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Giovagnorio F, De Vito A, Madeddu G, Parisi SG, Geremia N. Resistance in Pseudomonas aeruginosa: A Narrative Review of Antibiogram Interpretation and Emerging Treatments. Antibiotics (Basel) 2023; 12:1621. [PMID: 37998823 PMCID: PMC10669487 DOI: 10.3390/antibiotics12111621] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2023] [Revised: 11/02/2023] [Accepted: 11/10/2023] [Indexed: 11/25/2023] Open
Abstract
Pseudomonas aeruginosa is a ubiquitous Gram-negative bacterium renowned for its resilience and adaptability across diverse environments, including clinical settings, where it emerges as a formidable pathogen. Notorious for causing nosocomial infections, P. aeruginosa presents a significant challenge due to its intrinsic and acquired resistance mechanisms. This comprehensive review aims to delve into the intricate resistance mechanisms employed by P. aeruginosa and to discern how these mechanisms can be inferred by analyzing sensitivity patterns displayed in antibiograms, emphasizing the complexities encountered in clinical management. Traditional monotherapies are increasingly overshadowed by the emergence of multidrug-resistant strains, necessitating a paradigm shift towards innovative combination therapies and the exploration of novel antibiotics. The review accentuates the critical role of accurate antibiogram interpretation in guiding judicious antibiotic use, optimizing therapeutic outcomes, and mitigating the propagation of antibiotic resistance. Misinterpretations, it cautions, can inadvertently foster resistance, jeopardizing patient health and amplifying global antibiotic resistance challenges. This paper advocates for enhanced clinician proficiency in interpreting antibiograms, facilitating informed and strategic antibiotic deployment, thereby improving patient prognosis and contributing to global antibiotic stewardship efforts.
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Affiliation(s)
- Federico Giovagnorio
- Department of Molecular Medicine, University of Padua, 35121 Padua, Italy; (F.G.); (S.G.P.)
| | - Andrea De Vito
- Unit of Infectious Diseases, Department of Medicine, Surgery and Pharmacy, University of Sassari, 07100 Sassari, Italy;
| | - Giordano Madeddu
- Unit of Infectious Diseases, Department of Medicine, Surgery and Pharmacy, University of Sassari, 07100 Sassari, Italy;
| | | | - Nicholas Geremia
- Unit of Infectious Diseases, Department of Clinical Medicine, Ospedale “dell’Angelo”, 30174 Venice, Italy
- Unit of Infectious Diseases, Department of Clinical Medicine, Ospedale Civile “S.S. Giovanni e Paolo”, 30122 Venice, Italy
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Kauser A, Parisini E, Suarato G, Castagna R. Light-Based Anti-Biofilm and Antibacterial Strategies. Pharmaceutics 2023; 15:2106. [PMID: 37631320 PMCID: PMC10457815 DOI: 10.3390/pharmaceutics15082106] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2023] [Revised: 07/29/2023] [Accepted: 08/02/2023] [Indexed: 08/27/2023] Open
Abstract
Biofilm formation and antimicrobial resistance pose significant challenges not only in clinical settings (i.e., implant-associated infections, endocarditis, and urinary tract infections) but also in industrial settings and in the environment, where the spreading of antibiotic-resistant bacteria is on the rise. Indeed, developing effective strategies to prevent biofilm formation and treat infections will be one of the major global challenges in the next few years. As traditional pharmacological treatments are becoming inadequate to curb this problem, a constant commitment to the exploration of novel therapeutic strategies is necessary. Light-triggered therapies have emerged as promising alternatives to traditional approaches due to their non-invasive nature, precise spatial and temporal control, and potential multifunctional properties. Here, we provide a comprehensive overview of the different biofilm formation stages and the molecular mechanism of biofilm disruption, with a major focus on the quorum sensing machinery. Moreover, we highlight the principal guidelines for the development of light-responsive materials and photosensitive compounds. The synergistic effects of combining light-triggered therapies with conventional treatments are also discussed. Through elegant molecular and material design solutions, remarkable results have been achieved in the fight against biofilm formation and antibacterial resistance. However, further research and development in this field are essential to optimize therapeutic strategies and translate them into clinical and industrial applications, ultimately addressing the global challenges posed by biofilm and antimicrobial resistance.
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Affiliation(s)
- Ambreen Kauser
- Department of Biotechnology, Latvian Institute of Organic Synthesis, Aizkraukles 21, LV-1006 Riga, Latvia; (A.K.); (E.P.)
- Faculty of Materials Science and Applied Chemistry, Riga Technical University, Paula Valdena 3, LV-1048 Riga, Latvia
| | - Emilio Parisini
- Department of Biotechnology, Latvian Institute of Organic Synthesis, Aizkraukles 21, LV-1006 Riga, Latvia; (A.K.); (E.P.)
- Department of Chemistry “G. Ciamician”, University of Bologna, Via Selmi 2, 40126 Bologna, Italy
| | - Giulia Suarato
- Istituto di Elettronica e di Ingegneria dell’Informazione e delle Telecomunicazioni, Consiglio Nazionale delle Ricerche, CNR-IEIIT, Piazza Leonardo da Vinci 32, 20133 Milano, Italy
| | - Rossella Castagna
- Department of Biotechnology, Latvian Institute of Organic Synthesis, Aizkraukles 21, LV-1006 Riga, Latvia; (A.K.); (E.P.)
- Dipartimento di Chimica, Materiali e Ingegneria Chimica “G. Natta”, Politecnico di Milano, Piazza Leonardo da Vinci 32, 20133 Milano, Italy
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Kabic J, Fortunato G, Vaz-Moreira I, Kekic D, Jovicevic M, Pesovic J, Ranin L, Opavski N, Manaia CM, Gajic I. Dissemination of Metallo-β-Lactamase-Producing Pseudomonas aeruginosa in Serbian Hospital Settings: Expansion of ST235 and ST654 Clones. Int J Mol Sci 2023; 24:ijms24021519. [PMID: 36675030 PMCID: PMC9863560 DOI: 10.3390/ijms24021519] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2022] [Revised: 01/03/2023] [Accepted: 01/09/2023] [Indexed: 01/14/2023] Open
Abstract
This nationwide study aimed to investigate the molecular characteristics of metallo-β-lactamase (MBL)-producing Pseudomonas aeruginosa in Serbia, underlying resistance mechanisms, the genetic context of detected MBL genes, and the clonal relationship between isolates harboring genes-encoding MBL. Overall, 320/5334 isolates collected from 2018 to 2021 were identified as P. aeruginosa. Carbapenem-resistant P. aeruginosa (CRPA) were screened for the presence of blaVIM, blaIMP, and blaNDM, genes whereas MBL-positive isolates were tested for the presence of the blaCTX-M-2, blaPER, blaTEM, blaSHV, blaVEB, and blaGES. Multilocus sequence typing and phylogenomic analysis were performed for P. aeruginosa-producing MBL. The majority of the P. aeruginosa isolates were recovered from the lower respiratory tract (n = 120; 37.5%) and wound specimens (n = 108; 33.75%). CRPA isolates accounted for 43.1% (n = 138) of the tested isolates, 31 out of them being blaNDM-1-positive (22.5%). The colistin resistance rate was 0.3%. MLST analysis revealed the occurrence of ST235 (n = 25) and ST654 (n = 6), mostly confined to Serbia. The distribution of beta-lactamase-encoding genes in these isolates suggested clonal dissemination and possible recombination: ST235/blaNDM-1, ST235/blaNDM-1/blaPER-1, ST654/blaNDM-1, ST654/blaNDM-1/blaPER-1, and ST654/blaNDM-1/blaGES-5. High-risk clones ST235 and ST654 identified for the first time in Serbia, are important vectors of acquired MBL and ESBL and their associated multidrug resistance phenotypes represent a cause for considerable concern.
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Affiliation(s)
- Jovana Kabic
- Institute of Microbiology and Immunology, Faculty of Medicine, University of Belgrade, Dr Subotica Starijeg 1, 11000 Belgrade, Serbia
| | - Gianuario Fortunato
- CBQF—Centro de Biotecnologia e Química Fina—Laboratório Associado, Universidade Católica Portuguesa, Escola Superior de Biotecnologia, Rua Diogo Botelho 1327, 4169-005 Porto, Portugal
| | - Ivone Vaz-Moreira
- CBQF—Centro de Biotecnologia e Química Fina—Laboratório Associado, Universidade Católica Portuguesa, Escola Superior de Biotecnologia, Rua Diogo Botelho 1327, 4169-005 Porto, Portugal
| | - Dusan Kekic
- Institute of Microbiology and Immunology, Faculty of Medicine, University of Belgrade, Dr Subotica Starijeg 1, 11000 Belgrade, Serbia
| | - Milos Jovicevic
- Institute of Microbiology and Immunology, Faculty of Medicine, University of Belgrade, Dr Subotica Starijeg 1, 11000 Belgrade, Serbia
| | - Jovan Pesovic
- Faculty of Biology, University of Belgrade, Studentski trg 16, 11000 Belgrade, Serbia
| | - Lazar Ranin
- Institute of Microbiology and Immunology, Faculty of Medicine, University of Belgrade, Dr Subotica Starijeg 1, 11000 Belgrade, Serbia
| | - Natasa Opavski
- Institute of Microbiology and Immunology, Faculty of Medicine, University of Belgrade, Dr Subotica Starijeg 1, 11000 Belgrade, Serbia
| | - Célia M. Manaia
- CBQF—Centro de Biotecnologia e Química Fina—Laboratório Associado, Universidade Católica Portuguesa, Escola Superior de Biotecnologia, Rua Diogo Botelho 1327, 4169-005 Porto, Portugal
| | - Ina Gajic
- Institute of Microbiology and Immunology, Faculty of Medicine, University of Belgrade, Dr Subotica Starijeg 1, 11000 Belgrade, Serbia
- Correspondence: ; Tel.: +381-113643-3373
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Thacharodi A, Lamont IL. Aminoglycoside resistance in Pseudomonas aeruginosa: the contribution of the MexXY-OprM efflux pump varies between isolates. J Med Microbiol 2022; 71. [PMID: 35708991 DOI: 10.1099/jmm.0.001551] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Introduction. Aminoglycoside antibiotics are widely used to treat infections of Pseudomonas aeruginosa. The MexXY-OprM efflux pump is an important contributor to aminoglycoside tolerance in P. aeruginosa reference strains and expression of the mexXY genes is repressed by the MexZ repressor protein. Direct investigation of the role of this efflux pump in clinical isolates is relatively limited.Hypothesis. The contribution of MexXY-OprM to P. aeruginosa aminoglycoside resistance is isolate-specific.Aim. To quantify the role of MexXY-OprM and its repressor, MexZ, in clinical isolates of P. aeruginosa. Methodology. The mexXY genes were deleted from ten clinical isolates of P. aeruginosa, and the mexZ gene from nine isolates. Antimicrobial susceptibility testing was carried out for commonly used antipseudomonal drugs on the engineered mutants and the isogenic wild-type isolates. RT-qPCR was used to measure expression of the mexX gene.Results. All but one of the mexXY mutants were more susceptible to the clinically used aminoglycosides tobramycin, gentamicin and amikacin but the degree to which susceptibility increased varied greatly between isolates. The mexXY mutants were also more susceptible to a fluoroquinolone, ciprofloxacin. In three isolates with functional MexZ, deletion of mexZ increased expression of mexXY and aminoglycoside tolerance. Conversely, deleting mexZ from six clinical isolates with mexZ sequence variants had little or no effect on expression of mexXY or on aminoglycoside susceptibility, consistent with the variants abolishing MexZ function. Genome analysis showed that over 50 % of 619 clinical isolates had sequence variants predicted to reduce the affinity of MexZ for DNA, likely increasing mexXY expression and hence efflux of aminoglycosides.Conclusion. Our findings show that the interplay between MexXY, MexZ and the level of mexXY expression plays an important role in aminoglycoside resistance in clinical isolates of P. aeruginosa but the magnitude of the contribution of this efflux pump to resistance is isolate-specific.
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Affiliation(s)
- Aswin Thacharodi
- Department of Biochemistry, University of Otago, Dunedin, New Zealand
| | - Iain L Lamont
- Department of Biochemistry, University of Otago, Dunedin, New Zealand
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Glen KA, Lamont IL. β-lactam Resistance in Pseudomonas aeruginosa: Current Status, Future Prospects. Pathogens 2021; 10:1638. [PMID: 34959593 DOI: 10.3390/pathogens10121638] [Citation(s) in RCA: 38] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2021] [Revised: 12/06/2021] [Accepted: 12/16/2021] [Indexed: 12/12/2022] Open
Abstract
Pseudomonas aeruginosa is a major opportunistic pathogen, causing a wide range of acute and chronic infections. β-lactam antibiotics including penicillins, carbapenems, monobactams, and cephalosporins play a key role in the treatment of P. aeruginosa infections. However, a significant number of isolates of these bacteria are resistant to β-lactams, complicating treatment of infections and leading to worse outcomes for patients. In this review, we summarize studies demonstrating the health and economic impacts associated with β-lactam-resistant P. aeruginosa. We then describe how β-lactams bind to and inhibit P. aeruginosa penicillin-binding proteins that are required for synthesis and remodelling of peptidoglycan. Resistance to β-lactams is multifactorial and can involve changes to a key target protein, penicillin-binding protein 3, that is essential for cell division; reduced uptake or increased efflux of β-lactams; degradation of β-lactam antibiotics by increased expression or altered substrate specificity of an AmpC β-lactamase, or by the acquisition of β-lactamases through horizontal gene transfer; and changes to biofilm formation and metabolism. The current understanding of these mechanisms is discussed. Lastly, important knowledge gaps are identified, and possible strategies for enhancing the effectiveness of β-lactam antibiotics in treating P. aeruginosa infections are considered.
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Ahmed MS, Lauersen KJ, Ikram S, Li C. Efflux Transporters' Engineering and Their Application in Microbial Production of Heterologous Metabolites. ACS Synth Biol 2021; 10:646-669. [PMID: 33751883 DOI: 10.1021/acssynbio.0c00507] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Metabolic engineering of microbial hosts for the production of heterologous metabolites and biochemicals is an enabling technology to generate meaningful quantities of desired products that may be otherwise difficult to produce by traditional means. Heterologous metabolite production can be restricted by the accumulation of toxic products within the cell. Efflux transport proteins (transporters) provide a potential solution to facilitate the export of these products, mitigate toxic effects, and enhance production. Recent investigations using knockout lines, heterologous expression, and expression profiling of transporters have revealed candidates that can enhance the export of heterologous metabolites from microbial cell systems. Transporter engineering efforts have revealed that some exhibit flexible substrate specificity and may have broader application potentials. In this Review, the major superfamilies of efflux transporters, their mechanistic modes of action, selection of appropriate efflux transporters for desired compounds, and potential transporter engineering strategies are described for potential applications in enhancing engineered microbial metabolite production. Future studies in substrate recognition, heterologous expression, and combinatorial engineering of efflux transporters will assist efforts to enhance heterologous metabolite production in microbial hosts.
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Affiliation(s)
- Muhammad Saad Ahmed
- Institute for Synthetic Biosystem/Department of Biochemical Engineering, School of Chemistry and Chemical Engineering, Beijing Institute of Technology (BIT), Beijing 100081, P. R. China
- Department of Biological Sciences, National University of Medical Sciences (NUMS), Abid Majeed Road, The Mall, Rawalpindi 46000, Pakistan
| | - Kyle J. Lauersen
- Biological and Environmental Sciences and Engineering Division (BESE), King Abdullah University of Science and Technology (KAUST), Thuwal 23955, Kingdom of Saudi Arabia
| | - Sana Ikram
- Beijing Higher Institution Engineering Research Center for Food Additives and Ingredients, Beijing Technology & Business University (BTBU), Beijing 100048, P. R. China
| | - Chun Li
- Institute for Synthetic Biosystem/Department of Biochemical Engineering, School of Chemistry and Chemical Engineering, Beijing Institute of Technology (BIT), Beijing 100081, P. R. China
- SynBio Research Platform, Collaborative Innovation Center of Chemical Science and Engineering, Key Laboratory of Systems Bioengineering, Ministry of Education, School of Chemical Engineering and Technology, Tianjin University, Tianjin 300350, P. R. China
- Key Laboratory for Industrial Biocatalysis, Ministry of Education, Department of Chemical Engineering, Tsinghua University, Beijing 100084, P. R. China
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Elnasser Z, Elsamarneh R, Obeidat H, Amarin Z, Jaradat S, Kaplan N. In-vitro activity of tigecycline against multidrug-resistant Gram negative bacteria: The experience of a university hospital. J Infect Public Health 2021; 14:478-483. [PMID: 33743369 DOI: 10.1016/j.jiph.2020.12.013] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2020] [Revised: 12/05/2020] [Accepted: 12/08/2020] [Indexed: 01/04/2023] Open
Abstract
The emergence of multidrug-resistant Gram negative bacteria has given rise to significant therapeutic challenges. These pathogens may have developed resistance to tigecycline, which is an alternative antibiotic used empirically in the treatment of serious infections. The objectives of this study were to identify the in-vitro activity of tigecycline against multidrug-resistant Gram negative strains isolated from clinical specimens and their related genes, at a university hospital. For this, 150 clinical isolates of multidrug-resistant Gram negative cultures from various clinical specimens were collected. Bacterial isolates were cultured, identified and their antibiotic susceptibilities were determined. Polymerase chain reaction was performed to amplify AcrB, AmpC, RamR, MexR, AdeB, TetA genes. Results revealed that all isolates were multidrug-resistant. The resistance of isolates was 91.4% to aztreonam, 94.6% to piperacillin, 34% to imipenem, 38.7% to meropenem, 71.3% to levofloxacin, 97.3% to ceftriaxone, 94.7% to cefepime, 9.3% to colistin, 78% to tetracycline, 21.4% to tigecycline and 68% to trimethoprim. AcrB, AmpC, RamR, MexR, AdeB, TetA genes were present in multidrug-resistant Gram negative bacteria. AcrB, RamR, TetA genes were related to tigecycline resistance. It is concluded that infections caused by multidrug-resistant Gram negative bacteria occur at a high rate. Most isolates were multi drug resistant, with 21.4% being resistant to tigecycline.
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Affiliation(s)
- Z Elnasser
- Pathology and Microbiology Department, Jordan University of Science and Technology, Jordan.
| | - R Elsamarneh
- Medical Laboratory Sciences Department, Jordan University of Science and Technology, Jordan
| | - H Obeidat
- Medical Laboratory Sciences Department, Jordan University of Science and Technology, Jordan
| | - Z Amarin
- Department of Obstetrics and Gynecology, Jordan University of Science and Technology, Jordan
| | - S Jaradat
- Department of Biotechnology and Genetic Engineering, Jordan university of Science and Technology, Jordan
| | - N Kaplan
- Pathology and Microbiology Department, Jordan University of Science and Technology, Jordan
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Xu C, Wang D, Zhang X, Liu H, Zhu G, Wang T, Cheng Z, Wu W, Bai F, Jin Y. Mechanisms for Rapid Evolution of Carbapenem Resistance in a Clinical Isolate of Pseudomonas aeruginosa. Front Microbiol 2020; 11:1390. [PMID: 32636831 PMCID: PMC7318546 DOI: 10.3389/fmicb.2020.01390] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2020] [Accepted: 05/29/2020] [Indexed: 01/02/2023] Open
Abstract
Infections by Pseudomonas aeruginosa are difficult to cure due to its high intrinsic and acquired antibiotic resistance. Once colonized the human host, and thanks to antibiotic treatment pressure, P. aeruginosa usually acquires genetic mutations which provide bacteria with antibiotic resistance as well as ability to better adapt to the host environment. Deciphering the evolutionary traits may provide important insights into the development of effective combinatory antibiotic therapy to treat P. aeruginosa infections. In this study, we investigated the molecular mechanisms by which a clinical isolate (ISP50) yields a carbapenem-resistant derivative (IRP41). RNAseq and genomic DNA reference mapping were conducted to compare the transcriptional profiles and in vivo evolutionary trajectories between the two isolates. Our results demonstrated that oprD mutation together with ampC hyper-expression contributed to the increased resistance to carbapenem in the isolate IRP41. Furthermore, a ldcA (PA5198) gene, encoding murein tetrapeptide carboxypeptidase, has been demonstrated for the first time to negatively influence the ampC expression in P. aeruginosa.
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Affiliation(s)
- Congjuan Xu
- State Key Laboratory of Medicinal Chemical Biology, Key Laboratory of Molecular Microbiology and Technology of the Ministry of Education, Department of Microbiology, College of Life Sciences, Nankai University, Tianjin, China
| | - Dan Wang
- State Key Laboratory of Medicinal Chemical Biology, Key Laboratory of Molecular Microbiology and Technology of the Ministry of Education, Department of Microbiology, College of Life Sciences, Nankai University, Tianjin, China
| | - Xinxin Zhang
- State Key Laboratory of Medicinal Chemical Biology, Key Laboratory of Molecular Microbiology and Technology of the Ministry of Education, Department of Microbiology, College of Life Sciences, Nankai University, Tianjin, China
| | - Huimin Liu
- Tianjin Union Medical Center, Nankai University Affiliated Hospital, Tianjin, China
| | - Guangbo Zhu
- Tianjin Union Medical Center, Nankai University Affiliated Hospital, Tianjin, China
| | - Tong Wang
- Department of Stomatology, Tianjin First Central Hospital, Tianjin, China
| | - Zhihui Cheng
- State Key Laboratory of Medicinal Chemical Biology, Key Laboratory of Molecular Microbiology and Technology of the Ministry of Education, Department of Microbiology, College of Life Sciences, Nankai University, Tianjin, China
| | - Weihui Wu
- State Key Laboratory of Medicinal Chemical Biology, Key Laboratory of Molecular Microbiology and Technology of the Ministry of Education, Department of Microbiology, College of Life Sciences, Nankai University, Tianjin, China
| | - Fang Bai
- State Key Laboratory of Medicinal Chemical Biology, Key Laboratory of Molecular Microbiology and Technology of the Ministry of Education, Department of Microbiology, College of Life Sciences, Nankai University, Tianjin, China
| | - Yongxin Jin
- State Key Laboratory of Medicinal Chemical Biology, Key Laboratory of Molecular Microbiology and Technology of the Ministry of Education, Department of Microbiology, College of Life Sciences, Nankai University, Tianjin, China
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Colque CA, Albarracín Orio AG, Feliziani S, Marvig RL, Tobares AR, Johansen HK, Molin S, Smania AM. Hypermutator Pseudomonas aeruginosa Exploits Multiple Genetic Pathways To Develop Multidrug Resistance during Long-Term Infections in the Airways of Cystic Fibrosis Patients. Antimicrob Agents Chemother 2020; 64:e02142-19. [PMID: 32071060 DOI: 10.1128/AAC.02142-19] [Citation(s) in RCA: 40] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2019] [Accepted: 12/20/2019] [Indexed: 12/30/2022] Open
Abstract
Pseudomonas aeruginosa exploits intrinsic and acquired resistance mechanisms to resist almost every antibiotic used in chemotherapy. Antimicrobial resistance in P. aeruginosa isolates recovered from cystic fibrosis (CF) patients is further enhanced by the occurrence of hypermutator strains, a hallmark of chronic infections in CF patients. However, the within-patient genetic diversity of P. aeruginosa populations related to antibiotic resistance remains unexplored. Here, we show the evolution of the mutational resistome profile of a P. aeruginosa hypermutator lineage by performing longitudinal and transversal analyses of isolates collected from a CF patient throughout 20 years of chronic infection. Our results show the accumulation of thousands of mutations, with an overall evolutionary history characterized by purifying selection. However, mutations in antibiotic resistance genes appear to have been positively selected, driven by antibiotic treatment. Antibiotic resistance increased as infection progressed toward the establishment of a population constituted by genotypically diversified coexisting sublineages, all of which converged to multidrug resistance. These sublineages emerged by parallel evolution through distinct evolutionary pathways, which affected genes of the same functional categories. Interestingly, ampC and ftsI, encoding the β-lactamase and penicillin-binding protein 3, respectively, were found to be among the most frequently mutated genes. In fact, both genes were targeted by multiple independent mutational events, which led to a wide diversity of coexisting alleles underlying β-lactam resistance. Our findings indicate that hypermutators, apart from boosting antibiotic resistance evolution by simultaneously targeting several genes, favor the emergence of adaptive innovative alleles by clustering beneficial/compensatory mutations in the same gene, hence expanding P. aeruginosa strategies for persistence.
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Miryala SK, Anbarasu A, Ramaiah S. Systems biology studies in Pseudomonas aeruginosa PA01 to understand their role in biofilm formation and multidrug efflux pumps. Microb Pathog 2019; 136:103668. [DOI: 10.1016/j.micpath.2019.103668] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2019] [Revised: 04/24/2019] [Accepted: 08/12/2019] [Indexed: 11/29/2022]
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Chetri S, Bhowmik D, Paul D, Pandey P, Chanda DD, Chakravarty A, Bora D, Bhattacharjee A. AcrAB-TolC efflux pump system plays a role in carbapenem non-susceptibility in Escherichia coli. BMC Microbiol 2019; 19:210. [PMID: 31488061 PMCID: PMC6727511 DOI: 10.1186/s12866-019-1589-1] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2019] [Accepted: 08/29/2019] [Indexed: 11/21/2022] Open
Abstract
Background Efflux pump mediated antibiotic resistance is an unnoticed and undetected mechanism in clinical microbiology laboratory. RND efflux systems are known for aminoglycoside and tetracycline resistance whereas their role in carbapenem non-susceptibility is not established. The study was undertaken to investigate the role of efflux pump in providing resistance against carbapenems and their response against concentration gradient carbapenem stress on the transcriptional level of the AcrAB gene in the clinical isolates of Escherichia coli from a tertiary referral hospital of Northeast India. Results Out of 298 non-susceptible Escherichia coli isolates 98 isolates were found to have efflux pump mediated carbapenem non-susceptibility. Among them thirty-five were non carbapenemase producers and their expressional levels were verified using qRT-PCR under concentration gradient carbapenem stress. In this study, a strong correlation between ertapenem resistance and AcrA overexpression was observed which has not been reported previously. Further, it was observed that imipenem stress increased AcrB expression in Escherichia coli which holds the novelty of this study. Additionally, the transcription of AcrR was insistently increased which is much higher than the transcriptional level of AcrA under concentration gradient carbapenem stress condition. Conclusion The study established that AcrAB pump is a relevant antibiotic resistance determinant in bacterial pathogen, has an important role in developing resistance against carbapenem group of antibiotics. Electronic supplementary material The online version of this article (10.1186/s12866-019-1589-1) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Shiela Chetri
- Department of Microbiology, Assam University, Silchar, Assam, India
| | | | - Deepjyoti Paul
- Department of Microbiology, Assam University, Silchar, Assam, India
| | - Piyush Pandey
- Department of Microbiology, Assam University, Silchar, Assam, India
| | | | - Atanu Chakravarty
- Department of Microbiology, Silchar Medical College and Hospital, Silchar, India
| | - Debajyoti Bora
- Department of Statistics, Dibrugarh University, Dibrugarh, India
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Ayoub Moubareck C, Hammoudi Halat D, Akkawi C, Nabi A, AlSharhan MA, AlDeesi ZO, Peters CC, Celiloglu H, Karam Sarkis D. Role of outer membrane permeability, efflux mechanism, and carbapenemases in carbapenem-nonsusceptible Pseudomonas aeruginosa from Dubai hospitals: Results of the first cross-sectional survey. Int J Infect Dis 2019; 84:143-150. [PMID: 31204002 DOI: 10.1016/j.ijid.2019.04.027] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2019] [Revised: 04/21/2019] [Accepted: 04/24/2019] [Indexed: 10/26/2022] Open
Abstract
OBJECTIVES Carbapenem resistance in Pseudomonas aeruginosa is growing and results from variable mechanisms. The objectives of the current study were to investigate mechanisms of carbapenem resistance and genetic relatedness of P. aeruginosa isolates recovered in Dubai hospitals. METHODS From June 2015 through June 2016, carbapenem-nonsusceptible P. aeruginosa were collected from 4 hospitals in Dubai, and subjected to antimicrobial susceptibility testing, molecular investigation of carbapenemases by PCR-sequencing, analysis of outer membrane porin OprD2 and multidrug efflux channel MexAB-OprM levels by qPCR, and fingerprinting by ERIC-PCR. RESULTS Out of 1969 P. aeruginosa isolated during the study period, 471 (23.9%) showed reduced carbapenem susceptibility. Of these, 37 were analyzed and 32% of them produced VIM-type metallo-β-lactamases, including VIM-2, VIM-30, VIM-31, and VIM-42, while GES-5 and GES-9 co-existed with VIM in 5.4% of isolates. Outer membrane impermeability was observed in 73% of isolates and 75.6% displayed overproduced MexAB-OprM. ERIC-PCR revealed one large clone including most carbapenemase-producing isolates indicating clonal dissemination. CONCLUSION This is the first study on carbapenem-nonsusceptible P. aeruginosa from Dubai, incriminating VIM production as well as outer membrane permeability and efflux systems as resistance mechanisms. Further studies on carbapenem-nonsusceptible P. aeruginosa in Dubai are warranted for containment of such health hazard.
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Affiliation(s)
- Carole Ayoub Moubareck
- Microbiology Laboratory, School of Pharmacy, Saint-Joseph University, Beirut, Lebanon; College of Natural and Health Sciences, Zayed University, Dubai, United Arab Emirates
| | - Dalal Hammoudi Halat
- Microbiology Laboratory, School of Pharmacy, Saint-Joseph University, Beirut, Lebanon; Department of Pharmaceutical Sciences, School of Pharmacy, Lebanese International University, Beirut and Bekaa Campuses, Lebanon.
| | - Charbel Akkawi
- Microbiology Laboratory, School of Pharmacy, Saint-Joseph University, Beirut, Lebanon
| | - Anju Nabi
- Dubai Hospital, Dubai, United Arab Emirates
| | | | | | | | | | - Dolla Karam Sarkis
- Microbiology Laboratory, School of Pharmacy, Saint-Joseph University, Beirut, Lebanon
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Thirumalmuthu K, Devarajan B, Prajna L, Mohankumar V. Mechanisms of Fluoroquinolone and Aminoglycoside Resistance in Keratitis-AssociatedPseudomonas aeruginosa. Microb Drug Resist 2019; 25:813-823. [DOI: 10.1089/mdr.2018.0218] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Affiliation(s)
- Kannan Thirumalmuthu
- Department of Ocular Microbiology and Aravind Medical Research Foundation, Madurai, India
| | | | - Lalitha Prajna
- Department of Ocular Microbiology and Aravind Medical Research Foundation, Madurai, India
| | - Vidyarani Mohankumar
- Department of Ocular Microbiology and Aravind Medical Research Foundation, Madurai, India
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De Rosa A, Mutters NT, Mastroianni CM, Kaiser SJ, Günther F. Distribution of carbapenem resistance mechanisms in clinical isolates of XDR Pseudomonas aeruginosa. Eur J Clin Microbiol Infect Dis 2019; 38:1547-52. [PMID: 31152264 DOI: 10.1007/s10096-019-03585-0] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2019] [Revised: 05/07/2019] [Accepted: 05/09/2019] [Indexed: 01/11/2023]
Abstract
Our study aims to define the epidemiology of carbapenem resistance mechanisms in clinical isolates of Pseudomonas aeruginosa (PA). We evaluated 11,457 clinical PA strains isolated between 2009 and 2015 at the tertiary care University Hospital in Heidelberg, Germany. Thirty-four percent of the isolates (3867/11,457) were MDR (multidrug-resistant), 16% (1816/11,457) were XDR (extensively drug resistant), and less than 1% (82/11,457) had a PDR (pandrug-resistant) profile. Of those, 23% carried a carbapenemase gene (CPM positive) with 12% VIM-2, 10% VIM-1, and less than 1% IMP-1. Comparing MIC (minimal inhibitory concentration) distributions, the mean rank for meropenem, imipenem, gentamicin, and fosfomycin was significantly higher in the CPM-positive group than in the CPM-negative XDR group (p ≤ 0.004). oprD (outer membrane protein) mutations were found in 19/19 tested strains; 12/19 carried a CPM and had a higher mutation rate. Meropenem resistance was mostly associated with the presence of CPM. Only 1/19 strains was meropenem resistant in the absence of CPM genes; nevertheless, it carried an oprD mutation in a strategic site (loop 2). Of 19 CPM-negative strains tested, 7 (36%) showed EP (efflux pumps) hyperexpression versus 12 in the CPM-positive strains. In our study, nearly 50% of the PA isolates exhibited resistance to the tested first-line antibiotics. Our study also demonstrates that carbapenemase genes can be isolated in approximately 23% of XDR PA strains in our population. This finding supports the clinical relevance of PA driven by the possible presence of multiple resistance mechanisms acquired under exposure to antibiotics or by horizontal transfer of resistance genes.
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Ellappan K, Belgode Narasimha H, Kumar S. Coexistence of multidrug resistance mechanisms and virulence genes in carbapenem-resistant Pseudomonas aeruginosa strains from a tertiary care hospital in South India. J Glob Antimicrob Resist 2018; 12:37-43. [DOI: 10.1016/j.jgar.2017.08.018] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2017] [Revised: 08/27/2017] [Accepted: 08/31/2017] [Indexed: 10/18/2022] Open
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Lin HV, Massam-Wu T, Lin CP, Wang YA, Shen YC, Lu WJ, Hsu PH, Chen YH, Borges-Walmsley MI, Walmsley AR. The Vibrio cholerae var regulon encodes a metallo-β-lactamase and an antibiotic efflux pump, which are regulated by VarR, a LysR-type transcription factor. PLoS One 2017; 12:e0184255. [PMID: 28898293 DOI: 10.1371/journal.pone.0184255] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2017] [Accepted: 08/21/2017] [Indexed: 12/14/2022] Open
Abstract
The genome sequence of V. cholerae O1 Biovar Eltor strain N16961 has revealed a putative antibiotic resistance (var) regulon that is predicted to encode a transcriptional activator (VarR), which is divergently transcribed relative to the putative resistance genes for both a metallo-β-lactamase (VarG) and an antibiotic efflux-pump (VarABCDEF). We sought to test whether these genes could confer antibiotic resistance and are organised as a regulon under the control of VarR. VarG was overexpressed and purified and shown to have β-lactamase activity against penicillins, cephalosporins and carbapenems, having the highest activity against meropenem. The expression of VarABCDEF in the Escherichia coli (ΔacrAB) strain KAM3 conferred resistance to a range of drugs, but most significant resistance was to the macrolide spiramycin. A gel-shift analysis was used to determine if VarR bound to the promoter regions of the resistance genes. Consistent with the regulation of these resistance genes, VarR binds to three distinct intergenic regions, varRG, varGA and varBC located upstream and adjacent to varG, varA and varC, respectively. VarR can act as a repressor at the varRG promoter region; whilst this repression was relieved upon addition of β-lactams, these did not dissociate the VarR/varRG-DNA complex, indicating that the de-repression of varR by β-lactams is indirect. Considering that the genomic arrangement of VarR-VarG is strikingly similar to that of AmpR-AmpC system, it is possible that V. cholerae has evolved a system for resistance to the newer β-lactams that would prove more beneficial to the bacterium in light of current selective pressures.
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Moya B, Barcelo IM, Bhagwat S, Patel M, Bou G, Papp-Wallace KM, Bonomo RA, Oliver A. WCK 5107 (Zidebactam) and WCK 5153 Are Novel Inhibitors of PBP2 Showing Potent "β-Lactam Enhancer" Activity against Pseudomonas aeruginosa, Including Multidrug-Resistant Metallo-β-Lactamase-Producing High-Risk Clones. Antimicrob Agents Chemother 2017; 61:e02529-16. [PMID: 28289035 DOI: 10.1128/AAC.02529-16] [Citation(s) in RCA: 86] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2016] [Accepted: 02/24/2017] [Indexed: 12/23/2022] Open
Abstract
Zidebactam and WCK 5153 are novel β-lactam enhancers that are bicyclo-acyl hydrazides (BCH), derivatives of the diazabicyclooctane (DBO) scaffold, targeted for the treatment of serious infections caused by highly drug-resistant Gram-negative pathogens. In this study, we determined the penicillin-binding protein (PBP) inhibition profiles and the antimicrobial activities of zidebactam and WCK 5153 against Pseudomonas aeruginosa, including multidrug-resistant (MDR) metallo-β-lactamase (MBL)-producing high-risk clones. MIC determinations and time-kill assays were conducted for zidebactam, WCK 5153, and antipseudomonal β-lactams using wild-type PAO1, MexAB-OprM-hyperproducing (mexR), porin-deficient (oprD), and AmpC-hyperproducing (dacB) derivatives of PAO1, and MBL-expressing clinical strains ST175 (blaVIM-2) and ST111 (blaVIM-1). Furthermore, steady-state kinetics was used to assess the inhibitory potential of these compounds against the purified VIM-2 MBL. Zidebactam and WCK 5153 showed specific PBP2 inhibition and did not inhibit VIM-2 (apparent Ki [Kiapp] > 100 μM). MICs for zidebactam and WCK 5153 ranged from 2 to 32 μg/ml (amdinocillin MICs > 32 μg/ml). Time-kill assays revealed bactericidal activity of zidebactam and WCK 5153. LIVE-DEAD staining further supported the bactericidal activity of both compounds, showing spheroplast formation. Fixed concentrations (4 or 8 μg/ml) of zidebactam and WCK 5153 restored susceptibility to all of the tested β-lactams for each of the P. aeruginosa mutant strains. Likewise, antipseudomonal β-lactams (CLSI breakpoints), in combination with 4 or 8 μg/ml of zidebactam or WCK 5153, resulted in enhanced killing. Certain combinations determined full bacterial eradication, even with MDR MBL-producing high-risk clones. β-Lactam-WCK enhancer combinations represent a promising β-lactam "enhancer-based" approach to treat MDR P. aeruginosa infections, bypassing the need for MBL inhibition.
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Lv H, Li J, Wu Y, Garyali S, Wang Y. Transporter and its engineering for secondary metabolites. Appl Microbiol Biotechnol 2016; 100:6119-6130. [PMID: 27209041 DOI: 10.1007/s00253-016-7605-6] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2016] [Revised: 04/28/2016] [Accepted: 05/02/2016] [Indexed: 01/26/2023]
Abstract
Secondary metabolites possess a lot of biological activities, and to achieve their functions, transmembrane transportation is crucial. Elucidation of their transport mechanisms in the cell is critical for discovering ways to improve the production. Here, we have summarized the recent progresses for representative secondary metabolite transporters and also the strategies for uncovering the transporter systems in plants and microbes. We have also discussed the transporter engineering strategies being utilized for improving the heterologous natural product production, which exhibits promising future under the guide of synthetic biology.
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Affiliation(s)
- Huajun Lv
- Key Laboratory of Synthetic Biology, CAS Center for Excellence in Molecular Plant Sciences, Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai, 200032, China
| | - Jianhua Li
- Key Laboratory of Synthetic Biology, CAS Center for Excellence in Molecular Plant Sciences, Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai, 200032, China
| | - Yingying Wu
- Key Laboratory of Synthetic Biology, CAS Center for Excellence in Molecular Plant Sciences, Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai, 200032, China
| | - Sanjog Garyali
- Key Laboratory of Synthetic Biology, CAS Center for Excellence in Molecular Plant Sciences, Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai, 200032, China
| | - Yong Wang
- Key Laboratory of Synthetic Biology, CAS Center for Excellence in Molecular Plant Sciences, Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai, 200032, China.
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Fan X, Wu Y, Xiao M, Xu ZP, Kudinha T, Bazaj A, Kong F, Xu YC. Diverse Genetic Background of Multidrug-Resistant Pseudomonas aeruginosa from Mainland China, and Emergence of an Extensively Drug-Resistant ST292 Clone in Kunming. Sci Rep. 2016;6:26522. [PMID: 27198004 PMCID: PMC4873832 DOI: 10.1038/srep26522] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2016] [Accepted: 05/04/2016] [Indexed: 12/17/2022] Open
Abstract
For a better understanding of the multidrug resistant Pseudomonas aeruginosa (MDR-PA) epidemiology in mainland China, a nationwide surveillance network of 27 tertiary hospitals was established. Non-duplicate MDR-PA isolates from 254 cases of nosocomial infections, were collected during the period August 2011 to July 2012. Minimum inhibitory concentrations (MICs) of nine antimicrobial agents were determined by broth micro-dilution method according to the CLSI guidelines [M7-A10]. Genotyping analysis was performed by multilocus sequence typing (MLST) and pulsed-field gel electrophoresis (PFGE). The presence of acquired carbapenemases was also determined by molecular approaches for 233 carbapenem-resistant isolates. Carbapenemase genes were detected in 19 (8.2%) isolates, with 13 of these isolates encoding IMP-type enzymes, five with VIM-2, and one with KPC-2. MLST analysis revealed significant genetic diversity among the MDR-PA isolates studied, and 91 STs (including 17 novel STs) were identified. However, a long-term outbreak of an emerging extensively drug-resistant (XDR) ST292/PFGE genotype A clone was detected in a hospital from Southwest China. This study has demonstrated that MDR-PA in mainland China have evolved from diverse genetic backgrounds. Evidence of clonal dissemination of the organism and nosocomial outbreaks in some regions, suggest a need to strengthen existing infection control measures.
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Pan YP, Xu YH, Wang ZX, Fang YP, Shen JL. Overexpression of MexAB-OprM efflux pump in carbapenem-resistant Pseudomonas aeruginosa. Arch Microbiol 2016; 198:565-71. [PMID: 27060003 DOI: 10.1007/s00203-016-1215-7] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2015] [Revised: 03/12/2016] [Accepted: 03/28/2016] [Indexed: 11/27/2022]
Abstract
Efflux pump systems are one of the most important mechanisms conferring multidrug resistance in Pseudomonas aeruginosa. MexAB-OprM efflux pump is one of the largest multi-drug resistant efflux pumps with high-level expression, which is controlled by regulatory genes mexR, nalC, and nalD. This study investigated the role of efflux pump MexAB-OprM in 75 strains of carbapenem-resistant P. aeruginosa and evaluated the influence of point mutation of the regulatory genes. The minimum inhibitory concentrations of imipenem and meropenem, with or without MC207110, an efflux pump inhibitor, were determined by agar dilution method to select the positive strains for an overexpressed active efflux pump. Carba NP test and EDTA-disk synergy test were used for the detection of carbapenemase and metallo-β-lactamases, respectively. The gene mexA, responsible for the fusion protein structure, and the reference gene rpoD of the MexAB-OprM pump were amplified by real-time PCR. The quantity of relative mRNA expression was determined simultaneously. By PCR method, the efflux regulatory genes mexR, nalC, and nalD and outer membrane protein OprD2 were amplified for the strains showing overexpression of MexAB-OprM and subsequently analyzed by BLAST. Among the 75 P. aeruginosa strains, the prevalence of efflux pump-positive phenotype was 17.3 % (13/75). Carba NP test and EDTA-disk synergy test were all negative in the 13 strains. PCR assay results showed that ten strains overexpressed the MexAB-OprM efflux pump and were all positive for the regulatory genes mexR, nalC, and nalD. Sequence analysis indicated that of the ten isolates, nine had a mutation (Gly → Glu) at 71st amino acid position in NalC, and eight also had a mutation (Ser → Arg) at 209th position in NalC. Only one strain had a mutation (Thr → Ile) at the 158th amino acid position in NalD, whereas eight isolates had mutations in MexR. In conclusion, overexpression of efflux pump MexAB-OprM plays an important role in carbapenem-resistant P. aeruginosa. The mutations of regulatory genes may be a main factor contributing to overexpression of MexAB-OprM.
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Affiliation(s)
- Ya-Ping Pan
- Department of Laboratory Medicine, The First Affiliated Hospital of Anhui Medical University, Anhui Medical University, Hefei, Anhui, China
| | - Yuan-Hong Xu
- Department of Laboratory Medicine, The First Affiliated Hospital of Anhui Medical University, Anhui Medical University, Hefei, Anhui, China
| | - Zhong-Xin Wang
- Department of Laboratory Medicine, The First Affiliated Hospital of Anhui Medical University, Anhui Medical University, Hefei, Anhui, China
| | - Ya-Ping Fang
- Department of Laboratory Medicine, The Second Affiliated Hospital of Anhui Medical University, Anhui Medical University, Hefei, Anhui, China
| | - Ji-Lu Shen
- Department of Laboratory Medicine, The First Affiliated Hospital of Anhui Medical University, Anhui Medical University, Hefei, Anhui, China.
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