality of life of people worldwide and have had an immeasurable influence on agricultural animal health and the efficiency of animal production over the last 60 years. The increased affordability of animal protein for a greater proportion of the global population, in which antibiotic use has played a crucial part, has resulted in a substantial improvement in human quality of life. However, these benefits have come with major unintended consequences, including antibiotic resistance. Despite the inherent benefits of restricting antibiotic use in animal production, antibiotics remain essential to ensuring animal health, necessitating the development of novel approaches to replace the prophylactic and growth-promoting benefits of antibiotics. The third International Symposium on "Alternatives to Antibiotics: Challenges and Solutions in Animal Health and Production" in Bangkok, Thailand was organized by the USDA Agricultural Research Service, Faculty of Veterinary Science, Chulalongkorn University and Department of Livestock Development-Thailand Ministry of Agriculture and Cooperative; supported by OIE World Organization for Animal Health; and attended by more than 500 scientists from academia, industry, and government from 32 nations across 6 continents. The focus of the symposium was on ensuring human and animal health, food safety, and improving food animal production efficiency as well as quality. Attendees explored six subject areas in detail through scientific presentations and panel discussions with experts, and the major conclusions were as follows: (1) defining the mechanisms of action of antibiotic alternatives is paramount to enable their effective use, whether they are used for prevention, treatment, or to enhance health and production; (2) there is a need to integrate nutrition, health, and disease research, and host genetics needs to be considered in this regard; (3) a combination of alternatives to antibiotics may need to be considered to achieve optimum health and disease management in different animal production systems; (4) hypothesis-driven field trials with proper controls are needed to validate the safety, efficacy, and return of investment (ROI) of antibiotic alternatives. more...
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- 2021
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27. Metagenomics of antimicrobial and heavy metal resistance in the cecal microbiome of fattening pigs raised without antibiotics.
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Tunsagool P, Mhuantong W, Tangphatsornruang S, Am-In N, Chuanchuen R, Luangtongkum T, and Suriyaphol G
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This study aimed to detect the cecal microbiome, antimicrobial resistance (AMR) and heavy metal resistance genes (MRGs) in fattening pigs raised under antibiotic-free (ABF) conditions compared with ordinary industrial pigs (control, C) using whole-genome shotgun sequencing. ABF pigs showed the enrichment of Prevotella (33%) and Lactobacillus (13%), whereas Escherichia coli (40%), Fusobacterium and Bacteroides (each at 4%) were notably observed in the C group. Distinct clusters of cecal microbiota of ABF and C pigs were revealed; however, microbiota of some C pigs (C1) appeared in the same cluster as ABF and were totally separated from the remaining C pigs (C2). For AMR genes, the highest abundance tet (Q) (35.7%) and mef (A) (12.7%) were markedly observed in the ABF group whereas tet (Q) (26.2%) and tet (W) (10.4%) were shown in the C group. tet (Q) was positively correlated to Prevotella in ABF and C1 samples. In the C2 group, the prominent tet (W) was positively correlated to Fusobacterium and Bacteroides Pigs have never received tetracycline but pregnant sows used chlortetracycline once 7 d before parturition. Chromosomal Cu and Zn resistance genes were also shown in both groups regardless the received Cu and Zn feed additives. A higher abundance of multi-metal resistance genes was observed in the C group (44%) compared with the ABF group (41%). In conclusion, the microbiome clusters in some C pigs were similar to that in ABF pigs. High abundant tetracycline resistance genes interrelated to major bacteria were observed in both ABF and C pigs. MRGs were also observed. IMPORTANCE: Owing to the increased problem of AMR in farm animals, raising farm animals without antibiotics is one method that could solve this problem. Our study showed that only some tetracycline and macrolide resistance genes, tet (Q), tet (W) and mef (A), were markedly abundant in ABF and C groups. The tet (Q) and tet (W) genes interrelated to different predominant bacteria in each group, showing the potential role of major bacteria as reservoirs of AMR genes. In addition, chromosomal Cu and Zn resistance genes were also observed in both pig groups, not depending on the use of Cu and Zn additives in both farms. The association of MRGs and AMR genotypes and phenotypes together with the method to re-sensitize bacteria to antibiotics should be studied further to unveil the cause of high resistance genes and solve the problems., (Copyright © 2021 American Society for Microbiology.) more...
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- 2021
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28. Presence and Transfer of Antimicrobial Resistance Determinants in Escherichia coli in Pigs, Pork, and Humans in Thailand and Lao PDR Border Provinces.
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Pungpian C, Sinwat N, Angkititrakul S, Prathan R, and Chuanchuen R
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- Animals, Humans, Integrons genetics, Laos, Microbial Sensitivity Tests, Plasmids, Swine, Thailand, beta-Lactamases genetics, Anti-Bacterial Agents pharmacology, Drug Resistance, Multiple, Bacterial genetics, Pork Meat microbiology
- Abstract
This study aimed to investigate antimicrobial resistance (AMR) characteristics of Escherichia coli isolates from pig origin (including pigs, pig carcass, and pork) and humans in Thailand and Lao People's Democratic Republic (PDR) border provinces. The majority of the E. coli isolates from Thailand (69.7%) and Lao PDR (63.3%) exhibited multidrug resistance. Class 1 integrons with resistance gene cassettes were common ( n = 43), of which the most predominant resistance gene cassette was aadA1 . The percentage of extended-spectrum beta-lactamase (ESBL) producers was 3.4 in Thailand and 3.2 in Lao PDR. The ESBL genes found were bla
CTX-M14 , blaCTX-M27 , and blaCTX-M55 , of which blaCTX-M55 was the most common (58.6%). Ser-83-Leu and Asp-87-Asn were the predominant amino acid changes in GyrA of ciprofloxacin-resistant isolates. Twenty-two percent of all isolates were positive for qnrS . Class 1 integrons carrying aadA1 from pigs ( n = 1) and ESBL genes ( blaCTX-M55 and blaCTX-M14 ) from pigs ( n = 2), pork ( n = 1), and humans ( n = 7) were located on conjugative plasmids. Most plasmids (29.3%) were typed in the IncFrepB group. In conclusion, AMR E. coli are common in pig origin and humans in these areas. The findings confirm AMR as One Health issue, and highlight the need for comprehensive and unified collaborations within and between sectors on research and policy. more...- Published
- 2021
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29. Rapid detection of extended spectrum β-lactamase producing Escherichia coli isolated from fresh pork meat and pig cecum samples using multiplex recombinase polymerase amplification and lateral flow strip analysis.
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Kanokudom S, Assawakongkarat T, Akeda Y, Ratthawongjirakul P, Chuanchuen R, and Chaichanawongsaroj N
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- Escherichia coli enzymology, Escherichia coli Proteins biosynthesis, beta-Lactamases biosynthesis, Cecum microbiology, Escherichia coli genetics, Escherichia coli isolation & purification, Escherichia coli Proteins genetics, Food Microbiology, Multiplex Polymerase Chain Reaction, Pork Meat microbiology, beta-Lactamases genetics
- Abstract
The emergence and dissemination of extended-spectrum β-lactamase (ESBL)-producing Escherichia coli is a global health issue. Food-producing animals, including pigs, are significant reservoirs of antimicrobial resistance (AMR), which can be transmitted to humans. Thus, the rapid detection of ESBLs is required for efficient epidemiological control and treatment. In this study, multiplex recombinase polymerase amplification (RPA) combined with a single-stranded tag hybridization chromatographic printed-array strip (STH-PAS), as a lateral flow strip assay (LFA), was established for the rapid and simultaneous detection of multiple bla genes in a single reaction. Visible blue lines, indicating the presence of the blaCTX-M, blaSHV, and blaOXA genes, were observed within 10 min by the naked eye. The limit of detection of all three genes was 2.5 ng/25 μL, and no cross-reactivity with seven commensal aerobic bacteria was observed. A total of 93.9% (92/98) and 96% (48/50) of the E. coli isolates from pork meat and fecal samples, respectively, expressed an ESBL-producing phenotype. Nucleotide sequencing of the PCR amplicons showed that blaCTX-M was the most prevalent type (91.3-95.83%), of which the main form was blaCTX-M-55. The sensitivity and specificity of the RPA-LFA were 99.2% and 100%, respectively, and were in almost perfect agreement (κ = 0.949-1.000) with the results from PCR sequencing. Thus, the RPA-LFA is a promising tool for rapid and equipment-free ESBL detection and may facilitate clinical diagnosis in human and veterinary medicine, as well as AMR monitoring and surveillance., Competing Interests: The authors have declared that no competing interests exist. more...
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- 2021
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30. Distribution of phenotypic and genotypic antimicrobial resistance and virulence genes in Vibrio parahaemolyticus isolated from cultivated oysters and estuarine water.
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Jeamsripong S, Khant W, and Chuanchuen R
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- Animals, Anti-Bacterial Agents pharmacology, Drug Resistance, Bacterial genetics, Genotype, Humans, Phenotype, Virulence genetics, Water, Ostreidae, Vibrio parahaemolyticus genetics
- Abstract
A total of 594 Vibrio parahaemolyticus isolates from cultivated oysters (n = 361) and estuarine water (n = 233) were examined for antimicrobial resistance (AMR) phenotype and genotype and virulence genes. Four hundred forty isolates (74.1%) exhibited resistance to at least one antimicrobial agent and 13.5% of the isolates were multidrug-resistant strains. Most of the V. parahaemolyticus isolates were resistant to erythromycin (54.2%), followed by sulfamethoxazole (34.7%) and trimethoprim (27.9%). The most common resistance genes were qnr (77.8%), strB (27.4%) and tet(A) (22.1%), whereas blaTEM (0.8%) was rarely found. Four isolates (0.7%) from oysters (n = 2) and estuarine water (n = 2) were positive to tdh, whereas no trh-positive isolates were observed. Significantly positive associations among AMR genes were observed. The SXT elements and class 1, 2 and 3 integrons were absent in all isolates. The results indicated that V. parahaemolyticus isolates from oysters and estuarine water were potential reservoirs of resistance determinants in the environment. This increasing threat of resistant bacteria in the environment potentially affects human health. A 'One Health' approach involved in multidisciplinary collaborations must be implemented to effectively manage antimicrobial resistance., (© FEMS 2020.) more...
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- 2020
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31. Prevalence, antimicrobial resistance, virulence gene, and class 1 integrons of Enterococcus faecium and Enterococcus faecalis from pigs, pork and humans in Thai-Laos border provinces.
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Thu WP, Sinwat N, Bitrus AA, Angkittitrakul S, Prathan R, and Chuanchuen R
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- Animals, Enterococcus faecalis isolation & purification, Enterococcus faecium isolation & purification, Humans, Integrons genetics, Laos, Microbial Sensitivity Tests, Prevalence, Swine, Thailand, Virulence drug effects, Virulence genetics, Anti-Bacterial Agents pharmacology, Drug Resistance, Multiple, Bacterial genetics, Enterococcus faecalis genetics, Enterococcus faecium genetics, Genes, Bacterial genetics, Molecular Epidemiology, Virulence Factors genetics
- Abstract
Objectives: This study aimed to determine prevalence, antimicrobial resistance, virulence genes, and Class 1 integrons of Enterococcus faecium (E. faecium) and Enterococcus faecalis (E. faecalis) from pigs, pork and humans in Thailand-Laos border provinces., Methods: Six hundred and forty-eight rectal and carcass swab samples from border provinces of Thailand (n=359) and Lao PDR (n=289) were collected and examined from September 2013 to October 2014., Results: The overall prevalence of Enterococcus species was 483 of 648 (75%), comprising E. faecium (359 of 483, 74.3%) and E. faecalis (124 of 483, 25.7%). The occurrence of E. faecium in pigs, pig carcasses, retail pork, and humans in Thailand was 80.6%, 73.8%, 77.6%, and 67%, respectively. The prevalence of E. faecium was higher in Laos (65.7%) than Thailand (47.1%) (P<0.001). Conversely, E. faecalis was more common in Thailand (24.2%) than Laos (12.8%) (P<0.001). The E. faecium and E. faecalis isolates were resistant to all antimicrobials except vancomycin. High resistance was first observed to tetracycline, erythromycin and streptomycin, followed by gentamicin, ampicillin and chloramphenicol. Both E. faecium (7%) and E. faecalis (0.8%) carried empty Class 1 integrons: E. faecium carried gel (6.4%) and esp (0.8%), while E. faecalis carried agg (41.9%), cylA (36.3%), gel (60.5%), and esp (42.7%)., Conclusions: This study revealed a variable distribution of antimicrobial resistance and virulence genes among E. faecium and E. faecalis from pigs, pig products and humans in Thai-Laos border provinces. These pathogens may serve as potential reservoirs for the maintenance and widespread dissemination of antimicrobial resistance and virulence determinants from animals to humans via the food chain., (Copyright © 2019 International Society for Antimicrobial Chemotherapy. Published by Elsevier Ltd. All rights reserved.) more...
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- 2019
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32. Phylogenetic characterization of Salmonella enterica from pig production and humans in Thailand and Laos border provinces.
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Prathan R, Bitrus AA, Sinwat N, Angkititrakul S, and Chuanchuen R
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Background and Aim: The genetic relationship among serotypes of Salmonella enterica from food animals, food of animal origin, and human is of interest as the data could provide an important clue for the source of human infection. This study aimed to determine the genetic relatedness of S. enterica from pig production and human in Thailand-Laos border provinces., Materials and Methods: A total of 195 S. enterica serotypes isolated from pig and pork (n=178) and human (n=17) including four serotypes (Typhimurium, Rissen, Derby, and Stanley) were randomly selected to examine their genetic relatedness using highly conserved sequence of three genes ( fim A, man B, and mdh )., Results: The results showed that 195 Salmonella isolates of four different serotypes were grouped into five different clusters, and members of the same Salmonella serotypes were found in the same cluster. Salmonella isolated from pig production and human in Thailand-Laos border provinces represented overlapping population and revealed a high degree of similarity, indicating close genetic relationship among the isolates., Conclusion: The results support that the determination of Salmonella serotyping combined with analysis of phylogenetic tree can be used track the clonal evolution and genetic diversity of Salmonella serotypes in different host species. more...
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- 2019
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33. Two Regulators, PA3898 and PA2100, Modulate the Pseudomonas aeruginosa Multidrug Resistance MexAB-OprM and EmrAB Efflux Pumps and Biofilm Formation.
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Heacock-Kang Y, Sun Z, Zarzycki-Siek J, Poonsuk K, McMillan IA, Chuanchuen R, and Hoang TT
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- Animals, Bacterial Outer Membrane Proteins genetics, Bacterial Outer Membrane Proteins metabolism, Bacterial Proteins metabolism, Binding Sites, Biofilms, Drosophila melanogaster, Gene Expression Regulation, Bacterial, Male, Membrane Proteins genetics, Membrane Proteins metabolism, Membrane Transport Proteins genetics, Membrane Transport Proteins metabolism, Mice, Inbred BALB C, Microbial Sensitivity Tests, Mutation, Phenazines metabolism, Pseudomonas Infections microbiology, Pseudomonas aeruginosa drug effects, Pseudomonas aeruginosa pathogenicity, Repressor Proteins genetics, Repressor Proteins metabolism, Bacterial Proteins genetics, Pseudomonas aeruginosa physiology
- Abstract
It is generally believed that the Pseudomonas aeruginosa biofilm matrix itself acts as a molecular sieve or sink that contributes to significant levels of drug resistance, but it is becoming more apparent that multidrug efflux pumps induced during biofilm growth significantly enhance resistance levels. We present here a novel transcriptional regulator, PA3898, which controls biofilm formation and multidrug efflux pumps in P. aeruginosa A mutant of this regulator significantly reduced the ability of P. aeruginosa to produce biofilm in vitro and affected its in vivo fitness and pathogenesis in Drosophila melanogaster and BALB/c mouse lung infection models. Transcriptome analysis revealed that PA3898 modulates essential virulence genes/pathways, including multidrug efflux pumps and phenazine biosynthesis. Chromatin immunoprecipitation sequencing (ChIP-seq) identified its DNA binding sequences and confirmed that PA3898 directly interacts with promoter regions of four genes/operons, two of which are mexAB-oprM and phz2 Coimmunoprecipitation revealed a regulatory partner of PA3898 as PA2100, and both are required for binding to DNA in electrophoretic mobility shift assays. PA3898 and PA2100 were given the names MdrR1 and MdrR2, respectively, as novel repressors of the mexAB-oprM multidrug efflux operon and activators for another multidrug efflux pump, EmrAB. The interaction between MdrR1 and MdrR2 at the promoter regions of their regulons was further characterized via localized surface plasmon resonance and DNA footprinting. These regulators directly repress the mexAB-oprM operon, independent of its well-established MexR regulator. Mutants of mdrR1 and mdrR2 caused increased resistance to multiple antibiotics in P. aeruginosa , validating the significance of these newly discovered regulators., (Copyright © 2018 American Society for Microbiology.) more...
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- 2018
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34. Assessment of Bacterial Accumulation and Environmental Factors in Sentinel Oysters and Estuarine Water Quality from the Phang Nga Estuary Area in Thailand.
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Jeamsripong S, Chuanchuen R, and Atwill ER
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- Animals, Estuaries, Shellfish analysis, Shellfish microbiology, Temperature, Thailand, Water Quality, Bacteria isolation & purification, Food Contamination analysis, Metals, Heavy analysis, Ostreidae chemistry, Ostreidae microbiology, Water Pollutants analysis
- Abstract
This study characterized microbiological and chemical contamination of oyster meat and estuarine water in Phang Nga, Thailand. Pooled oyster meats ( n = 144), estuarine waters ( n = 96) and environmental parameters were collected from March, 2016 to February, 2017, and assessed for levels of total coliforms (TC), fecal coliforms (FC), Escherichia coli (EC), and Vibrio parahaemolyticus (VP), presence of Salmonella and Shigella and levels of heavy metals (Mn, Pb and Cd). The prevalence of TC, FC and EC were in 99.3%, 94.4% and 93.1% of oyster meat and 94.8%, 79.2%, and 78.1% of water, respectively. The average VP levels was 8.5 × 10⁷ most probable number (MPN)/g oyster. Prevalence of Shigella and Salmonella in the pooled oysters were 7.6% and 30.6%, respectively. The dominant Salmonella serovars were Paratyphi B followed by Seremban, and Kentucky. In contrast, the prevalence of Shigella were 27.1%, but Salmonella was not detected in estuarine water. Factors statistically associated with EC accumulation in oyster were level of FC, 7-day average precipitation, temperature, relative humidity, and presence of Salmonella in the sample. The optimal cutoff value of EC to predict Salmonella in oyster was 420 MPN/g. Results indicate this area has relatively safe levels of heavy metals, whereas bacterial contamination was very high for oysters. more...
- Published
- 2018
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35. Novel dual regulators of Pseudomonas aeruginosa essential for productive biofilms and virulence.
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Heacock-Kang Y, Zarzycki-Siek J, Sun Z, Poonsuk K, Bluhm AP, Cabanas D, Fogen D, McMillan IA, Chuanchuen R, and Hoang TT
- Subjects
- Animals, Bacterial Proteins genetics, Bacterial Proteins metabolism, Disease Models, Animal, Drosophila melanogaster, Gene Expression Profiling, Humans, Lung Diseases microbiology, Male, Mice, Mice, Inbred BALB C, Pseudomonas aeruginosa genetics, Transcription Factors genetics, Virulence, Biofilms growth & development, Pseudomonas Infections microbiology, Pseudomonas aeruginosa pathogenicity, Pseudomonas aeruginosa physiology, Transcription Factors metabolism
- Abstract
Gene regulation network in Pseudomonas aeruginosa is complex. With a relatively large genome (6.2 Mb), there is a significant portion of genes that are proven or predicted to be transcriptional regulators. Many of these regulators have been shown to play important roles in biofilm formation and maintenance. In this study, we present a novel transcriptional regulator, PA1226, which modulates biofilm formation and virulence in P. aeruginosa. Mutation in the gene encoding this regulator abolished the ability of P. aeruginosa to produce biofilms in vitro, without any effect on the planktonic growth. This regulator is also essential for the in vivo fitness and pathogenesis in both Drosophila melanogaster and BALB/c mouse lung infection models. Transcriptome analysis revealed that PA1226 regulates many essential virulence genes/pathways, including those involved in alginate, pili, and LPS biosynthesis. Genes/operons directly regulated by PA1226 and potential binding sequences were identified via ChIP-seq. Attempts to confirm the binding sequences by electrophoretic mobility shift assay led to the discovery of a co-regulator, PA1413, via co-immunoprecipitation assay. PA1226 and PA1413 were shown to bind collaboratively to the promoter regions of their regulons. A model is proposed, summarizing our finding on this novel dual-regulation system., (© 2018 John Wiley & Sons Ltd.) more...
- Published
- 2018
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36. Present and Future Surveillance of Antimicrobial Resistance in Animals: Principles and Practices.
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Simjee S, McDermott P, Trott DJ, and Chuanchuen R
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- Animals, Anti-Bacterial Agents pharmacology, Bacteria drug effects, Bacteria genetics, Bacteria pathogenicity, Bacterial Infections epidemiology, Bacterial Infections microbiology, Bacterial Infections veterinary, Genes, Bacterial, Humans, Livestock, Metagenomics methods, Microbial Sensitivity Tests, Molecular Diagnostic Techniques, Zoonoses epidemiology, Zoonoses microbiology, Drug Resistance, Bacterial drug effects, Drug Resistance, Bacterial genetics, Epidemiological Monitoring veterinary, Sentinel Surveillance veterinary
- Abstract
There is broad consensus internationally that surveillance of the levels of antimicrobial resistance (AMR) occurring in various systems underpins strategies to address the issue. The key reasons for surveillance of resistance are to determine (i) the size of the problem, (ii) whether resistance is increasing, (iii) whether previously unknown types of resistance are emerging, (iv) whether a particular type of resistance is spreading, and (v) whether a particular type of resistance is associated with a particular outbreak. The implications of acquiring and utilizing this information need to be considered in the design of a surveillance system. AMR surveillance provides a foundation for assessing the burden of AMR and for providing the necessary evidence for developing efficient and effective control and prevention strategies. The codevelopment of AMR surveillance programs in humans and animals is essential, but there remain several key elements that make data comparisons between AMR monitoring programs, and between regions, difficult. Currently, AMR surveillance relies on uncomplicated in vitro antimicrobial susceptibility methods. However, the lack of harmonization across programs and the limitation of genetic information of AMR remain the major drawbacks of these phenotypic methods. The future of AMR surveillance is moving toward genotypic detection, and molecular analysis methods are expected to yield a wealth of information. However, the expectation that these molecular techniques will surpass phenotypic susceptibility testing in routine diagnosis and monitoring of AMR remains a distant reality, and phenotypic testing remains necessary in the detection of emerging resistant bacteria, new resistance mechanisms, and trends of AMR. more...
- Published
- 2018
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37. Phenotypic and genotypic antimicrobial resistance and virulence genes of Salmonella enterica isolated from pet dogs and cats.
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Srisanga S, Angkititrakul S, Sringam P, Le Ho PT, T Vo AT, and Chuanchuen R
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- Animals, Anti-Bacterial Agents therapeutic use, Cat Diseases drug therapy, Cat Diseases microbiology, Cats, Dog Diseases drug therapy, Dog Diseases microbiology, Dogs, Drug Resistance, Bacterial genetics, Integrons genetics, Microbial Sensitivity Tests veterinary, Polymerase Chain Reaction veterinary, Salmonella Infections, Animal drug therapy, Salmonella enterica drug effects, Salmonella enterica pathogenicity, Serotyping veterinary, Salmonella Infections, Animal microbiology, Salmonella enterica genetics, Virulence Factors genetics
- Abstract
Salmonella enterica isolates (n = 122), including 32 serotypes from 113 dogs and 9 cats, were obtained from household dogs (n = 250) and cats (n = 50) during 2012-2015. The isolates were characterized by serotyping, antimicrobial resistance phenotyping and genotyping, and virulence gene screening. Serovars Weltevreden (15.6%) and Typhimurium (13.9%) were the most common. The majority (43%) of the isolates were multidrug resistant. The dog isolates (12.3%) harbored class 1 integrons, of which the dfrA12 - aadA2 cassette was most frequent (66.7%). The only class integron in serovar Albany was located on a conjugative plasmid. Two ESBL-producing isolates ( i.e ., a serovar Krefeld and a serovar Enteritridis) carried bla
TEM and blaCTX-M , and the blaTEM gene in both was horizontally transferred. Of the plasmid-mediated quinolone resistance genes tested, only qnrS (4.9%) was detected. Most Salmonella isolates harbored invA (100%), prgH (91.8%), and sipB (91%). Positive associations between resistance and virulence genes were observed for blaPSE-1 / orgA , cmlA / span , tolC , and sul1 / tolC ( p < 0.05). The results suggest that companion dogs and cats are potential sources of S. enterica strains that carry resistance and virulence genes and that antimicrobial use in companion animals may select for the examined Salmonella virulence factors. more...- Published
- 2017
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38. Prevalence and antimicrobial resistance in Salmonella enterica isolated from broiler chickens, pigs and meat products in Thailand-Cambodia border provinces.
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Trongjit S, Angkititrakul S, Tuttle RE, Poungseree J, Padungtod P, and Chuanchuen R
- Subjects
- Ampicillin pharmacology, Animals, Bacterial Proteins genetics, Cambodia epidemiology, Chickens, DNA, Bacterial genetics, Drug Resistance, Multiple, Bacterial, Food Microbiology, Poultry Diseases epidemiology, Poultry Diseases microbiology, Prevalence, Salmonella enterica drug effects, Salmonella enterica genetics, Sulfamethoxazole pharmacology, Swine, Swine Diseases epidemiology, Swine Diseases microbiology, Thailand epidemiology, Anti-Infective Agents pharmacology, Meat Products microbiology, Salmonella Infections, Animal epidemiology, Salmonella Infections, Animal microbiology, Salmonella enterica isolation & purification
- Abstract
This study aimed to examine the prevalence and antimicrobial resistance (AMR) of Salmonella isolates from broiler chickens, pigs and their associated meat products in the Thailand-Cambodia border provinces. A total of 941 samples were collected from pigs and broiler chickens at slaughter houses and from carcasses at local fresh markets in Sa Kaeo, Thailand (n = 554) and Banteay Meanchey, Cambodia (n = 387) in 2014 and 2015. From these samples, 345 Salmonella isolates were collected from Sa Keao (n = 145; 23%) and Banteay Meanchey (n = 200; 47%) and assayed for antimicrobial susceptibility, class 1 integrons and extended-spectrum β-lactamase (ESBL) genes. Serovars Typhimurium (29%) and Rissen (29%) were the most common serotypes found in Thai and Cambodian isolates, respectively. Multidrug resistance was detected in 34% and 52% of isolates from Sa Keao and Banteay Meanchey, respectively. The majority of the Thai isolates were resistant to ampicillin (72.4%), whereas most Cambodian isolates were resistant to sulfamethoxazole (71%). Eleven isolates from Sa Keao and 44 from Banteay Meanchey carried class 1 integrons comprising resistance gene cassettes. The most common gene cassette array was dfrA12-aadA2 (61.1%). Six isolates were ESBL producers. The β-lactamase genes found included bla
TEM-1 , blaCTX-M-55 and blaCMY-2 . Some of these class 1 integrons and ESBL genes were located on conjugative plasmid. In conclusion, multidrug-resistant Salmonella are common in pigs, chickens and their products in the Thailand-Cambodia border provinces. Our findings indicate that class 1 integrons play a role in spread of AMR in the strains in this study., (© 2017 The Societies and John Wiley & Sons Australia, Ltd.) more...- Published
- 2017
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39. High prevalence and molecular characteristics of multidrug-resistant Salmonella in pigs, pork and humans in Thailand and Laos provinces.
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Sinwat N, Angkittitrakul S, Coulson KF, Pilapil FMIR, Meunsene D, and Chuanchuen R
- Subjects
- Animals, Anti-Bacterial Agents pharmacology, Bacterial Proteins genetics, Bacterial Proteins metabolism, Food Contamination analysis, Food Contamination statistics & numerical data, Humans, Integrons, Laos epidemiology, Prevalence, Salmonella classification, Salmonella drug effects, Salmonella genetics, Salmonella Infections epidemiology, Salmonella Infections, Animal epidemiology, Swine, Swine Diseases epidemiology, Thailand epidemiology, beta-Lactamases genetics, beta-Lactamases metabolism, Drug Resistance, Multiple, Bacterial, Meat microbiology, Salmonella isolation & purification, Salmonella Infections microbiology, Salmonella Infections, Animal microbiology, Swine Diseases microbiology
- Abstract
This study aimed to examine occurrence and antimicrobial resistance characteristics of Salmonella from pigs, pork and humans in Thailand and Laos provinces. The samples were collected from pigs, carcasses and workers in slaughterhouses, retail pork and butchers in fresh markets and patients in hospitals in Thailand (n=729) and Laos (n=458). A total of 295 of 729 samples (34.6 %) collected in Thailand and 253 of 458 (47.4 %) samples collected in Laos were positive for Salmonella. A total of 548 Salmonella isolates from Thailand (n=295) and Laos (n=253) were further analysed. Serovar Typhimurium was the most common serotype in Thai (34 %) and Laos (20.6 %) samples. Approximately 2.4 % of Thai isolates produced extended-spectrum β-lactamase (ESBL). All the ESBL producers possessed blaCTX-M-14, some of which were horizontally transferred. Class 1 integrons were common in Thai (31.9 %) and Laos (39.1 %) isolates, but none were associated with SGI1. The resistance cassette dfrA12-aadA2 was the most common, while the least common was aadA2-linG (n=1). The dfrA12-aadA2 gene cassette in five isolates and aadA2-linG were located on conjugative plasmid. Three pork isolates were fluoroquinolone resistant and carried an amino acid substitute, Ser-83-Tyr, in GyrA. The qnrS gene was found in 7.1 and 5.5 % of the Thai and Laos isolates, respectively, while qnrB was carried in another Laos isolate (1.9 %). All ESBL producers carried qnrS. In conclusion, multidrug-resistant Salmonella was common in pigs, pork and human samples in this region. The bacteria carried mobile genetic elements and resistance genes on conjugative plasmids that could be readily transferred to other bacterial species. more...
- Published
- 2016
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40. Occurrence and molecular characteristics of antimicrobial resistance of Escherichia coli from broilers, pigs and meat products in Thailand and Cambodia provinces.
- Author
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Trongjit S, Angkittitrakul S, and Chuanchuen R
- Subjects
- Animals, Anti-Bacterial Agents pharmacology, Cambodia epidemiology, Chickens, Conjugation, Genetic, Cross-Sectional Studies, DNA, Bacterial, Genes, Bacterial, Humans, Microbial Sensitivity Tests, Phenotype, Prevalence, Public Health Surveillance, Sequence Analysis, DNA, Swine, Thailand epidemiology, beta-Lactamases genetics, Drug Resistance, Bacterial, Escherichia coli drug effects, Escherichia coli genetics, Escherichia coli Infections epidemiology, Escherichia coli Infections microbiology, Food Microbiology, Meat Products microbiology
- Abstract
Nine hundred and forty-one samples were collected in Sa Keao, Thailand (n = 554) and Banteay Meanchey, Cambodia (n = 387) from July 2014 to January 2015. A total of 667 Escherichia coli isolates (381 isolates from Sa Keao and 286 isolates from Banteay Meanchey) were obtained and examined for antimicrobial susceptibility, class 1 integrons, ESBL genes and horizontal transfer of resistance determinants. Prevalence of E. coli in pig and broiler carcass samples from slaughterhouses and fresh markets was 36-85% in Sa Keao and 11-69% in Banteay Meanchey. The majority of these isolates were multidrug resistant (75.3%). Class 1 integrons were common in both Thai (47%) and Cambodian (62%) isolates, of which four resistance gene cassette arrays including aadA1, dfrA1-aadA1, dfrA12-aadA2 and aadA2-linF were identified. Class 1 integrons in two broiler isolates from Sa Keao (dfrA12-aadA2) and one broiler isolate from Banteay Meanchey (dfrA1-aadA1) were horizontally transferable. Sixteen isolates were confirmed to be ESBL-producing strains with ESBL gene blaCTX-M-15 , broad spectrum β-lactamase gene blaTEM-1 and the AmpC gene blaCMY-2 being detected. The blaTEM-1 gene was most prevalent and located on a conjugative plasmid., (© 2016 The Societies and John Wiley & Sons Australia, Ltd.) more...
- Published
- 2016
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41. Distribution and expression of the Ade multidrug efflux systems in Acinetobacter baumannii clinical isolates.
- Author
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Pagdepanichkit S, Tribuddharat C, and Chuanchuen R
- Subjects
- Acinetobacter baumannii drug effects, Acinetobacter baumannii isolation & purification, Anti-Bacterial Agents pharmacology, Bacterial Proteins genetics, Bacterial Proteins metabolism, Humans, Membrane Transport Proteins genetics, Membrane Transport Proteins metabolism, Acinetobacter baumannii metabolism, Drug Resistance, Multiple, Bacterial genetics
- Abstract
One hundred Acinetobacter baumannii clinical isolates were examined for inhibitory effect of reserpine and carbonyl cyanide m-chlorophenylhydrazone (CCCP) on the antimicrobial susceptibility and expression of 4 resistant-nodulation-cell division (RND)-type multidrug efflux systems, including AdeABC, AdeDE, AdeIJK, and AdeFGH, using RT-PCR. Ten A. baumannii isolates expressing AdeABC, AdeIJK, or AdeFGH were randomly selected for determination of transcription level and regulatory mutations. While all the isolates were resistant to multiple drugs, the reserpine and CCCP experiment showed that the multidrug resistance phenotype in most A. baumannii isolates was associated with efflux pumps. Most isolates expressed at least one of the RND-type efflux pumps tested (97%). AdeIJK expression was most common (97%), but none of the isolates produced AdeDE. Fifty-two percent of the A. baumannii isolates simultaneously produced up to 3 RND-type efflux systems (i.e., AdeABC, AdeFGH, and AdeIJK). No good correlation between the expression of RND-type efflux pumps and the type of antimicrobial resistance was observed. Overexpression of AdeABC, AdeIJK, and AdeFGH was not always related to the presence of mutations in their corresponding regulatory genes. This study highlights (i) the universal presence of the RND-type efflux pumps with variable levels of expression level among the A. baumannii in this collection and (ii) the complexity of their regulation of expression. more...
- Published
- 2016
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42. Characterization of Antimicrobial Resistance in Salmonella enterica Isolated from Pork, Chicken Meat, and Humans in Northeastern Thailand.
- Author
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Sinwat N, Angkittitrakul S, and Chuanchuen R
- Subjects
- Animals, Carbon-Oxygen Lyases analysis, Chickens, DEAD-box RNA Helicases analysis, Fimbriae Proteins analysis, Genotype, Humans, Phenotype, Plasmids analysis, Plasmids genetics, Poultry microbiology, Proto-Oncogene Proteins analysis, Salmonella enterica genetics, Salmonella enterica immunology, Salmonella enterica isolation & purification, Swine, Thailand, Virulence Factors genetics, Anti-Infective Agents pharmacology, Drug Resistance, Multiple, Bacterial genetics, Food Microbiology, Meat microbiology, Salmonella enterica drug effects
- Abstract
A total of 221 Salmonella enterica from raw pork (n=64), raw chicken (n=80), and humans (n=77) were characterized for antimicrobial resistance phenotypes and genotypes and virulence plasmid-associated genes. Most Salmonella isolates (95.9%) were multidrug resistant and exhibited high resistance to sulfamethoxazole (96.4%), streptomycin (93.2%), spectinomycin (76.5%), tetracycline (73.3%), ampicillin (70.1%), and trimethoprim (60.2%). Forty-one percent of all isolates were intI1-positive, of which 60% carried class 1 integrons with variable region ranging in size from 0.2 to 2.0 kb. Six integron profiles (IP-I to IP-VI) were defined. The dfrA12-aadA2 cassette was most prevalent (66.7%). Class 1 integrons with the dfrA12-aadA2 cassette in five pork isolates could be horizontally transferred. Three pork isolates carried Salmonella genomic island 1 (SGI1), of which a serovar Anatum harbored SGI1 gene cluster located between thdF and int2. Two single-point mutations (i.e., G-259-T and C-248-T) in gyrA leading to Asp-87-Tyr and Ser-83-Phe substitutions in GyrA, respectively, were detected. Of all plasmid-mediated quinolone resistance genes tested, only qnrS (4.1%) and qnrB (1.8%) were found. The virulence plasmid-associated genes including spvC, pefA, and rck were identified in 8.1%, 1.8%, and 1.4% of all Salmonella isolates, respectively. more...
- Published
- 2015
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43. Simultaneous overexpression of multidrug efflux pumps in Pseudomonas aeruginosa non-cystic fibrosis clinical isolates.
- Author
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Poonsuk K, Tribuddharat C, and Chuanchuen R
- Subjects
- Anti-Bacterial Agents pharmacology, Bacterial Outer Membrane Proteins genetics, Drug Resistance, Multiple genetics, Membrane Transport Proteins genetics, Mutation, Pseudomonas Infections microbiology, Pseudomonas aeruginosa drug effects, Pseudomonas aeruginosa genetics, RNA, Bacterial genetics, RNA, Bacterial isolation & purification, Real-Time Polymerase Chain Reaction, Sequence Analysis, DNA, Bacterial Outer Membrane Proteins metabolism, Gene Expression Regulation, Bacterial, Genes, Regulator genetics, Membrane Transport Proteins metabolism, Pseudomonas aeruginosa metabolism
- Abstract
The purpose of this study was to examine expression and regulation of 6 multidrug efflux systems, including MexAB-OprM, MexCD-OprJ, MexEF-OprN, MexXY, MexJK, and MexVW, in 13 non-cystic fibrosis (CF) clinical isolates of Pseudomonas aeruginosa. These isolates displayed a high level of resistance to many clinically important antibiotics. Some isolates simultaneously overexpressed up to 4 different Mex systems, as determined by quantitative real-time reverse transcription PCR. None of the isolates overexpressed MexCD-OprJ, and only 1 isolate overproduced MexJK. All the isolates overexpressed MexXY, while overexpression of MexEF-OprN and MexVW was common. DNA sequencing analysis of regulatory genes showed that no clear correlation could be established among (i) the presence of mutations, (ii) the type of mutations, (iii) the expression level of the Mex systems, and (iv) resistance to antibiotic substrates. The results suggest that the concomitant overexpression of some Mex systems may superimpose their antimicrobial drug efflux capabilities, contributing to the multidrug resistance phenotype in the P. aeruginosa non-CF clinical isolates. The existence of uncharacterized regulators for the Mex systems was signified. more...
- Published
- 2014
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44. Aminoglycoside resistance mechanisms in Pseudomonas aeruginosa isolates from non-cystic fibrosis patients in Thailand.
- Author
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Poonsuk K, Tribuddharat C, and Chuanchuen R
- Subjects
- Bacterial Proteins genetics, Enzymes genetics, Gene Expression Regulation, Bacterial, Humans, Microbial Sensitivity Tests, Mutation, Pseudomonas aeruginosa genetics, Thailand, Aminoglycosides pharmacology, Anti-Bacterial Agents pharmacology, Drug Resistance, Bacterial genetics, Pseudomonas aeruginosa drug effects, Pseudomonas aeruginosa enzymology
- Abstract
This study aimed to examine aminoglycosides (AMGs) resistance mechanisms, including the AMG-modifying enzyme genes, mexXY, rplY, nuoG, and galU, in the Pseudomonas aeruginosa non-cystic fibrosis (CF) isolates in Thailand. One hundred P. aeruginosa isolates from non-CF patients were examined for susceptibility to AMGs and for the presence of 10 AMG-modifying enzyme genes. Thirty randomly selected isolates were tested for transcription of mexXY and nuoG and mutations in rplY and galU. All the P. aeruginosa isolates exhibited simultaneous resistance to at least 4 AMGs. High resistance rates to amikacin (92%), gentamicin (95%), streptomycin (99%), and tobramycin (96%) were observed, and all isolates were resistant to kanamycin, neomycin, and spectinomycin. Nine AMG-modifying enzyme genes were detected, including aadA1 (84%), aadB (84%), aadA2 (67%), ant(2″)-Ia (72%), strA-strB (70%), aph(3')-IIb (57%), aac(3')-Ia (40%), and aac(6')-IIa (27%). None of the isolates harbored aac(6')-IIb. Of 30 isolates tested, all but 1 isolate expressed MexXY. Two isolates did not express nuoG. Six isolates carried an amino acid change in RplY, but none of the isolates harbored mutation in galU. The results indicated that the AMG-modifying enzyme genes were widespread among the P. aeruginosa non-CF isolates. The MexXY efflux pump and inactivation for rplY played a role in AMG resistance but disruption of nuoG or galU did not. more...
- Published
- 2013
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45. Contribution of the MexXY multidrug efflux pump and other chromosomal mechanisms on aminoglycoside resistance in Pseudomonas aeruginosa isolates from canine and feline infections.
- Author
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Poonsuk K and Chuanchuen R
- Subjects
- Animals, Cat Diseases drug therapy, Cats, DNA Primers genetics, Dog Diseases drug therapy, Dogs, Microbial Sensitivity Tests, Real-Time Polymerase Chain Reaction veterinary, Reverse Transcriptase Polymerase Chain Reaction veterinary, Aminoglycosides pharmacology, Bacterial Proteins metabolism, Cat Diseases microbiology, Dog Diseases microbiology, Drug Resistance, Bacterial genetics, Pseudomonas Infections veterinary, Pseudomonas aeruginosa
- Abstract
As study of multidrug efflux pumps is a crucial step for development of efflux pump inhibitors for treatment of Pseudomonas aeruginosa infection, the objective of this study was to examine the contribution of the MexXY multidrug efflux systems and other chromosomal mechanisms in aminoglycoside (AMG) resistance in P. aeruginosa isolated from dogs and cats. Thirteen Pseudomonas aeruginosa isolates from canine and feline infections were examined for contribution of the MexXY multidrug efflux pump and four other chromosomally-encoded genes including PA5471, galU, nuoG and rplY to AMG resistance. All the isolates were resistant to multiple AMGs and expressed mexXY. Deletion of mexXY caused 2- to 16-fold reduction in AMG MICs. Overproduction of MexXY did not fully account for the observed AMG resistance. No good correlations were detected between MexXY transcription level and AMG MICs. While no mutations were found in mexZ, PA5471 expression varied and its impact on MexXY expression and AMG resistance is diverse. No mutations were found in galU. Only two isolates carried a single base change G-367-T in rplY. Complete transcription of nuoG was detected in all the isolates. In conclusion, the MexXY multidrug efflux pump plays a role in AMG resistance in the dog and cat P. aeruginosa isolates, while disruption of nuoG, rplY and galU did not have a significant impact. These results indicate the existence of uncharacterized AMG-resistance mechanisms. more...
- Published
- 2012
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46. Antimicrobial resistance, virulence, and phylogenetic characteristics of Escherichia coli isolates from clinically healthy swine.
- Author
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Lay KK, Koowattananukul C, Chansong N, and Chuanchuen R
- Subjects
- Animals, DNA Gyrase genetics, DNA Topoisomerase IV genetics, DNA, Bacterial chemistry, DNA, Bacterial genetics, Escherichia coli classification, Escherichia coli drug effects, Escherichia coli pathogenicity, Escherichia coli Infections microbiology, Gene Transfer, Horizontal, Genotype, Integrons genetics, Microbial Sensitivity Tests, Mutation, Phenotype, Phylogeny, Sequence Analysis, DNA, Swine, Thailand, Virulence genetics, Virulence Factors genetics, Anti-Infective Agents pharmacology, Bacterial Proteins genetics, Drug Resistance, Multiple, Bacterial genetics, Escherichia coli genetics, Escherichia coli Infections veterinary, Swine Diseases microbiology
- Abstract
A total of 344 commensal Escherichia coli isolates from clinically healthy pigs were examined for antimicrobial resistance phenotypes, class 1 integrons, resistance genes, virulence gene profile, and phylogenetic groups. The majority of E. coli isolates were resistant to tetracycline (96.2%) and ampicillin (91.6%). Up to 98% were multidrug resistant. Seventy-three percent of the isolates carried class 1 integrons. Inserted-gene cassette arrays in variable regions included incomplete sat, aadA22, aadA1, dfrA12-aadA2, and sat-psp-aadA2, of which the aadA2 gene cassette was most prevalent (42.9%). Horizontal transfer was detected in eight E. coli isolates carrying class 1 integrons with dfrA12-aadA2 gene cassette array. Sixteen resistance genes were identified among the E. coli isolates with corresponding resistance phenotype. Ten virulence genes (including elt, estA, estB, astA, faeG, fasA, fedA, eaeA, paa, and sepA) were detected, of which fasA was most commonly found (98.3%). Most of the E. coli isolates belonged to phylogenetic group B1. Significantly positive associations were observed between some virulence genes and some resistance phenotypes and genotypes (p < 0.05). The results support a finding that commensal E. coli have a role as reservoirs for antimicrobial resistance-encoding genes and virulence determinants. more...
- Published
- 2012
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47. Global transcriptional responses to triclosan exposure in Pseudomonas aeruginosa.
- Author
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Chuanchuen R and Schweizer HP
- Subjects
- Acyl Carrier Protein genetics, Acyl Carrier Protein metabolism, Bacterial Proteins genetics, Bacterial Proteins metabolism, Genes, Bacterial, Homeostasis, Iron metabolism, Microbial Sensitivity Tests, Oligonucleotide Array Sequence Analysis, Pseudomonas aeruginosa genetics, Pseudomonas aeruginosa metabolism, Quorum Sensing, RNA, Bacterial genetics, Real-Time Polymerase Chain Reaction, Anti-Infective Agents, Local pharmacology, Gene Expression Regulation, Bacterial, Pseudomonas aeruginosa drug effects, Transcription, Genetic, Triclosan pharmacology
- Abstract
Global gene transcription was assessed by microarray experiments following treatment of a triclosan-susceptible Δ(mexAB-oprM) Pseudomonas aeruginosa strain with subinhibitory concentrations of triclosan. Expression patterns of selected genes were verified by quantitative real-time PCR analysis. The results showed that triclosan exposure had a profound effect on gene expression, affecting 44% of the genes present on the Affymetrix GeneChip(®), with 28% of genes being significantly upregulated and 16% being significantly downregulated in triclosan-treated cells. Genes encoding membrane proteins, transporters of small molecules, aspects of amino acid metabolism, and transcriptional regulators were significantly over-represented among the more strongly upregulated or downregulated genes in triclosan-treated cells. Quorum sensing-regulated genes were among the most strongly downregulated genes, presumably because of decreased acyl-acyl carrier protein pools and the resulting reduced acyl-homoserine lactone molecule synthesis. Surprisingly, iron homeostasis was completed perturbed in triclosan-exposed cells, with iron acquisition systems being strongly downregulated and iron storage systems significantly upregulated, thus mimicking conditions of excess iron. The profound perturbations of cellular metabolism via specific and global mechanisms may explain why triclosan is such a potent antimicrobial in susceptible bacteria., (Copyright © 2012 Elsevier B.V. and the International Society of Chemotherapy. All rights reserved.) more...
- Published
- 2012
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48. Class 1 integrons in Aeromonas hydrophila isolates from farmed Nile tilapia (Oreochromis nilotica).
- Author
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Lukkana M, Wongtavatchai J, and Chuanchuen R
- Subjects
- Animals, Anti-Bacterial Agents therapeutic use, Aquaculture, Conjugation, Genetic genetics, DNA Gyrase genetics, DNA Topoisomerase IV genetics, DNA, Bacterial chemistry, DNA, Bacterial genetics, Drug Resistance, Multiple, Bacterial genetics, Fish Diseases drug therapy, Fluoroquinolones therapeutic use, Gram-Negative Bacterial Infections drug therapy, Gram-Negative Bacterial Infections microbiology, Integrases genetics, Microbial Sensitivity Tests veterinary, Polymerase Chain Reaction veterinary, Sequence Analysis, DNA, Aeromonas hydrophila genetics, Anti-Bacterial Agents pharmacology, Cichlids, Fish Diseases microbiology, Fluoroquinolones pharmacology, Gram-Negative Bacterial Infections veterinary, Integrons
- Abstract
The aim of this study was to determine antimicrobial resistance of Aeromonas hydrophila isolated from farmed Nile Tilapia. A total of 50 A. hydrophila isolates from clinical cases were screened for the presence of class 1, 2 and 3 integrons and all the strains resistant to enrofloxacin and/or ciprofloxacin (n=19) examined for mutation in the quinolone resistance-determining regions (QRDRs) of gyrA and parC. The intI1 gene was detected in 23 A. hydrophila strains (46%) but no intl2 and intl3 were detected. Among these, 14 isolates (60.8%) carried gene cassettes inserted in variable regions i.e., partial aadA2, aadA2, dfrA1-orfC and dfrA12-aadA2, of which the most common gene cassette array was dfrA12-aadA2 (26.09%). Conjugal transfer of class 1 integrons with resistance gene array was detected. All the A. hydrophila strains resistant to enrofloxacin and/or ciprofloxacin possessed mutations in the QRDRs of gyrA and parC. Only a Ser-83-Ile substitution was identified in GyrA and only a Ser-80-Ile amino change was found in ParC. The data confirms that A. hydrophila from farm-raised Nile Telapia serve as a reservoir for antimicrobial resistance determinants. more...
- Published
- 2012
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49. Class 1 integrons in Pseudomonas aeruginosa and Acinetobacter baumannii isolated from clinical isolates.
- Author
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Poonsuk K, Tribuddharat C, and Chuanchuen R
- Subjects
- Acinetobacter baumannii drug effects, Acinetobacter baumannii isolation & purification, Cross Infection microbiology, Drug Resistance, Multiple, Bacterial genetics, Humans, Microbial Sensitivity Tests, Polymerase Chain Reaction, Pseudomonas aeruginosa drug effects, Pseudomonas aeruginosa isolation & purification, Thailand, Acinetobacter baumannii genetics, DNA, Bacterial genetics, Integrons genetics, Pseudomonas aeruginosa genetics
- Abstract
Resistance to various antimicrobial agents is an increasing problem in Pseudomonas aeruginosa and Acinetobacter baumannii infections. In this study, the roles of integrons were examined in 101 P. aeruginosa isolates and 176 A. baumannii isolates from patients. The frequencies and characteristics of class 1, 2 and 3 integrons were investigated and the horizontal transfer of integrons was assessed. Among these isolates, class 1 integrons with a resistance gene cassette were detected in 69.3% of P. aeruginosa and 31.8% of A. baumannii isolates, but class 2 and 3 integrons were not found. Five novel gene cassette arrays were identified in P. aeruginosa: aacA7-cmlA, aadB-blaOXA,-o-aadA1, aadB-arr-2-cmlA-blaOXA,-o-aadA1, aadB-cmlA-aadA1 and aadB-cmlA-blaOXA-10-aadA15. The integrons found in A. baumannii isolates in this study were previously reported. Horizontal transfer of some class 1 integrons was detected in both P. aeruginosa (2/70) and A. baumannii (5/57). These data confirm the high prevalence of class 1 integrons with a variety of gene cassette combinations among multidrug-resistant P. aeruginosa and A. baumannii clinical isolates. more...
- Published
- 2012
50. Widespread presence of dfrA12 and its association with dfrA12-aadA2 cassette in Salmonella enterica isolates from swine.
- Author
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Padungtod P, Tribuddharat C, and Chuanchuen R
- Subjects
- Animals, DNA, Bacterial genetics, Drug Resistance, Multiple, Bacterial, Gene Expression Regulation, Bacterial, Microbial Sensitivity Tests, Polymerase Chain Reaction, Prevalence, Salmonella enterica isolation & purification, Thailand, Anti-Bacterial Agents pharmacology, Integrons genetics, Salmonella enterica drug effects, Salmonella enterica genetics, Swine microbiology, Trimethoprim pharmacology
- Abstract
One hundred and eighty-nine Salmonella isolates from swine were tested for susceptibility to nine antimicrobial agents, presence of dfrA12 and class 1 integrons containing dfrA12-orfF-aadA2 cassette. All isolates were multidrug resistant and exhibited highest resistance prevalence to trimethoprim (93%). Most isolates (89%) were intll-positive and 107 isolates (57%) carried dfrA12, all of which were resistant to trimethoprim. Forty-eight dfrA12-harboring strains (45%) were intl1-positive together with dfrA12-aadA2 gene cassette. Fifteen isolates contained dfrA12 but not intl1 and dfrA12-aadA2 cassette. The results indicated a wide distribution of dfrA12 and its role in dissemination of trimethoprim resistance among Salmonella isolates from fattening pigs. more...
- Published
- 2011
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