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1. Rapid evolution of an adaptive multicellular morphology of Candida auris during systemic infection

Author

Bing, Jian, Guan, Zhangyue, Zheng, Tianhong, Ennis, Craig L, Nobile, Clarissa J, Chen, Changbin, Chu, Haiqing, and Huang, Guanghua

Subjects
Microbiology, Biological Sciences, Biomedical and Clinical Sciences, Infectious Diseases, Genetics, Biotechnology, Aetiology, 2.1 Biological and endogenous factors, Infection, Good Health and Well Being, Animals, Mice, Candida, Candidiasis, Candida auris, Saccharomyces cerevisiae, Phenotype, Sepsis, Antifungal Agents, Microbial Sensitivity Tests, Mammals
Abstract

Candida auris has become a serious threat to public health. The mechanisms of how this fungal pathogen adapts to the mammalian host are poorly understood. Here we report the rapid evolution of an adaptive C. auris multicellular aggregative morphology in the murine host during systemic infection. C. auris aggregative cells accumulate in the brain and exhibit obvious advantages over the single-celled yeast-form cells during systemic infection. Genetic mutations, specifically de novo point mutations in genes associated with cell division or budding processes, underlie the rapid evolution of this aggregative phenotype. Most mutated C. auris genes are associated with the regulation of cell wall integrity, cytokinesis, cytoskeletal properties, and cellular polarization. Moreover, the multicellular aggregates are notably more recalcitrant to the host antimicrobial peptides LL-37 and PACAP relative to the single-celled yeast-form cells. Overall, to survive in the host, C. auris can rapidly evolve a multicellular aggregative morphology via genetic mutations.

Published
2024

12. Zinc Chelator N,N,N′,N′-Tetrakis(2-Pyridylmethyl)Ethylenediamine Reduces the Resistance of Mycobacterium abscessus to Imipenem

Author

He,Siyuan, Zou,Yuzhen, Zhan,Mengling, Guo,Qi, Zhang,Yongjie, Zhang,Zhemin, Li,Bing, Zhang,Shaoyan, and Chu,Haiqing

Subjects
Infection and Drug Resistance, polycyclic compounds, biochemical phenomena, metabolism, and nutrition, bacterial infections and mycoses
Abstract

Siyuan He,1,2,* Yuzhen Zou,1,2,* Mengling Zhan,1,2,* Qi Guo,1,2 Yongjie Zhang,1,2 Zhemin Zhang,1 Bing Li,1 Shaoyan Zhang,1 Haiqing Chu1,3 1Department of Respiratory Medicine, Shanghai Pulmonary Hospital, Tongji University School of Medicine, Shanghai 200433, People’s Republic of China; 2Tongji University School of Medicine, Shanghai 200092, People’s Republic of China; 3Shanghai Key Laboratory of Tuberculosis, Shanghai Pulmonary Hospital, Tongji University School of Medicine, Shanghai 200433, People’s Republic of China*These authors contributed equally to this workCorrespondence: Haiqing Chu; Shaoyan ZhangDepartment of Respiratory Medicine, Shanghai Pulmonary Hospital, Tongji University School of Medicine, No. 507 Zhengmin Road, Shanghai 200433, People’s Republic of ChinaTel/ Fax +86 21 6511 5006Email chu_haiqing@126.com; zhangshaoyan000@163.comPurpose: Imipenem is one of the very few effective options for treating Mycobacterium abscessus (M. abscessus) infections; the development of imipenem resistance is a major health concern.Materials and Methods: The susceptibility of 194 clinical M. abscessus isolates to imipenem was determined. The ability of imipenem to synergize with N,N,N′,N′-tetrakis(2-pyridylmethyl)ethylenediamine (TPEN), a zinc chelator and a metallo-β-lactamases (MBLs) inhibitor, to inhibit M. abscessus growth was also assessed.Results: M. abscessus exhibited an elevated resistance to imipenem (MIC50 = 16 mg/L, MIC90 = 64 mg/L). A combination of TPEN and imipenem synergized to inhibit the growth of 100% of imipenem-resistant and 79.2% of imipenem-resistance intermediate isolates; no synergy was observed treating imipenem-sensitive isolates. A remarkable decrease in the MIC50 (from 16 to 4 mg/L) and MIC90 (from 64 to 8 mg/L) of imipenem was observed when it was combined with TPEN; the portion of imipenem-resistant isolates also decreased (from 48.4% to 0%). Consistent with these results demonstrating synergy, a time-kill assay showed the addition of TPEN significantly improved the bactericidal activity of imipenem toward M. abscessus. Similarly, EDTA (a potent MBLs inhibitor) promoted the anti-M. abscessus activity of imipenem in a disk assay, corroborating the effect of TPEN and supporting the role of MBLs in imipenem resistance exhibited by some isolates.Conclusion: These findings demonstrate that TPEN can reduce the resistance of M. abscessus to imipenem and suggest that the inhibition of MBLs activity is the underlying mechanism.Keywords: Mycobacterium abscessus, TPEN, imipenem resistance, metallo-β-lactamases

Published
2020

13. Efflux Pumps Contribute to Intrinsic Clarithromycin Resistance in Clinical, Mycobacterium abscessus Isolates

Author

Guo, Qi, Chen, Jianhui, Zhang, Shaoyan, Zou, Yuzhen, Zhang, Yongjie, Huang, Dongdong, Zhang, Zhemin, Li, Bing, and Chu, Haiqing

Subjects
Mycobacterium abscessus, Infection and Drug Resistance, efflux pumps, clarithromycin resistance, bacterial infections and mycoses, Original Research
Abstract

Qi Guo,1,2 Jianhui Chen,1,2 Shaoyan Zhang,1 Yuzhen Zou,1,2 Yongjie Zhang,1,2 Dongdong Huang,1 Zhemin Zhang,1 Bing Li,1 Haiqing Chu1,3 1Department of Respiratory Medicine, Shanghai Pulmonary Hospital, Tongji University School of Medicine, Shanghai 200433, People’s Republic of China; 2Tongji University School of Medicine, Shanghai 200092, People’s Republic of China; 3Shanghai Key Laboratory of Tuberculosis, Shanghai Pulmonary Hospital, Tongji University School of Medicine, Shanghai 200433, People’s Republic of ChinaCorrespondence: Haiqing Chu; Bing LiDepartment of Respiratory Medicine, Shanghai Pulmonary Hospital, Tongji University School of Medicine, No. 507 Zhengmin Road, Shanghai 200433, People’s Republic of ChinaTel/Fax +86 021 6511 5006Email chu_haiqing@126.com; libing044162@163.comPurpose: The emergence of clarithromycin resistance is a challenge in treating Mycobacterium abscessus infections. Known mechanisms that contribute to intrinsic clarithromycin resistance focus on rrl gene-related mutations, but resistant clinical isolates often exhibit an inconsistent rrl genotype.Patients and Methods: In this study, 194 clinical Mycobacterium abscessus isolates were collected from patients with lung infections and the whole genome of each isolate was sequenced. A comprehensive examination of the molecular mechanisms underlying intrinsic clarithromycin resistance was performed, combining MIC determination, comparative genome sequence analysis and qRT-PCR.Results: Of the 194 isolates, 13 (6.7%) were clarithromycin resistant; only seven of these harbored a rrl 2270/2271 mutation. The remaining six resistant isolates did not exhibit a specific resistance-associated mutation in the clarithromycin target-site genes, rrl, rplC, rplD and rplV, or in the rrl modification gene erm(41). qRT-PCR analysis showed that the increased expression of the efflux pump genes, MAB_2355c, MAB_1409c and MAB_1846, as well as their positive regulatory gene whiB7, consistently correlated with increased clarithromycin resistance. The presence of efflux pump inhibitors significantly decreased the MIC of clarithromycin for nonsusceptible isolates, especially the intrinsic resistant isolates that exhibited no rrl 2270/2271 mutation.Conclusion: These findings indicate that efflux pumps play a prominent role in the intrinsic resistance of M. abscessus to clarithromycin, complementing other known resistance mechanisms.Keywords: Mycobacterium abscessus, clarithromycin resistance, efflux pumps

Published
2020

14. Efflux Pumps Contribute to Intrinsic Clarithromycin Resistance in Clinical, Mycobacterium abscessus Isolates

Author

Guo,Qi, Chen,Jianhui, Zhang,Shaoyan, Zou,Yuzhen, Zhang,Yongjie, Huang,Dongdong, Zhang,Zhemin, Li,Bing, Chu,Haiqing, Guo,Qi, Chen,Jianhui, Zhang,Shaoyan, Zou,Yuzhen, Zhang,Yongjie, Huang,Dongdong, Zhang,Zhemin, Li,Bing, and Chu,Haiqing

Abstract

Qi Guo,1,2 Jianhui Chen,1,2 Shaoyan Zhang,1 Yuzhen Zou,1,2 Yongjie Zhang,1,2 Dongdong Huang,1 Zhemin Zhang,1 Bing Li,1 Haiqing Chu1,3 1Department of Respiratory Medicine, Shanghai Pulmonary Hospital, Tongji University School of Medicine, Shanghai 200433, People’s Republic of China; 2Tongji University School of Medicine, Shanghai 200092, People’s Republic of China; 3Shanghai Key Laboratory of Tuberculosis, Shanghai Pulmonary Hospital, Tongji University School of Medicine, Shanghai 200433, People’s Republic of ChinaCorrespondence: Haiqing Chu; Bing LiDepartment of Respiratory Medicine, Shanghai Pulmonary Hospital, Tongji University School of Medicine, No. 507 Zhengmin Road, Shanghai 200433, People’s Republic of ChinaTel/Fax +86 021 6511 5006Email chu_haiqing@126.com; libing044162@163.comPurpose: The emergence of clarithromycin resistance is a challenge in treating Mycobacterium abscessus infections. Known mechanisms that contribute to intrinsic clarithromycin resistance focus on rrl gene-related mutations, but resistant clinical isolates often exhibit an inconsistent rrl genotype.Patients and Methods: In this study, 194 clinical Mycobacterium abscessus isolates were collected from patients with lung infections and the whole genome of each isolate was sequenced. A comprehensive examination of the molecular mechanisms underlying intrinsic clarithromycin resistance was performed, combining MIC determination, comparative genome sequence analysis and qRT-PCR.Results: Of the 194 isolates, 13 (6.7%) were clarithromycin resistant; only seven of these harbored a rrl 2270/2271 mutation. The remaining six resistant isolates did not exhibit a specific resistance-associated mutation in the clarithromycin target-site genes, rrl, rplC, rplD and rplV, or in the rrl modification gene erm(41). qRT-PCR analysis showed that the increased expression of the efflux pump genes, MAB_2355c, MAB_1409c and MAB_1846, as well as their positive regulatory gen

Published
2020

21. Prevalence of nontuberculous mycobacteria in patients with bronchiectasis: a meta-analysis

Author

Chu, Haiqing, Zhao, Lan, Xiao, Heping, Zhang, Zhemin, Zhang, Jinbo, Gui, Tao, Gong, Sugang, Xu, Liyun, and Sun, Xiwen

Subjects
nontuberculous mycobacteria, meta-analysis, Systematic review/Meta-analysis, bronchiectasis, prevalence, bacterial infections and mycoses
Abstract

Introduction Nontuberculous mycobacteria (NTM) have emerged as critical opportunistic pathogens of lung diseases recently. Patients with preexisting bronchiectasis are susceptible to NTM. Nevertheless, patients with preexisting bronchiectasis are susceptible to NTM but the prevalence of NTM pulmonary infection in different species and geographical areas is still not fully understood. Material and methods The relevant data of the prevalence of NTM in patients with bronchiectasis were retrieved by searching the main databases such as PubMed, MEDLINE, Cochrane Library, and EMBASE. This meta-analysis was performed using Rev. Man 5.1 and Stata 11.0 software. The collected information of NTM prevalence was chosen as the effect size. Results The results of the meta-analysis showed that the overall prevalence of NTM was 9.3% in patients with bronchiectasis. The further stratification of subgroup analysis indicated that the combined prevalence of NTM was higher in studies whose “sample size” was more than or equal to 100 (p = 0.002), in studies in which “time of study” was after or equal to 2002 (p < 0.001), in studies in which “participants’ geographic location” was Asian (p < 0.001) and in studies whose “method of study” was retrospective (p = 0.002) as well, compared with corresponding groups. Conclusions Our findings suggested that the prevalence NTM infection is high in patients with bronchiectasis. A larger number of definitive randomized trials are still required to assess this research issue.

Published
2014

25. Clinical characteristics of amyloidosis with isolated respiratory system involvement: a review of 13 cases

Author

Chu, Haiqing, Zhao, Lan, Zhang, Zhemin, Gui, Tao, Yi, Xianghua, and Sun, Xiwen

Subjects
Lung diseases -- Care and treatment -- Patient outcomes -- Demographic aspects -- Research, Amyloidosis -- Care and treatment -- Patient outcomes -- Demographic aspects -- Research, Health
Abstract

Byline: Haiqing. Chu, Lan. Zhao, Zhemin. Zhang, Tao. Gui, Xianghua. Yi, Xiwen. Sun Background: Isolated pulmonary amyloidosis is a very rare disease. Methods: We retrospectively reviewed the records of patients [...]

Published
2012

26. Characterization of Mycobacterium Abscessus Subtypes in Shanghai of China

Author

Luo, Liulin, Li, Bing, Chu, Haiqing, Huang, Dongdong, Zhang, Zhemin, Zhang, Jingbo, Gui, Tao, Xu, Liyun, Zhao, Lan, Sun, Xiwen, and Xiao, Heping

Subjects
Male, China, Mycobacterium Infections, Nontuberculous, Nontuberculous Mycobacteria, Clinical Trial/Experimental Study, Microbial Sensitivity Tests, Middle Aged, bacterial infections and mycoses, Anti-Bacterial Agents, Bacterial Typing Techniques, Electrophoresis, Gel, Pulsed-Field, Pneumonia, Bacterial, DNA Barcoding, Taxonomic, Humans, Female, Tomography, X-Ray Computed, Research Article, Multilocus Sequence Typing, Retrospective Studies
Abstract

The aim of the study was to investigate the epidemic characteristics of Mycobacterium abscessus in Shanghai. Fifty-five strains from 55 M. abscessus pulmonary disease patients were isolated. Drug sensitivity was measured by a broth microdilution method. Subtypes of M. abscessus were identified by DNA sequencing. Multilocus sequence typing (MLST), mining spanning tree (MST), and pulsed-field gel electrophoresis (PFGE) were used to analyze sequence types (ST) and clonal complexes (CC). Clinical manifestations were assessed by CT imaging. We identified 42 A isolates, 11 M, and 2 B-subtypes. A and M were highly sensitive to tigecycline and amikacin (97.6–100%). The A-type easily developed drug resistance against clarithromycin. Both types were highly resistance to sulfonamides, moxifloxacin, doxycycline, imipenem, and tobramycin. MLST analysis identified 41 STs including 32 new STs. The MST algorithm distributed 55 isolates into 12 separate CC. The PFGE analysis exhibited 53 distinct restriction patterns and the M-type was closely clustered according to their ST and CC numbers. CT imaging showed that tree-in-bud and patch shadow were commonly observed in M-type, whereas pulmonary cavities were often found in A-type infection patients (P

Published
2016

30. Evaluation of Matrix-Assisted Laser Desorption Ionization−Time of Flight Mass Spectrometry for Identification of Mycobacterium abscessus Subspecies According to Whole-Genome Sequencing

Author

Luo, Liulin, primary, Liu, Weijia, additional, Li, Bing, additional, Li, Mengling, additional, Huang, Dongdong, additional, Jing, Linjie, additional, Chen, Huiping, additional, Yang, Jinghui, additional, Yue, Jun, additional, Wang, Fang, additional, Chu, Haiqing, additional, and Zhang, Zhemin, additional

Published
2016
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36. Evaluation of Matrix-Assisted Laser Desorption Ionization-Time of Flight Mass Spectrometry for Identification of Mycobacterium abscessusSubspecies According to Whole-Genome Sequencing

Author

Luo, Liulin, Liu, Weijia, Li, Bing, Li, Mengling, Huang, Dongdong, Jing, Linjie, Chen, Huiping, Yang, Jinghui, Yue, Jun, Wang, Fang, Chu, Haiqing, and Zhang, Zhemin

Abstract

ABSTRACTThis study was undertaken to evaluate the utility of matrix-assisted laser desorption ionization–time of flight mass spectrometry with the Vitek MS Plus system for identifying Mycobacterium abscessussubspecies in order to facilitate more rapid and appropriate therapy. A total of 175 clinical M. abscessusstrains were identified by whole-genome sequencing analysis: 139 Mycobacterium abscessussubsp. abscessusand 36 Mycobacterium abscessussubsp. massiliense. The research-use-only (RUO) Saramis Knowledge Base database v.4.12 was modified accordingly by adding 40 M. abscessussubsp. abscessusand 19 M. abscessussubsp. massiliensereference spectra to construct subspecies SuperSpectra. A blind test, used to validate the remaining 116 isolates, yielded 99.1% (n= 115) reliability and only 0.9% (n= 1) error for subspecies identification. Among the two subspecies SuperSpectra, two specific peaks were found for M. abscessussubsp. abscessusand four specific peaks were found for M. abscessussubsp. massiliense. Our study is the first to report differential peaks 3,354.4 m/zand 6,711.1 m/z, which were specific for M. abscessussubsp. massiliense. Our research demonstrates the capacity of the Vitek MS RUO Saramis Knowledge Base database to identify M. abscessusat the subspecies level. Moreover, it validates the potential ease and accuracy with which it can be incorporated into the IVD system for the identification of M. abscessussubspecies.

Published
2016
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39. The Clarithromycin Susceptibility Genotype Affects the Treatment Outcome of Patients with Mycobacterium abscessusLung Disease

Author

Guo, Qi, Chu, Haiqing, Ye, Meiping, Zhang, Zhemin, Li, Bing, Yang, Shiyi, Ma, Wei, and Yu, Fangyou

Abstract

ABSTRACTMycobacterium abscessusaccounts for a large proportion of lung disease cases caused by rapidly growing mycobacteria. The association between clarithromycin sensitivity and treatment outcome is clear. However, M. abscessusculture and antibiotic susceptibility testing are time-consuming. Clarithromycin susceptibility genotyping offers an alternate, rapid approach to predicting the efficacy of clarithromycin-based antibiotic therapy. M. abscessuslung disease patients were divided into two groups based upon the clarithromycin susceptibility genotype of the organism isolated. A retrospective analysis was conducted to compare the clinical features, microbiological characteristics, and treatment outcomes of the two groups. Several other potential predictors of the response to treatment were also assessed. Sixty-nine patients were enrolled in the clarithromycin-resistant genotype group, which included 5 infected with rrl2058-2059 mutants and 64 infected with erm(41)T28-type M. abscessus; 31 were in the clarithromycin-sensitive group, i.e., 6 and 25 patients infected with genotypes erm(41)C28 and erm(41) M type, respectively. The results showed that lung disease patients infected with clarithromycin-sensitive and -resistant M. abscessusgenotypes differed significantly in clarithromycin-based combination treatment outcomes. Patients infected with the clarithromycin-sensitive genotype exhibited higher initial and final sputum-negative conversion and radiological improvement rates and better therapeutic outcomes. Multivariate analysis demonstrated that genotyping was a reliable and, more importantly, rapid means of predicting the efficacy of clarithromycin-based antibiotic treatment for M. abscessuslung disease.

Published
2018
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41. Biology and genetic diversity of <italic>Candida krusei</italic> isolates from fermented vegetables and clinical samples in China.

Author

Zheng, Tianhong, Ji, Lingyu, Chen, Yi, Cao, Chengjun, Bing, Jian, Hu, Tianren, Zheng, Qiushi, Wu, Dan, Chu, Haiqing, and Huang, Guanghua

Subjects
*WHOLE genome sequencing, *POPULATION genetics, *COLONIZATION (Ecology), *AMPHOTERICIN B, *GENETIC variation
Abstract

Candida krusei, also known as Pichia kudriavzevii, is an emerging non-albicans Candida (NAC) species causing both superficial and deep-seated infections in humans. This fungal pathogen is inherently resistant to the first-line antifungal drug, fluconazole, and is widely distributed in natural environments such as soil, foods, vegetables, and fruits. In this study, we collected 86 C. krusei strains from clinical settings and traditional fermented vegetables from different areas of China. Compared to C. krusei strains from fermented vegetables, clinical isolates exhibited a higher ability to undergo filamentation and biofilm development, which could facilitate its host colonization and infections. Isolates from fermented vegetables showed higher resistance to several antifungal drugs including fluconazole, voriconazole, itraconazole, amphotericin B, and caspofungin, than clinical strains, while they were more susceptible to posaconazole than clinical strains. Although C. krusei has been thought to be a diploid organism, we found that one-fourth of clinical strains and the majority of isolates from fermented vegetables (87.5%) are triploid. Whole-genome sequencing and population genetic analyses demonstrated that isolates from clinical settings and fermented food are genetically associated, and distributed across a wide range of genetic clusters. Additionally, we found that six nucleotide substitutions at the promoter region of the ABC11 gene, encoding a multidrug efflux pump, could play a critical role in antifungal resistance in this species. Given the ubiquitous distribution of C. krusei strains in fermented vegetables and their genetic association with clinical strains, a One Health approach will be necessary to control the prevalence of this pathogen. [ABSTRACT FROM AUTHOR]

Published
2024
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42. Evaluation of Matrix-Assisted Laser Desorption Ionization-Time of Flight Mass Spectrometry for Identification of Mycobacterium abscessus Subspecies According to Whole-Genome Sequencing.

Author

Luo L, Liu W, Li B, Li M, Huang D, Jing L, Chen H, Yang J, Yue J, Wang F, Chu H, and Zhang Z

Subjects
Base Sequence, DNA, Bacterial genetics, Databases, Factual, Genome, Bacterial genetics, Humans, Mycobacterium Infections, Nontuberculous microbiology, Sequence Analysis, DNA, Bacterial Typing Techniques methods, Mycobacterium Infections, Nontuberculous diagnosis, Nontuberculous Mycobacteria classification, Nontuberculous Mycobacteria isolation & purification, Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization methods
Abstract

This study was undertaken to evaluate the utility of matrix-assisted laser desorption ionization-time of flight mass spectrometry with the Vitek MS Plus system for identifying Mycobacterium abscessus subspecies in order to facilitate more rapid and appropriate therapy. A total of 175 clinical M. abscessus strains were identified by whole-genome sequencing analysis: 139 Mycobacterium abscessus subsp. abscessus and 36 Mycobacterium abscessus subsp. massiliense The research-use-only (RUO) Saramis Knowledge Base database v.4.12 was modified accordingly by adding 40 M. abscessus subsp. abscessus and 19 M. abscessus subsp. massiliense reference spectra to construct subspecies SuperSpectra. A blind test, used to validate the remaining 116 isolates, yielded 99.1% (n = 115) reliability and only 0.9% (n = 1) error for subspecies identification. Among the two subspecies SuperSpectra, two specific peaks were found for M. abscessus subsp. abscessus and four specific peaks were found for M. abscessus subsp. massiliense Our study is the first to report differential peaks 3,354.4 m/z and 6,711.1 m/z, which were specific for M. abscessus subsp. massiliense Our research demonstrates the capacity of the Vitek MS RUO Saramis Knowledge Base database to identify M. abscessus at the subspecies level. Moreover, it validates the potential ease and accuracy with which it can be incorporated into the IVD system for the identification of M. abscessus subspecies., (Copyright © 2016, American Society for Microbiology. All Rights Reserved.)

Published
2016
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