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Achromobacter marplatensis strain YKS2 isolated from the yak rumen has the feature of producing cellulose. This study aims to analyze the genome and safety of strain YKS2 in vivo, considering its future research and application prospects. The genome of strain YKS2 was sequenced and used for genomic in silico studies. The administration of strain YKS2 in three doses was carried out on mice for 3 days of oral and 7 days of clinical observation tests. The BW, FI, organ indices, gut microbiota, and histological appearances of organs and intestines, along with hematological parameters and serum biochemistry, were measured in mice. The chromosome size of strain YKS2 was 6,588,568 bp, with a GC content of 65.27%. The 6058 coding sequences of strain YKS2 without plasmid were predicted and annotated and have multiple functions. The mice in all groups were alive, with good mental states and functional activities. Compared with the control group, there was no significant difference in the three dose groups on BW, FI, hematological parameters (WBC, LYM, etc.), and serum biochemistry (ALB, ALT, etc.). No abnormalities were observed in the main visceral organs, intestinal tissue, and V/C value in groups. However, the IEL number of duodenum and gut microbiota diversity (Shannon's index) in the high-dose group was significantly higher than in the control group (p < 0.05). Besides, the low dose of strain YKS2 also significantly affected the bacterial abundance of Firmicutes, Actinobacteria, and desulphurizing Bacteroidetes at the phylum level. There was no significant effect at genus levels in groups. In conclusion, the study revealed the genome and potential functional genes of strain YKS2, which is beneficial to understanding the features of the A. marplatensis strain and proved strain YKS2 to be without acute toxicity to mice. However, a long-term feeding toxicity experiment in vivo should be performed to further ensure its potential application value strain in the animal industry., (© 2023. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

The heterotrophic nitrification aerobic denitrification bacteria (HNDS) can perform nitrification and denitrification at the same time. Two HNDS strains, Achromobacter sp. HNDS-1 and Enterobacter sp. HNDS-6 which exhibited an amazing ability to solution nitrogen (N) removal have been successfully isolated from paddy soil in our lab. When peptone or ammonium sulfate as sole N source, no significant difference in gene expression related to nitrification and denitrification of the strains was found according to the transcriptome analysis. The expression of phosphomethylpyrimidine synthase (thiC), ABC transporter substrate-binding protein, branched-chain amino acid ABC transporter substrate-binding protein, and RNA polymerase (rpoE) in HNDS-1 were significantly upregulated when used peptone as N source, while the expression of exopolysaccharide production protein (yjbE), RNA polymerase (rpoC), glutamate synthase (gltD) and ABC-type branched-chain amino acid transport systems in HNDS-6 were significantly upregulated. This indicated that these two strains are capable of using organic N and converting it into NH 4 + -N, then utilizing NH 4 + -N to synthesize amino acids and proteins for their own growth, and strain HNDS-6 can also remove NH 4 + -N through nitrification and denitrification., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

The tolerance of ash trees against the pathogen Hymenoscyphus fraxineus seems to be associated with the occurrence of specific microbial taxa on leaves. A group of bacterial isolates, primarily identified on tolerant trees, was investigated with regard to their taxonomic classification and their potential to suppress the ash dieback pathogen. Examination of OGRI values revealed a separate species position. A phylogenomic analysis, based on orthologous and marker genes, indicated a separate genus position along with the species Achromobacter aestuarii. Furthermore, analysis of the ratio of average nucleotide identities and genome alignment fractions demonstrated genomic dissimilarities typically observed for inter-genera comparisons within this family. As a result of these investigations, the strains are considered to represent a separate species within a new genus, for which the name Schauerella fraxinea gen. nov., sp. nov. is proposed, with the type strain B3P038 T (=LMG 33092  T  = DSM 115926  T ). Additionally, a reclassification of the species Achromobacter aestuarii as Schauerella aestuarii comb. nov. is proposed. In a co-cultivation assay, the strains were able to inhibit the growth of a H. fraxineus strain. Accordingly, a functional analysis of the genome of S. fraxinea B3P038 T revealed genes mediating the production of antifungal substances. This potential, combined with the prevalent presence in the phyllosphere of tolerant ash trees, makes this group interesting for an inoculation experiment with the aim of controlling the pathogen in an integrative approach. For future field trials, a strain-specific qPCR system was developed to establish an efficient method for monitoring the inoculation success., (Copyright © 2024 The Authors. Published by Elsevier GmbH.. All rights reserved.)

Background: Achromobacter spp. are opportunistic pathogens, mostly infecting immunocompromised patients and patients with cystic fibrosis (CF) and considered as difficult-to-treat pathogens due to both intrinsic resistance and the possibility of acquired antimicrobial resistance. Species identification remains challenging leading to imprecise descriptions of resistance in each taxon. Cefiderocol is a broad-spectrum siderophore cephalosporin increasingly used in the management of Achromobacter infections for which susceptibility data remain scarce. We aimed to describe the susceptibility to cefiderocol of a collection of Achromobacter strains encompassing different species and isolation sources from CF or non-CF (NCF) patients., Methods: We studied 230 Achromobacter strains (67 from CF, 163 from NCF patients) identified by nrdA gene-based analysis, with available susceptibility data for piperacillin-tazobactam, meropenem and trimethoprim-sulfamethoxazole. Minimal inhibitory concentrations (MICs) of cefiderocol were determined using the broth microdilution reference method according to EUCAST guidelines., Results: Strains belonged to 15 species. A. xylosoxidans represented the main species (71.3%). MICs ranged from ≤ 0.015 to 16 mg/L with MIC 50/90 of ≤ 0.015/0.5 mg/L overall and 0.125/2 mg/L against 27 (11.7%) meropenem-non-susceptible strains. Cefiderocol MICs were not related to CF/NCF origin or species although A. xylosoxidans MICs were statistically lower than those of other species considered as a whole. Considering the EUCAST non-species related breakpoint (2 mg/L), 228 strains (99.1%) were susceptible to cefiderocol. The two cefiderocol-resistant strains (A. xylosoxidans from CF patients) represented 3.7% of meropenem-non-susceptible strains and 12.5% of MDR strains., Conclusions: Cefiderocol exhibited excellent in vitro activity against a large collection of accurately identified Achromobacter strains, irrespective of species and origin., (© 2024. The Author(s).)

Polycyclic aromatic hydrocarbons (PAHs) are considered substances of potential human health hazards because of their resistance to biodegradation and carcinogenic index. Chrysene is a PAH with a high molecular weight (HMW) that poses challenges for its elimination from the environment. However, bacterial degradation is an effective, environmentally friendly, and cost-effective solution. In our study, we isolated a potential chrysene-degrading bacteria from crude oil-contaminated seawater (Bizerte, Tunisia). Based on 16SrRNA analysis, the isolate S5 was identified as Achromobacter aegrifaciens. Furthermore, the results revealed that A. aegrifaciens S5 produced a biofilm on polystyrene at 20 °C and 30 °C, as well as at the air-liquid (A-L) interface. Moreover, this isolate was able to swim and produce biosurfactants with an emulsification activity (E24%) over 53%. Chrysene biodegradation by isolate S5 was clearly assessed by an increase in the total viable count. Confirmation was obtained via gas chromatography-mass spectrometry (GC-MS) analyses. A. aegrifaciens S5 could use chrysene as its sole carbon and energy source, exhibiting an 86% degradation of chrysene on day 7. In addition, the bacterial counts reached their highest level, over 25 × 10 20 CFU/mL, under the conditions of pH 7.0, a temperature of 30 °C, and a rotary speed of 120 rpm. Based on our findings, A. aegrifaciens S5 can be a potential candidate for bioremediation in HMW-PAH-contaminated environments., (© 2023. The Author(s), under exclusive licence to Springer Nature Switzerland AG.)

Achromobacter species are increasingly being detected in cystic fibrosis (CF) patients, where they can establish chronic infections by adapting to the lower airway environment. To better understand the mechanisms contributing to a successful colonization by Achromobacter species, we sequenced the whole genome of 54 isolates from 26 patients with occasional and early/late chronic lung infection. We performed a phylogenetic analysis and compared virulence and resistance genes, genetic variants and mutations, and hypermutability mechanisms between chronic and occasional isolates. We identified five Achromobacter species as well as two non-affiliated genogroups (NGs). Among them were the frequently isolated Achromobacter xylosoxidans and four other species whose clinical importance is not yet clear: Achromobacter insuavis, Achromobacter dolens, Achromobacter insolitus and Achromobacter aegrifaciens . While A. insuavis and A. dolens were isolated only from chronically infected patients and A. aegrifaciens only from occasionally infected patients, the other species were found in both groups. Most of the occasional isolates lacked functional genes involved in invasiveness, chemotaxis, type 3 secretion system and anaerobic growth, whereas the great majority (>60%) of chronic isolates had these genomic features. Interestingly, almost all ( n =22/23) late chronic isolates lacked functional genes involved in lipopolysaccharide production. Regarding antibiotic resistance, we observed a species-specific distribution of blaOXA genes, confirming what has been reported in the literature and additionally identifying blaOXA-2 in some A. insolitus isolates and observing no blaOXA genes in A. aegrifaciens or NGs. No significant difference in resistance genes was found between chronic and occasional isolates. The results of the mutator genes analysis showed that no occasional isolate had hypermutator characteristics, while 60% of early chronic (<1 year from first colonization) and 78% of late chronic (>1 year from first colonization) isolates were classified as hypermutators. Although all A. dolens, A. insuavis and NG isolates presented two different mutS genes, these seem to have a complementary rather than compensatory function. In conclusion, our results show that Achromobacter species can exhibit different adaptive mechanisms and some of these mechanisms might be more useful than others in establishing a chronic infection in CF patients, highlighting their importance for the clinical setting and the need for further studies on the less clinically characterized Achromobacter species.

Achromobacter species, which are recognized as emerging pathogens isolated from patients with cystic fibrosis, are capable of forming biofilm in the respiratory tract in patients and innate multidrug resistance to antimicrobials. CSAs are cationic salt derivatives that mimic the activity of antimicrobial peptides and exhibit antimicrobial activity against bacteria. In this study, the in vitro activities of various ceragenins against Achromobacter-species biofilms were investigated comparatively with a conventional antibiotic (meropenem). Biofilm-formation inhibition and biofilm-adhesion inhibition were investigated on five strong biofilm-producing strains. The lowest MIC 50 result was obtained with CSA-13. All of the tested CSAs showed significant biofilm inhibitory activity in the manner of a time- and concentration-dependent effect. To the best of our knowledge, this is the first article to evaluate the antibacterial and antibiofilm activities of tested CSAs against Achromobacter species.

Achromobacter spp. are emerging pathogens in patients with cystic fibrosis (CF) and Achromobacter spp. caused infections are associated with more severe disease outcomes and high intrinsic antibiotic resistance. While conventional CF pathogens are studied extensively, little is known about the genetic determinants leading to antibiotic resistance and the genetic adaptation in Achromobacter spp. infections. Here, we analysed 101 Achromobacter spp. genomes from 51 patients with CF isolated during the course of up to 20 years of infection to identify within-host adaptation, mutational signatures and genetic variation associated with increased antibiotic resistance. We found that the same regulatory and inorganic ion transport genes were frequently mutated in persisting clone types within and between Achromobacter species, indicating convergent genetic adaptation. Genome-wide association study of six antibiotic resistance phenotypes revealed the enrichment of associated genes involved in inorganic ion transport, transcription gene enrichment in β-lactams, and energy production and translation gene enrichment in the trimethoprim/sulfonamide group. Overall, we provide insights into the pathogenomics of Achromobacter spp. infections in patients with CF airways. Since emerging pathogens are increasingly recognized as an important healthcare issue, our findings on evolution of antibiotic resistance and genetic adaptation can facilitate better understanding of disease progression and how mutational changes have implications for patients with CF.

Purpose: To investigate a cluster of corneoscleral rim cultures positive for Achromobacter species over a 6-month period at Massachusetts Eye and Ear., Methods: An increased rate of positive corneal donor rim cultures was noted at Massachusetts Eye and Ear between July and December 2017. Positive cultures were subjected to identification and antimicrobial susceptibility testing by phenotypic (MicroScan WalkAway) and genotypic (16S rDNA sequencing) methods. Samples of the eye wash solution (GeriCare) used in the eye bank were also evaluated. Antimicrobial activity of Optical-GS against Achromobacter spp. at 4°C and 37°C was assessed by time-kill kinetics assay., Results: Of 99 donor rims cultured, 14 (14.1%) grew bacteria with 11 (78.6%) due to uncommon nonfermenting Gram-negative bacilli. These had been identified by standard automated methods as Achromobacter (n = 3), Alcaligenes (n = 3), Ralstonia (n = 2), Pseudomonas (n = 2), and Stenotrophomonas (n = 1). Eight of these 11 isolates were subsequently available for molecular identification, and all were identified as Achromobacter spp. Six bottles of eyewash solution were evaluated and were positive for abundant Achromobacter spp. (3.4 × 105 ± 1.1 CFU/mL). Optisol-GS had no bactericidal activity against Achromobacter spp. at 4°C after 24-hour incubation but was bactericidal at 37°C. None of the patients who had received the contaminated corneas developed postoperative infection., Conclusions: An eyewash solution arising from a single lot was implicated in the contamination of donor rims by Achromobacter spp. The isolates were able to survive in the Optisol-GS medium at the recommended storage temperature. This highlights the need to continue improving protocols for tissue preparation and storage., Competing Interests: The authors have no conflicts of interest to disclose., (Copyright © 2020 Wolters Kluwer Health, Inc. All rights reserved.)

Objectives: Achromobacter spp. are emerging pathogens in respiratory samples from cystic fibrosis patients. The current reference methods (nrdA-sequencing or multilocus sequence typing) can identify 18 species which are often misidentified by conventional techniques as A. xylosoxidans. A few studies have suggested that matrix-assisted laser desorption/ionization-time-of-flight mass spectrometry (MALDI-TOF/MS) provides accurate identification of the genus but not of species. The aims of this study were (a) to generate a database for MALDI-TOF/MS Bruker including the 18 species, (b) to evaluate the suitability of the database for routine laboratory identification, and (c) to compare its performance with that of the currently available Bruker default database., Methods: A total of 205 isolates belonging to the 18 species identified by nrdA sequencing were used to build a local database. Main spectra profiles (MSPs) were created according to Bruker's recommendations for each isolate with the Biotyper software. Performance of the default Bruker database and ours for routine use were compared by testing 167 strains (including 38 isolates used from MSP creation) belonging to the 18 species identified by nrdA sequencing directly from colonies cultivated on various media., Results: Our new database accurately identified 99.4% (166/167) of the isolates from the 18 species (score ≥2.0) versus only 50.9% (85/167) with the Bruker database. In the Bruker database 17.3% of the isolates (29/167) were incorrectly identified as another species despite a score of ≥2.0., Conclusions: The use of MALDI-TOF/MS in combination with a database developed with samples from 18 Achromobacter species provides rapid and accurate identification. This tool could be used to help future clinical studies., (Copyright © 2020 European Society of Clinical Microbiology and Infectious Diseases. Published by Elsevier Ltd. All rights reserved.)

Several members of the Gram-negative environmental bacterial genus Achromobacter are associated with serious infections, with Achromobacter xylosoxidans being the most common. Despite their pathogenic potential, little is understood about these intrinsically drug-resistant bacteria and their role in disease, leading to suboptimal diagnosis and management. Here, we performed comparative genomics for 158 Achromobacter spp. genomes to robustly identify species boundaries, reassign several incorrectly speciated taxa and identify genetic sequences specific for the genus Achromobacter and for A. xylosoxidans . Next, we developed a Black Hole Quencher probe-based duplex real-time PCR assay, Ac-Ax, for the rapid and simultaneous detection of Achromobacter spp. and A. xylosoxidans from both purified colonies and polymicrobial clinical specimens. Ac-Ax was tested on 119 isolates identified as Achromobacter spp. using phenotypic or genotypic methods. In comparison to these routine diagnostic methods, the duplex assay showed superior identification of Achromobacter spp. and A. xylosoxidans , with five Achromobacter isolates failing to amplify with Ac-Ax confirmed to be different genera according to 16S rRNA gene sequencing. Ac-Ax quantified both Achromobacter spp. and A. xylosoxidans down to ~110 genome equivalents and detected down to ~12 and ~1 genome equivalent(s), respectively. Extensive in silico analysis, and laboratory testing of 34 non- Achromobacter isolates and 38 adult cystic fibrosis sputa, confirmed duplex assay specificity and sensitivity. We demonstrate that the Ac-Ax duplex assay provides a robust, sensitive and cost-effective method for the simultaneous detection of all Achromobacter spp. and A. xylosoxidans and will facilitate the rapid and accurate diagnosis of this important group of pathogens.

In this study, we selected and characterized different pesticide-tolerant bacteria isolated from a biomixture of a biopurification system that had received continuous applications of a pesticides mixture. The amplicon analysis of biomixture reported that the phyla Proteobacteria, Firmicutes, Bacteroidetes and Actinobacteria were predominant. Six strains grew in the presence of chlorpyrifos and iprodione. Biochemical characterization showed that all isolates were positive for esterase, acid phosphatase, among others, and they were identified as Pseudomonas, Rhodococcus and Achromobacter based on molecular and proteomic analysis. Bacterial growth decreased as both pesticide concentrations increased from 10 to 100 mg L-1 in liquid culture. The Achromobacter sp. strain C1 showed the best chlorpyrifos removal rate of 0.072-0.147 d-1 a half-life of 4.7-9.7 d and a maximum metabolite concentration of 2.10 mg L-1 at 120 h. On the other hand, Pseudomonas sp. strain C9 showed the highest iprodione removal rate of 0.100-0.193 d-1 a half-life of 4-7 d and maximum metabolite concentration of 0.95 mg L-1 at 48 h. The Achromobacter and Pseudomonas strains showed a good potential as chlorpyrifos and iprodione-degrading bacteria., Competing Interests: The authors have declared that no competing interests exist.

Different MALDI-TOF MS databases were evaluated for the identification of Achromobacter species. The in-house and extended database generated in this study rendered more accurate identification (58/64 and 57/64 isolates, respectively) in comparison with the Bruker commercial database (42/64 isolates), especially in those infrequent species that are not available or poorly represented., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Different phenotype-based techniques and molecular tools were used to describe the distribution of different Achromobacter species in patients with cystic fibrosis (CF) in Argentina, and to evaluate their antibiotic resistance profile. Phenotypic identification was performed by conventional biochemical tests, commercial galleries and MALDI-TOF MS. Genetic approaches included the detection of A. xylosoxidans specific marker bla oxa-114 , the amplification and sequencing of the 16S rRNA gene, nrdA and bla OXA complete sequence, and MLST analysis. Phenotypic approaches, even MALDI-TOF, rendered inconclusive or misleading results. On the contrary, concordant results were achieved with the nrdA sequencing or sequence type (ST) analysis, and the complete bla OXA sequencing, allowing a reliable discrimination of different Achromobacter species. A. xylosoxidans accounted for 63% of Achromobacter infections and A. ruhlandii accounted for 17%. The remaining species corresponded to A. insuavis, A. dolens, A. marplatensis and A. pulmonis. Antimicrobial susceptibilities were determined by the agar dilution method according to CLSI guidelines. Piperacillin, piperacillin/tazobactam and carbapenems were the most active antibiotics. However, the emergence of carbapenem-resistant isolates was detected. In conclusion, prompt and accurate identification tools were necessary to determine that different Achromobacter species may colonize/infect the airways of patients with CF. Moreover, antimicrobial therapy should be administered based on the susceptibility profile of individual Achromobacter sp. isolates., (Copyright © 2019 Asociación Argentina de Microbiología. Publicado por Elsevier España, S.L.U. All rights reserved.)

Strain LMG 30378 T was isolated from a hydrogen-oxidizing bacteria enrichment reactor inoculated with forest soil. Phylogenetic analysis based on the 16S rRNA gene sequence indicated that this strain belonged to the genus Achromobacter . Multilocus sequence analysis combined with sequence analysis of a 765 bp nrd A gene fragment both showed Achromobacter agilis LMG 3411 T and Achromobacter denitrificans LMG 1231 T to be the closest-related neighbours to strain LMG 30378 T . Genome sequence analysis revealed a draft genome of 6.81 Mb with a G+C content of 67.2 mol%. In silico DNA-DNA hybridization with A. denitrificans LMG 1231 T and A. agilis LMG 3411 T showed 42.7 and 42.5% similarity, respectively, confirming that strain LMG 30378 T represented a novel Achromobacter species. Phenotypic and metabolic characterization revealed acid phosphatase activity and the absence of phosphoamidase activity as distinctive features. The draft genome composes all necessary metabolic components to fix carbon dioxide and to oxidize molecular hydrogen, suggesting that strain LMG 30378 T is a key organism in the enrichment reactor. Together, these data demonstrate that strain LMG 30378 T represents a novel species of the genus Achromobacter , for which the name Achromobacter veterisilvae sp. nov. is proposed. The type strain is LMG 30378 T (=CCUG 71558 T ).

Exploration of diverse environmental samples for plant growth-promoting microbes to fulfill the increasing demand for sustainable agriculture resulted in increased use of bacterial biofertilizer. We aimed for the isolation of plant growth-promoting as well as antibiotic sensitive bacteria from bovine manure samples. The basic theme of our study is to highlight potentials of bacteria in manure and the unchecked risk associated with the application of manure i.e. introducing antibiotic-resistant microbial flora, as fertilizer. Fifty-two, morphologically distinct isolates; from eight different manure samples, were subjected to plant growth-promoting parametric tests along with antibiotic resistance. Thirteen antibiotic sensitive bacterial strains with potentials of plant growth promotion further characterized by 16S rRNA ribotyping and the identified genera were Stenotrophomonas, Achromobacter, Pseudomonas, and Brevibacillus. Successful radish seeds germination under sterile in-vitro conditions showed the potential of selected bacterial isolates as plant growth-promoting bacteria. The results of this study confirmed plant growth-promoting characteristics of bovine manures' bacterial strains along with an alarming antibiotic resistance load which comprises 75% of bacterial isolated population. Our study showed distinct results of un-explored manure bacterial isolates for plant growth promotion and flagged ways associated with unchecked manure application in agriculture soil through high load of antibiotic resistant bacteria., Competing Interests: The authors have declared that no competing interests exist.

Background: Bacteria of the Achromobacter genus, more particularly xylosoxidans species, are responsible for various healthcare associated infections (HAI) which are increasingly described since the last decade. Cystic fibrosis (CF) patients are considered as potential reservoirs in hospitals. We performed a retrospective study to estimate the frequencies of Achromobacter spp. HAI among patients from French West Indies, to determine characteristics of infected patients and establish a possible link between CF and infections., Methods: All adults with at least one Achromobacter spp. positive sample and infection criteria in accordance with European official definitions of HAI, hospitalized in University Hospital of Martinique from 2006 to 2016 for more than 48 h, were included. Patient clinical features, immune status and underlying diseases were obtained from medical files. A list of CF patients was given by clinicians. Antibiotic-susceptibility profiles of the strains were determined using an automated method., Results: Mean incidence density was 0.038/1000 days of hospitalization. Achromobacter spp. HAI evolved as an endemic situation with a low but pretty much stable incidence rate over the 11-year observation period. An epidemic peak was noticed in 2013. Among the 66 included patients, 56.1% were immunocompetent and no one had CF. Pneumonia and bacteraemia were the two main HAI. Among the 79 isolated strains, 92.4% were resistant to at least 1 major antibiotic and 16.4% met the definition of multidrug-resistant bacteria., Conclusions: This microorganism, little known in our country because of the scarcity of CF patients, represents a threat for both immunosuppressed and immunocompetent patients and a therapeutic challenge because of its high resistance.

The airborne route is a potential pathway in the person-to-person transmission of bacterial strains among cystic fibrosis (CF) populations. In this cross-sectional study, we investigate the physical properties and survival of common non- Pseudomonas aeruginosa CF pathogens generated during coughing. We conclude that Gram-negative bacteria and Staphylococcus aureus are aerosolised during coughing, can travel up to 4 m and remain viable within droplet nuclei for up to 45 min. These results suggest that airborne person-to-person transmission is plausible for the CF pathogens we measured., Competing Interests: Competing interests: During conduct of the study: SCB reports grants from Cystic Fibrosis Foundation Therapeutics, USA, and The Prince Charles Hospital Foundation and outside of the submitted work, travel support to attend conferences from Novartis and Gilead and meetings for clinical trials sponsored by Vertex, Abbvie, Raptor. LDK reports grants from the NHMRC during the conduct of the study. GRJ reports grants from Cystic Fibrosis Foundation Therapeutics, USA, and The Prince Charles Hospital Foundation during the conduct of the study. CEW reports outside of the submitted work: research grant from Novo Nordisk Pharmaceuticals; honorarium fees as speaker for Vertex, DKBmed; honorarium for consulting work (BMJ, Vertex), advisory board (Vertex); to present at conference (Novartis), attendance at meetings (University of Miami), Associate Editor duties (Thorax) and travel support to attend meetings for clinical trials sponsored by Vertex. CEW is Associate Editor Thorax and Associate Editor Respirology. MEW reports outside of submitted work: travel support to attend clinical trial meetings sponsored by Vertex and Galapagos., (© Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2019. All rights reserved. No commercial use is permitted unless otherwise expressly granted.)

Objectives: Achromobacter spanius is a newly described, non-fermenting, Gram-negative, coccoid pathogen isolated from human blood. Whole-genome sequencing of the A. spanius type strain was performed to investigate the mechanism of pathogenesis of this strain at a genomic level., Methods: The complete genome of A. spanius type strain DSM 23806 T was sequenced using single-molecule real-time (SMRT) DNA sequencing., Results: The complete genome of DSM 23806 T consists of one circular DNA chromosome of 6425783bp with a G+C content of 64.26%. The entire genome contains 5804 predicted coding sequences (CDS) and 55 tRNAs. Genomic island (GI) analysis showed that this strain encodes several important pathogenesis- and resistance-related genes., Conclusions: These results strongly suggest that GIs provide some fitness advantages in A. spanius type strain DSM 23806 T . This report provides an extensive understanding of A. spanius at a genomic level as well as an understanding of the evolution of A. spanius., (Copyright © 2018 International Society for Chemotherapy of Infection and Cancer. Published by Elsevier Ltd. All rights reserved.)

Purpose: Cystic fibrosis (CF) patients are susceptible to infection with Achromobacter spp., although its clinical significance remains controversial. The aim of this study was to investigate the clinical impact of infection with Achromobacter spp. in CF patients., Methods: CF outpatients with multiple sputum cultures and follow-up lung function tests were assigned to the case group (infected with Achromobacter spp.) or the control group (never infected with Achromobacter spp.) according to the isolation of Achromobacter spp. The Achromobacter spp. group included two subgroups, taking into consideration whether the isolation of Achromobacter spp. was intermittent or chronic. Baseline lung function tests and longitudinal behaviour were examined in relation to Achromobacter spp. status., Results: A total of 190 CF patients were treated from January 2003 to December 2015 in the CF unit and 21 (11 %) had at least one positive culture for Achromobacter spp. Of these, 11/21 (52.4 %) patients were chronically infected with Achromobacter spp. An analysis of changes during follow-up showed the annual rate of FEV1 decline: -2.3±1.6 % in the Achromobacter spp. group compared to -1.1±0.9 % (P=0.02) in the control group. The chronically infected group also had a significantly greater decline in FEV1 compared to the control group (-2.9±1.9 vs -1.1±0.9; P=0.04). The mean number of annual pulmonary exacerbations during the study period was significantly higher in the case group (1.9±0.9 vs 1.1±0.8; P=0.03)., Conclusions: The Achromobacter spp. status in CF shows a trend towards more severe airflow obstruction and an association with accelerated decline in lung function parameters.

Honeybees are prone to parasite and pathogen infestations/infections due to their social colony life. Bacterial pathogens in particular lead to destructive infections of the brood. European foulbrood is caused by the bacterium Melissococcus plutonius in combination with several other Gram-positive bacteria (Achromobacter eurydice, Bacillus pumilus, Brevibacillus laterosporus, Enterococcus faecalis, Paenibacillus alvei, Paenibacillus dendritiformis) involved as secondary invaders following the initial infection. More than a century ago, A. eurydice was discovered to be associated with European foulbrood and morphologically and biochemically characterized. However, since the 1950s-1960s, only a few studies are known covering the biological relevance of this bacterium. Here, we review the biology, ecology, morphology, and biochemistry and discuss the still unclear systematic classification of A. eurydice.

Objectives: Bacteria belonging to the genera Ochrobactrum and Achromobacter are bacteria considered opportunistic, causing infections mainly in immunocompromised patients. β-lactamases are the main cause of resistance to β-lactam antibiotics. This study aimed to investigate the antimicrobial resistance profile and the presence of β-lactamases encoding genes in Ochrobactrum sp. and Achromobacter sp. isolated from Brazilian soils., Methods: Soil samples from the five regions of Brazil were collected for the isolation of bacteria, which were identified molecularly and then, the minimum inhibitory concentration and detection of β-lactamases encoding genes were performed., Results: High-level of resistance to β-lactam antibiotics and different β-lactamases encoding genes were found (bla CTX-M-Gp1 , bla SHV , bla OXA-1-like and bla KPC ), including the first report of the presence of bla KPC in bacteria belonging to the genera Ochrobactrum and Achromobacter., Conclusion: The results showed that the bacteria from this study, belonging to genera Ochrobactrum and Achromobacter isolated from soil, harbor different β-lactamases encoding genes and can act as a reservoir of these genes., (Copyright © 2017 International Society for Chemotherapy of Infection and Cancer. Published by Elsevier Ltd. All rights reserved.)

Rationale: Achromobacter species are increasingly identified in individuals with cystic fibrosis (CF), but the clinical outcomes in these patients remain poorly understood., Objectives: We aimed to determine the association of Achromobacter infection on clinical outcomes in pediatric and adult patients with CF., Methods: A cohort study of pediatric and adult patients with CF was conducted from 1997 to 2014 in Toronto, Ontario, Canada. Achromobacter spp. infection was categorized as no history of infection, intermittent infection, and chronic infection (two or more positive cultures in the preceding 12 months). Cox models were used to estimate risk of death or transplantation. Mixed-effects models were used to assess odds of pulmonary exacerbations and effect on lung function (FEV 1 %) by Achromobacter spp., Results: A total of 1,103 patients were followed-up over the course of 18 years; 88 patients (7.3%) had one or more culture for Achromobacter species. Chronic Achromobacter infection was associated with a greater risk of death or transplantation compared with in patients with no history of infection (adjusted hazard ratio, 2.03; 95% confidence interval, 1.05-3.95; P = 0.036). Pulmonary exacerbations were more common in patients with chronic infection, but after adjusting for confounding factors, the effect was no longer significant. The chronic group had lower FEV 1 %, but it did not worsen after developing chronic infection., Conclusions: Patients with CF and chronic Achromobacter infection are at increased risk of death or transplantation.

Achromobacter species are increasingly being detected in cystic fibrosis (CF) patients, with an unclear epidemiology and impact. We studied a cohort of patients attending a Canadian adult CF clinic who had positive sputum cultures for Achromobacter species in the period from 1984 to 2013. Infection was categorized as transient or persistent (≥50% positive cultures for 1 year). Those with persistent infection were matched 2:1 with age-, sex-, and time-matched controls without a history of Achromobacter infection, and mixed-effects models were used to assess pulmonary exacerbation (PEx) frequency and lung function decline. Isolates from a biobank were retrospectively assessed, identified to the species level by nrdA sequencing, and genotyped using pulsed-field gel electrophoresis (PFGE). Thirty-four patients (11% of those in our clinic), with a median age of 24 years (interquartile range [IQR], 20.3 to 29.8 years), developed Achromobacter infection. Ten patients (29%) developed persistent infection. Persistence did not denote permanence, as most patients ultimately cleared infection, often after years. Patients were more likely to experience PEx at incident isolation than at prior or subsequent visits (odds ratio [OR], 2.7 [95% confidence interval {CI}, 1.2 to 6.7]; P = 0.03). Following persistent infection, there was no difference in annual lung function decline (-1.08% [95% CI, -2.73 to 0.57%] versus -2.74% [95% CI, -4.02 to 1.46%]; P = 0.12) or the odds of PEx (OR, 1.21 [95% CI, 0.45 to 3.28]; P = 0.70). Differential virulence among Achromobacter species was not observed, and no cases of transmission occurred. We demonstrated that incident Achromobacter infection was associated with a greater risk of PEx; however, neither transient nor chronic infection was associated with a worsened long-term prognosis. Large, multicenter studies are needed to clarify the clinical impact, natural history, and transmissibility of Achromobacter ., (Copyright © 2017 American Society for Microbiology.)

Background: Although culture-independent methods have paved the way for characterization of the lung microbiome, the dynamic changes in the lung microbiome from neonatal stage to adult age have not been investigated., Results: In this study, we tracked changes in composition and diversity of the lung microbiome in C57BL/6N mice, starting from 1-week-old neonates to 8-week-old mice. Towards this, the lungs were sterilely excised from mice of different ages from 1 to 8 weeks. High-throughput DNA sequencing of the 16S rRNA gene followed by composition and diversity analysis was utilized to decipher the microbiome in these samples. Microbiome analysis suggests that the changes in the lung microbiome correlated with age. The lung microbiome was primarily dominated by phyla Proteobacteria, Firmicutes, Bacteroidetes, and Actinobacteria in all the stages from week 1 to week 8 after birth. Although Defluvibacter was the predominant genus in 1-week-old neonatal mice, Streptococcus became the dominant genus at the age of 2 weeks. Lactobacillus, Defluvibacter, Streptococcus, and Achromobacter were the dominant genera in 3-week-old mice, while Lactobacillus and Achromobacter were the most abundant genera in 4-week-old mice. Interestingly, relatively greater diversity (at the genus level) during the age of 5 to 6 weeks was observed as compared to the earlier weeks. The diversity of the lung microbiome remained stable between 6 and 8 weeks of age., Conclusions: In summary, we have tracked the development of the lung microbiome in mice from an early age of 1 week to adulthood. The lung microbiome is dominated by the phyla Proteobacteria, Firmicutes, Bacteroidetes, and Actinobacteria. However, dynamic changes were observed at the genus level. Relatively higher richness in the microbial diversity was achieved by age of 6 weeks and then maintained at later ages. We believe that this study improves our understanding of the development of the mice lung microbiome and will facilitate further analyses of the role of the lung microbiome in chronic lung diseases.

A novel strain DCY105 T was isolated from soil collected from the rhizosphere of ginseng (Panax ginseng), in Gochang, Republic of Korea. Strain DCY105 T is Gram-reaction-negative, white, non-motile, non-flagellate, rod-shaped and aerobic. The bacteria grow optimally at 30°C, pH 6.5-7.0 and in the absence of NaCl. Phylogenetically, strain DCY105 T is most closely related to Achromobacter marplatensis LMG 26219 T (96.81%). The DNA G+C content of strain DCY105 T was 64.4 mol%. Ubiquinone 8 was the major respiratory quinone, and phosphatidylethanolamine, phosphatidylglycerol, and diphosphatidylglycerol were amongst the major polar lipids. C 16:00 , C 8:0 3OH and iso-C 17:0 3OH were identified as the major fatty acids present in DCY105 T . The results of physiological and biochemical tests allowed strain DCY105 T to be differentiated phenotypically from other recognized species belonging to the genus Achromobacter. Therefore, it is suggested that the newly isolated organism represents a novel species, for which the name Achromobacter panacis sp. nov. is proposed with the type strain designated as DCY105 T (=CCTCCAB 2015193 T =KCTC 42751 T ).

Several bacteria have been isolated to degrade 4-chloronitrobenzene. Degradation of 4-chloronitrobenzene by Cupriavidus sp. D4 produces 5-chloro-2-picolinic acid as a dead-end by-product, a potential pollutant. To date, no bacterium that degrades 5-chloro-2-picolinic acid has been reported. Strain f1, isolated from a soil polluted by 4-chloronitrobenzene, was able to co-metabolize 5-chloro-2-picolinic acid in the presence of ethanol or other appropriate carbon sources. The strain was identified as Achromobacter sp. based on its physiological, biochemical characteristics, and 16S rRNA gene sequence analysis. The organism completely degraded 50, 100 and 200 mg L -1 of 5-chloro-2-picolinic acid within 48, 60, and 72 h, respectively. During the degradation of 5-chloro-2-picolinic acid, Cl - was released. The initial metabolic product of 5-chloro-2-picolinic acid was identified as 6-hydroxy-5-chloro-2-picolinic acid by LC-MS and NMR. Using a mixed culture of Achromobacter sp. f1 and Cupriavidus sp. D4 for degradation of 4-chloronitrobenzen, 5-chloro-2-picolinic acid did not accumulate. Results infer that Achromobacter sp. f1 can be used for complete biodegradation of 4-chloronitrobenzene in remedial applications.

Achromobacter insolitus is a newly described, Gram-negative, small (1-2 mm long) and coccoid pathogen that has been isolated from leg wound. Due to its potential threat to human beings, the type strain of this species LMG 6003T was completely sequenced in this study. The genomic analysis revealed that the genome of LMG 6003T consists of one circular DNA chromosome of 6 492 697 bp with a GC content of 65.10%. The entire genome contains 6208 predicted coding genes, 61 tRNAs and 13 rRNA genes. Comparative genome analysis between LMG 6003T and another selected 10 sequenced Achromobacter revealed that 725 genes only exist in LMG 6003T. In particular, these genes include several important pathogenic-related genes such as Type IV prepilin peptidase (TadV/CpaA), Type VI secretion lipoprotein (VasD) and type 1 fimbriae major subunit (FimA). Genomic island (GI) analysis also suggests the existence of GIs in LMG 6003T. All these results strongly suggest the unique genomic features in LMG 6003T against other Achromobacter species. This report will provide us with an extended understanding of A. insolitus at the genomic level and would be helpful for understanding the evolution of the Achromobacter genus.

Achromobacter spp. are recognized as emerging pathogens in hospitalized as well as in cystic fibrosis (CF) patients. From 2012 to 2015, we collected 69 clinical isolates (41 patient) of Achromobacter spp. from 13 patients with CF (CF isolates, n = 32) and 28 patients receiving care for other health conditions (non-CF isolates, n = 37). Molecular epidemiology and virulence potential of isolates were examined. Antimicrobial susceptibility, motility, ability to form biofilms and binding affinity to mucin, collagen, and fibronectin were tested to assess their virulence traits. The nrdA gene sequencing showed that A. xylosoxidans was the most prevalent species in both CF and non-CF patients. CF patients were also colonized with A. dolens/A. ruhlandii, A. insuavis , and A. spiritinus strains while non-CF group was somewhat less heterogenous, although A. insuavis, A. insolitus , and A. piechaudii strains were detected beside A. xylosoxidans . Three strains displayed clonal distribution, one among patients from the CF group and two among non-CF patients. No significant differences in susceptibility to antimicrobials were observed between CF and non-CF patients. About one third of the isolates were classified as strong biofilm producers, and the proportion of CF and non-CF isolates with the ability to form biofilm was almost identical. CF isolates were less motile compared to the non-CF group and no correlation was found between swimming phenotype and biofilm formation. On the other hand, CF isolates exhibited higher affinity to bind mucin, collagen, and fibronectin. In generall, CF isolates from our study exhibited in vitro properties that could be of importance for the colonization of CF patients.

Achromobacter animicus (A. animicus) is an aerobic, motile, gram-negative, non-fermenting small bacillus that can also grow anaerobically with potassium nitrate. It has been isolated from sputum of humans suffering from respiratory infections. Literature regarding the role of A. animicus in wound infections is limited. We report a first case of a chronic post-traumatic wound infection caused by a multidrug-resistant A. animicus in a street child from Africa and accompanied diagnostic challenges., (Copyright © 2017 Elsevier Inc. All rights reserved.)

Thermo-solar plants use eutectic mixtures of diphenyl ether (DE) and biphenyl (BP) as heat transfer fluid (HTF). Potential losses of HTF may contaminate soils and bioremediation is an attractive tool for its treatment. DE- or BP-degrading bacteria are known, but up to now bacteria able to degrade HTF mixture have not been described. Here, five bacterial strains which are able to grow with HTF or its separate components DE and BP as sole carbon sources have been isolated, either from soils exposed to HTF or from rhizospheric soils of plants growing near a thermo-solar plant. The organisms were identified by 16S rRNA gene sequencing as Achromobacter piechaudii strain BioC1, Pseudomonas plecoglossicida strain 6.1, Pseudomonas aeruginosa strains HBD1 and HBD3, and Pseudomonas oleovorans strain HBD2. Activity of 2,3-dihydroxybiphenyl dioxygenase (BphC), a key enzyme of the biphenyl upper degradation pathway, was detected in all isolates. Pseudomonas strains almost completely degraded 2000ppm HTF after 5-day culture, and even tolerated and grew in the presence of 150,000ppm HTF, being suitable candidates for in situ soil bioremediation. Degradation of both components of HTF is of particular interest since in the DE-degrader Sphingomonas sp. SS3, growth on DE or benzoate was strongly inhibited by addition of BP., (Copyright © 2016 Elsevier B.V. All rights reserved.)

Achromobacter spp. are opportunistic pathogens increasingly recovered from adult patients with cystic fibrosis (CF). We report the characterization of 122 Achromobacter spp. isolates recovered from 39 CF patients by multilocus sequence typing, virulence traits, and susceptibility to antimicrobials. Two species, A. xylosoxidans (77%) and A. ruhlandii (23%) were identified. All isolates showed a similar biofilm formation ability, and a positive swimming phenotype. By contrast, 4·3% and 44·4% of A. xylosoxidans and A. ruhlandii, respectively, exhibited a negative swarming phenotype, making the swimming and swarming abilities of A. xylosoxidans significantly higher than those of A. ruhlandii. A. xylosoxidans isolates from an outbreak clone also exhibited significantly higher motility. Both species were generally susceptible to ceftazidime, ciprofloxacin, imipenem and trimethoprim/sulphamethoxazole and there was no significant difference in susceptibility between isolates from chronic or sporadic infection. However, A. xylosoxidans isolates from chronic and sporadic cases were significantly more resistant to imipenem and ceftazidime than isolates of the outbreak clone.

In this study, a bacterial strain of Achromobacter sp. LZ35, which was capable of utilizing 2,4-dichlorophenoxyacetic acid (2,4-D) and 2-methyl-4-chlorophenoxy acetic acid (MCPA) as the sole sources of carbon and energy for growth, was isolated from the soil in a disused pesticide factory in Suzhou, China. The optimal 2,4-D degradation by strain LZ35 occurred at 30 °C and pH 8.0 when the initial 2,4-D concentration was 200 mg L -1 . Strain LZ35 harbored the conserved 2,4-D/alpha-ketoglutarate dioxygenase (96%) and 2,4-dichlorophenol hydroxylase (99%), and catabolized 2,4-D via the intermediate 2,4-dichlorophenol. The inoculation of 7.8 × 10 6  CFU g -1 soil of strain LZ35 cells to 2,4-D-contaminated soil could efficiently remove over 75 and 90% of 100 and 50 mg L -1 2,4-D in 12 days and significantly released the phytotoxicity of maize caused by the 2,4-D residue. This is the first report of an Achromobacter sp. strain that was capable of mineralizing both 2,4-D and MCPA. This study provides us a promising candidate for its application in the bioremediation of 2,4-D- or MCPA-contaminated sites.

Two Gram-staining-negative, strictly aerobic, rod-shaped bacteria, designated strains AVA-1T and AVA-2, were isolated from the root of Aloe vera (L.) Brum.f. derived from Chachoengsao Province, Thailand. The strains contained cytochrome oxidase and catalase activities. They grew in 4 % (w/v) NaCl, at a pH range of 6.0-9.0 (optimally at pH 7) and at 20-42 °C (optimally at 30-37 °C). The major isoprenoid quinone was ubiquinone with eight isoprene units (Q-8). The major fatty acids were C16 : 0 and C17 : 0 cyclo. On the basis of 16S rRNA gene sequence analysis, the strains represent a species belonging to the genus Achromobacter and are closely related to Achromobacter xylosoxidans NBRC 15126T (98.80 %), Achromobacter insolitus LMG 6003T (98.64 %), Achromobacter aminicus LMG 26690T (98.59 %), Achromobacter pulmonis LMG 26696T (98.58 %) and Achromobacter insuavis LMG 26845T (98.58 %). The DNA G+C content of strain AVA-1T was 66.5 mol%. The novel strains had low DNA-DNA relatedness values with related type strains. On the basis of the phenotypic and genotypic data obtained, the strains clearly represent a novel species, for which the name Achromobacter aloeverae sp. nov. is proposed. The type strain is strain AVA-1T (=LMG 29108T=NBRC 111463T=PCU 352T=TISTR 2383T).

Chronic colonization by opportunistic environmental bacteria is frequent in the airways of cystic fibrosis (CF) patients. Studies of Pseudomonas aeruginosa evolution during persistence have highlighted the emergence of pathoadaptive genotypes and phenotypes, leading to complex and diversified inpatient colonizing populations also observed at the intraspecimen level. Such diversity, including heterogeneity in resistance profiles, has been considered an adaptive strategy devoted to host persistence. Longitudinal genomic diversity has been shown for the emergent opportunistic pathogen Achromobacter, but phenotypic and genomic diversity has not yet been studied within a simple CF sputum sample. Here, we studied the genomic diversity and antimicrobial resistance heterogeneity of 132 Achromobacter species strains (8 to 27 strains of identical or distinct colonial morphotypes per specimen) recovered from the sputum samples of 9 chronically colonized CF patients. We highlighted the high within-sample and within-morphotype diversity of antimicrobial resistance (disk diffusion) and genomic (pulsed-field gel electrophoresis) profiles. No sputum sample included strains with identical pulsotypes or antibiotic susceptibility patterns. Differences in clinical categorization were observed for the 9 patients and concerned 3 to 11 antibiotics, including antibiotics recommended for use against Achromobacter Within-sample antimicrobial resistance heterogeneity, not predictable from colonial morphology, suggested that it may represent a selective advantage against antibiotics in an Achromobacter persisting population and potentially compromise the antibiotic management of CF airway infections., (Copyright © 2016 American Society for Microbiology.)

Achromobacter species are being increasingly isolated from the respiratory tract of cystic fibrosis patients. Recent reports indicate that Achromobacter ruhlandii is a potential human pathogen in cystic fibrosis-related infections. Here we report the draft genome of four A. ruhlandii strains isolated from cystic fibrosis patients in Brazil. This report describes A. ruhlandii as a potential opportunistic pathogen in cystic fibrosis and provides a framework to for additional enquires into potential virulence factors and resistance mechanisms within this species.

Quinoline is a refractory organic compound in the treatment of coking wastewater. The isolation of high efficiency quinoline-degrading bacteria from activated sludge and the evaluation of their degradation characteristics in the presence of phenol or in the actual coking wastewater are important for the improvement of effluent quality. The novel bacterial strain Pseudomonas aeruginosa KDQ4 was isolated from a quinoline enrichment culture obtained from the activated sludge of a coking wastewater treatment plant. The optimum temperature and initial pH for quinoline degradation were 33-38°C and 8-9, respectively. KDQ4 completely degraded 400 mg/L of quinoline within 24 h and 800 mg/L of phenol within 30 h. In the dual-substrate system, the removal efficiencies of quinoline and phenol at the same initial concentration (200 mg/L) by KDQ4 were 89% and 100% within 24 h, respectively, indicating that KDQ4 could simultaneously and quickly degrade quinoline and phenol in a coexistence system. Moreover, KDQ4 was able to adapt to actual coking wastewater containing high quinoline and phenol concentrations and rapidly remove them. KDQ4 also exhibited heterotrophic nitrification and aerobic denitrification potential under aerobic conditions. These results suggested a potential bioaugmentation role for KDQ4 in the removal of nitrogen-heterocyclic compounds and phenolics from coking wastewater.

Two bacterial strains, Achromobacter sp. (ACH01) and Sphingomonas sp. (SPH01), were isolated from a heavily polycyclic aromatic hydrocarbon (PAH)-contaminated soil (5431.3 ± 102.3 ppm) for their capacity to use a mixture of anthracene, pyrene, phenanthrene and fluorene as sole carbon sources for growth and for the capacity to produce biosurfactants. The two strains were exploited for bioaugmentation in a biopile pilot plant to increase the bioavailability and the degradation of the residual PAH contamination (99.5 ± 7.1 ppm) reached after 9 months of treatment. The denaturing gel gradient electrophoresis (DGGE) profile of the microbial ecology of the soil during the experimentation showed that the bioaugmentation approach was successful in terms of permanence of the two strains in the soil in treatment. The bioaugmentation of the two bacterial isolates positively correlated with the PAH depletion that reached 7.9 ± 2 ppm value in 2 months of treatment. The PAH depletion was assessed by the loss of the phyto-genotoxicity of soil elutriates on the model plant Vicia faba L., toxicological assessment adopted also to determine the minimum length of the decontamination process for obtaining both the depletion of the PAH contamination and the detoxification of the soil at the end of the process. The intermediate phases of the bioremediation process were the most significant in terms of toxicity, inducing genotoxic effects and selective DNA fragmentation in the stem cell niche of the root tip. The selective DNA fragmentation can be related to the selective induction of cell death of mutant stem cells that can compromise offsprings.

A novel biphasic system containing mineral medium and sand coated with a biologically weathered creosote-PAH mixture was developed to specifically enrich the high molecular weight polycyclic aromatic hydrocarbon (HMW PAH)-degrading community from a creosote-polluted soil. This consortium (UBHP) removed 70% of the total HMW PAHs and their alkyl-derivatives in 12 weeks. Based on a combined culture-dependent/independent approach, including clone library analysis, detection of catabolic genes, metabolomic profiles, and characterization of bacterial isolates, 10 phylotypes corresponding to five major genera (Sphingobium, Sphingomonas, Achromobacter, Pseudomonas, and Mycobacterium) were pointed out as key players within the community. In response to exposure to different single PAHs, members of sphingomonads were associated to the utilization of phenanthrene, fluoranthene, benzo[a]anthracene, and chrysene, while the degradation of pyrene was mainly associated to low-abundance mycobacteria. In addition to them, a number of uncultured phylotypes were detected, being of special relevance a group of Gammaproteobacteria closely related to a group previously associated with pyrene degradation that were here related to benzo(a)anthracene degradation. The overall environmental relevance of these phylotypes was confirmed by pyrosequencing analysis of the microbial community shift in the creosote-polluted soil during a lab-scale biostimulation.

Molecular methodologies were used to identify 28 Achromobacter spp. from patients with cystic fibrosis (CF). Multilocus sequence typing (MLST) identified 17 Achromobacter xylosoxidans isolates (all bla(OXA-114) positive), nine Achromobacter ruhlandii isolates (all bla(OXA-114) positive), one Achromobacter dolens isolate, and one Achromobacter insuavis isolate. All less common species were misidentified as A. xylosoxidans by matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS). Chronic colonization by clonally related A. ruhlandii isolates was demonstrated.

MICs and biofilm inhibitory concentrations (BICs) were measured for 68 cystic fibrosis (CF) Achromobacter isolates for amikacin, aztreonam, colistin, levofloxacin, and tobramycin. With the exception of colistin and levofloxacin, the remaining antibiotics had MIC90s, BICs at which 50% of the isolates were susceptible (BIC50s), and BICs at which 90% of the isolates were susceptible (BIC90s) equal to or above the highest concentrations tested. In a biofilm model, tobramycin was able to significantly increase killing of bacterial cells compared to controls, for intermediate-resistant strains only, at concentrations of 1,000 and 2,000 μg/ml., (Copyright © 2015, American Society for Microbiology. All Rights Reserved.)

Dental care unit waterlines (DCUWs) consist of complex networks of thin tubes that facilitate the formation of microbial biofilms. Due to the predilection toward a wet environment, strong adhesion, biofilm formation, and resistance to biocides, Pseudomonas aeruginosa, a major human opportunistic pathogen, is adapted to DCUW colonization. Other nonfermentative Gram-negative bacilli, such as members of the genus Achromobacter, are emerging pathogens found in water networks. We reported the 6.5-year dynamics of bacterial contamination of waterlines in a dental health care center with 61 dental care units (DCUs) connected to the same water supply system. The conditions allowed the selection and the emergence of clones of Achromobacter sp. and P. aeruginosa characterized by multilocus sequence typing, multiplex repetitive elements-based PCR, and restriction fragment length polymorphism in pulsed-field gel electrophoresis, biofilm formation, and antimicrobial susceptibility. One clone of P. aeruginosa and 2 clones of Achromobacter sp. colonized successively all of the DCUWs: the last colonization by P. aeruginosa ST309 led to the closing of the dental care center. Successive dominance of species and clones was linked to biocide treatments. Achromobacter strains were weak biofilm producers compared to P. aeruginosa ST309, but the coculture of P. aeruginosa and Achromobacter enhanced P. aeruginosa ST309 biofilm formation. Intraclonal genomic microevolution was observed in the isolates of P. aeruginosa ST309 collected chronologically and in Achromobacter sp. clone A. The contamination control was achieved by a complete reorganization of the dental health care center by removing the connecting tubes between DCUs., (Copyright © 2015, American Society for Microbiology. All Rights Reserved.)

A bacterial strain W-1, isolated from rural domestic wastewater, can utilize the environmental hormone di-n-butyl phthalate (DBP) as the sole carbon and energy source. The isolated bacterium species was confirmed to belong to the genus Achromobacter based on its 16S rRNA gene sequence. The results of substrate utilization tests showed that the strain W-1 could utilize other common phthalates and phenol. High-performance liquid chromatography analysis revealed that the optimal conditions for DBP degradation were pH 7.0, 35 °C, and an agitation rate of 175 rpm. Under these conditions, 500 mg/L of DBP was completely degraded within 30 h. The effects of heavy metals (50 mg/L Cu(2+) and 500 mg/L Pb(2+)) and surfactants (100 mg/L SDS and 500 mg/L Tween 20) on DBP degradation were investigated. The results demonstrated that Cu(2+) and SDS severely inhibited DBP degradation and Pb(2+) weakly inhibited DBP degradation, while Tween 20 greatly enhanced DBP degradation. Furthermore, phthalate degradation genes were found to be located on a plasmid present in Achromobacter sp. W-1.

In a previous study, three bacterial strains isolated from tropical hydrocarbon-contaminated soils and phylogenetically identified as Achromobacter sp. strain SL1, Pseudomonas sp. strain SL4 and Microbacterium esteraromaticum strain SL6 displayed angular dioxygenation and mineralization of carbazole in batch cultures. In this study, the ability of these isolates to survive and enhance carbazole degradation in soil were tested in field-moist microcosms. Strain SL4 had the highest survival rate (1.8 x 107 cfu/g) after 30 days of incubation in sterilized soil, while there was a decrease in population density in native (unsterilized) soil when compared with the initial population. Gas chromatographic analysis after 30 days of incubation showed that in sterilized soil amended with carbazole (100 mg/kg), 66.96, 82.15 and 68.54% were degraded by strains SL1, SL4 and SL6, respectively, with rates of degradation of 0.093, 0.114 and 0.095 mg kg-1 h-1. The combination of the three isolates as inoculum in sterilized soil degraded 87.13% carbazole at a rate of 0.121 mg kg-1 h-1. In native soil amended with carbazole (100 mg/kg), 91.64, 87.29 and 89.13% were degraded by strains SL1, SL4 and SL6 after 30 days of incubation, with rates of degradation of 0.127, 0.121 and 0.124 mg kg-1 h-1, respectively. This study successfully established the survivability (> 106 cfu/g detected after 30 days) and carbazole-degrading ability of these bacterial strains in soil, and highlights the potential of these isolates as seed for the bioremediation of carbazole-impacted environments.

Achromobacter species are increasingly isolated from the respiratory tract of cystic fibrosis patients and often a chronic infection is established. How Achromobacter sp. adapts to the human host remains uncharacterised. By comparing longitudinally collected isolates of Achromobacter sp. isolated from five CF patients, we have investigated the within-host evolution of clonal lineages. The majority of identified mutations were isolate-specific suggesting co-evolution of several subpopulations from the original infecting isolate. The largest proportion of mutated genes were involved in the general metabolism of the bacterium, but genes involved in virulence and antimicrobial resistance were also affected. A number of virulence genes required for initiation of acute infection were selected against, e.g. genes of the type I and type III secretion systems and genes related to pilus and flagellum formation or function. Six antimicrobial resistance genes or their regulatory genes were mutated, including large deletions affecting the repressor genes of an RND-family efflux pump and a beta-lactamase. Convergent evolution was observed for five genes that were all implicated in bacterial virulence. Characterisation of genes involved in adaptation of Achromobacter to the human host is required for understanding the pathogen-host interaction and facilitate design of future therapeutic interventions.

Achromobacter spp. are increasingly identified in Cystic Fibrosis (CF) patients and their ability to persistently colonize the CF respiratory tract (CFRT) suggests that Achromobacter species possess adaptive characteristics. We studied genome dynamics in 118 isolates recovered from 13 patients with Achromobacter chronic colonization (5-26 isolates per patient recovered over 13-61 months). Isolates were identified to species level by nrdA gene sequencing, subjected to Pulsed-Field Gel Electrophoresis (PFGE) and multiplex rep-PCR (MR-PCR), and rrs intragenomic diversity was studied by PCR-Temporal Temperature Gel Electrophoresis (TTGE). Intrapatient diversity was assessed: (i) from dynamics of XbaI and/or SpeI-based pulsotypes, (ii) from comparison of MR-PCR profiles, and (iii) by longitudinal analysis of rrs intragenomic diversity. Patients were chronically colonized by Achromobacter xylosoxidans (n=10), Achromobacter dolens (n=1) or Achromobacter insuavis (n=2). All strains displayed genomic diversification over time but A. insuavis showed higher pulsotype diversity compared to other species. Intragenomic rrs heterogeneity was found in strains from 6 of 13 patients and may be persistently observed. Achromobacter genome evolution observed during chronic colonization of the CFRT warrants further investigation of the adaptation features of the different species, as well as of the selective forces driving this adaptation in the CFRT., (Copyright © 2015 Elsevier B.V. All rights reserved.)

In this study, two pure strains, named HBCD-1 and HBCD-2, were isolated from a continuous anaerobic reactor over 300-days acclimation, which processed high capability of biodegrading Hexabromocyclododecane. Both of the two strains degraded HBCD diastereomers in different extents, especially strain HBCD-1, which interestingly degraded α-HBCD effectively. All of the degrading results were well fitted with the first-order kinetics model. By morphological observation and 16S rRNA gene sequence analysis, the strain HBCD-1 showed highest similarity with Achromobacter sp. Under the optimal culturing conditions of 30°C, pH 7 and the initial HBCD concentration of 500μg/L, the biodegradation rate of HBCD-1 reached 90% after 8days treatment. Moreover, during the biodegradation process by HBCD-1 strain, the concentration of bromide ion was lower than the theoretical value. Finally, 4 metabolites were determined by liquid chromatography-tandem mass spectrometry (LC-MS/MS), as well as a biodegradation pathway was proposed., (Copyright © 2015 Elsevier Ltd. All rights reserved.)

Background: Achromobacter spp. are Gram-negative bacilli from aqueous environments, occasionally involved in bacteraemia in immunocompromised hosts and in outbreaks., Aim: We describe the characteristics of an achromobacter bacteraemia outbreak in a paediatric onco-haematology department., Methods: Throughout a one-year period, 16 blood cultures from seven patients were positive for Achromobacter sp. All patients were immunocompromised, febrile, and central venous catheter (CVC) holders. A microbiological study was performed in patients' rooms, completed with an analysis of the disinfectant atomizers (didecyl diammonium chloride 0.25%, Surfanios, DMA). In total, 41 clinical and environmental strains were analysed by enterobacterial repetitive intergenic consensus (ERIC) polymerase chain reaction (PCR), repetitive PCR, and random amplified polymorphic DNA (RAPD)-PCR, and pulsed-field gel electrophoresis (PFGE). The bactericidal activity of DMA was studied on two Achromobacter sp. representative strains and one Pseudomonas aeruginosa reference strain, comparing biofilm and planktonic growth models., Findings: The seven patients, including two severe cases, were successfully treated by systemic antimicrobial therapy and/or catheter removal. The 25 environmental isolates were recovered with the following chronology: hospital filtered tap water, disinfectant atomizers, and patients' rooms. All environmental, patient, and atomizer strains had identical PCR and PFGE patterns. The disinfectant susceptibility assay revealed that the strain isolated from the atomizers had high survival abilities in biofilm conditions and remained resistant to DMA after short contact periods., Conclusion: The use of disinfectant atomizers associated with the survival of Achromobacter in the atomizer pipes may explain the contamination and colonization of the CVC. Control measures (non-atomizer containers and use of sterile water) allowed the eradication of the source and the outbreak control., (Copyright © 2014. Published by Elsevier Ltd.)