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Elings W, Chikunova A, van Zanten DB, Drenth R, Ahmad MUD, Blok AJ, Timmer M, Perrakis A, Ubbink M. Two β-Lactamase Variants with Reduced Clavulanic Acid Inhibition Display Different Millisecond Dynamics. Antimicrob Agents Chemother 2021; 65:e0262820. [PMID: 34031049 PMCID: PMC8284444 DOI: 10.1128/aac.02628-20] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2020] [Accepted: 05/07/2021] [Indexed: 11/20/2022] Open
Abstract
The β-lactamase of Mycobacterium tuberculosis, BlaC, is susceptible to inhibition by clavulanic acid. The ability of this enzyme to escape inhibition through mutation was probed using error-prone PCR combined with functional screening in Escherichia coli. The variant that was found to confer the most inhibitor resistance, K234R, as well as variant G132N that was found previously were characterized using X-ray crystallography and nuclear magnetic resonance (NMR) relaxation experiments to probe structural and dynamic properties. The G132N mutant exists in solution in two almost equally populated conformations that exchange with a rate of ca. 88 s-1. The conformational change affects a broad region of the enzyme. The crystal structure reveals that the Asn132 side chain forces the peptide bond between Ser104 and Ile105 in a cis-conformation. The crystal structure suggests multiple conformations for several side chains (e.g., Ser104 and Ser130) and a short loop (positions 214 to 216). In the K234R mutant, the active-site dynamics are significantly diminished with respect to the wild-type enzyme. These results show that multiple evolutionary routes are available to increase inhibitor resistance in BlaC and that active-site dynamics on the millisecond time scale are not required for catalytic function.
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Affiliation(s)
- Wouter Elings
- Leiden Institute of Chemistry, Leiden University, Leiden, The Netherlands
| | | | | | - Ralphe Drenth
- Leiden Institute of Chemistry, Leiden University, Leiden, The Netherlands
| | - Misbha Ud Din Ahmad
- Division of Biochemistry, the Netherlands Cancer Institute, Amsterdam, The Netherlands
- Oncode Institute, Amsterdam, The Netherlands
| | - Anneloes J. Blok
- Leiden Institute of Chemistry, Leiden University, Leiden, The Netherlands
| | - Monika Timmer
- Leiden Institute of Chemistry, Leiden University, Leiden, The Netherlands
| | - Anastassis Perrakis
- Division of Biochemistry, the Netherlands Cancer Institute, Amsterdam, The Netherlands
- Oncode Institute, Amsterdam, The Netherlands
| | - Marcellus Ubbink
- Leiden Institute of Chemistry, Leiden University, Leiden, The Netherlands
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2
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Galani I, Karaiskos I, Giamarellou H. Multidrug-resistant Klebsiella pneumoniae: mechanisms of resistance including updated data for novel β-lactam-β-lactamase inhibitor combinations. Expert Rev Anti Infect Ther 2021; 19:1457-1468. [PMID: 33945387 DOI: 10.1080/14787210.2021.1924674] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Introduction: Multi-drug-resistant Klebsiella pneumoniae is currently one of the most pressing emerging issues in bacterial resistance. Treatment of K.pneumoniae infections is often problematic due to the lack of available therapeutic options, with a relevant impact in terms of morbidity, mortality and healthcare-associated costs. Soon after the launch of Ceftazidime-Avibactam, one of the approved new β-lactam/β-lactamase inhibitor combinations, reports of ceftazidime-avibactam-resistant strains developing resistance during treatment were published. Being a hospital-associated pathogen, K.pneumoniae is continuously exposed to multiple antibiotics resulting in constant selective pressure, which in turn leads to additional mutations that are positively selected.Areas covered: Herein the authors present the K.pneumoniae mechanisms of resistance to different antimicrobials, including updated data for ceftazidime-avibactam.Expert opinion: K.pneumoniae is a nosocomial pathogen commonly implicated in hospital outbreaks with a propensity for antimicrobial resistance toward mainstay β-lactam antibiotics and multiple other antibiotic classes. Following the development of drug resistance and understanding the mechanisms involved, we can improve the efficacy of current antimicrobials, by applying careful stewardship and rational use to preserve their potential utility. The knowledge on antibiotic resistance mechanisms should be used to inform the design of novel therapeutic agents that might not be subject to, or can circumvent, mechanisms of resistance.
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Affiliation(s)
- Irene Galani
- Medicine, Infectious Diseases Laboratory, 4thDepartment of Internal Medicine, National and Kapodistrian University of Athens, Athens, Greece
| | - Ilias Karaiskos
- 1st Department of Internal Medicine-Infectious Diseases, Hygeia General Hospital, Athens, Greece
| | - Helen Giamarellou
- 1 Department of Internal Medicine-Infectious Diseases, Hygeia General Hospital, Athens, Greece
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3
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Soeung V, Lu S, Hu L, Judge A, Sankaran B, Prasad BVV, Palzkill T. A drug-resistant β-lactamase variant changes the conformation of its active-site proton shuttle to alter substrate specificity and inhibitor potency. J Biol Chem 2020; 295:18239-18255. [PMID: 33109613 DOI: 10.1074/jbc.ra120.016103] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2020] [Revised: 10/22/2020] [Indexed: 11/06/2022] Open
Abstract
Lys234 is one of the residues present in class A β-lactamases that is under selective pressure due to antibiotic use. Located adjacent to proton shuttle residue Ser130, it is suggested to play a role in proton transfer during catalysis of the antibiotics. The mechanism underpinning how substitutions in this position modulate inhibitor efficiency and substrate specificity leading to drug resistance is unclear. The K234R substitution identified in several inhibitor-resistant β-lactamase variants is associated with decreased potency of the inhibitor clavulanic acid, which is used in combination with amoxicillin to overcome β-lactamase-mediated antibiotic resistance. Here we show that for CTX-M-14 β-lactamase, whereas Lys234 is required for hydrolysis of cephalosporins such as cefotaxime, either lysine or arginine is sufficient for hydrolysis of ampicillin. Further, by determining the acylation and deacylation rates for cefotaxime hydrolysis, we show that both rates are fast, and neither is rate-limiting. The K234R substitution causes a 1500-fold decrease in the cefotaxime acylation rate but a 5-fold increase in kcat for ampicillin, suggesting that the K234R enzyme is a good penicillinase but a poor cephalosporinase due to slow acylation. Structural results suggest that the slow acylation by the K234R enzyme is due to a conformational change in Ser130, and this change also leads to decreased inhibition potency of clavulanic acid. Because other inhibitor resistance mutations also act through changes at Ser130 and such changes drastically reduce cephalosporin but not penicillin hydrolysis, we suggest that clavulanic acid paired with an oxyimino-cephalosporin rather than penicillin would impede the evolution of resistance.
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Affiliation(s)
- Victoria Soeung
- Department of Pharmacology and Chemical Biology, Baylor College of Medicine, Houston, Texas, USA
| | - Shuo Lu
- Department of Pharmacology and Chemical Biology, Baylor College of Medicine, Houston, Texas, USA
| | - Liya Hu
- Department of Biochemistry and Molecular Biology, Baylor College of Medicine, Houston, Texas, USA
| | - Allison Judge
- Department of Biochemistry and Molecular Biology, Baylor College of Medicine, Houston, Texas, USA
| | - Banumathi Sankaran
- Department of Molecular Biophysics and Integrated Bioimaging, Berkeley Center for Structural Biology, Lawrence Berkeley National Laboratory, Berkeley, California, USA
| | - B V Venkataram Prasad
- Department of Biochemistry and Molecular Biology, Baylor College of Medicine, Houston, Texas, USA; Department of Molecular Virology and Microbiology, Baylor College of Medicine, Houston, Texas, USA
| | - Timothy Palzkill
- Department of Pharmacology and Chemical Biology, Baylor College of Medicine, Houston, Texas, USA; Department of Biochemistry and Molecular Biology, Baylor College of Medicine, Houston, Texas, USA; Department of Molecular Virology and Microbiology, Baylor College of Medicine, Houston, Texas, USA.
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4
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Voulgari E, Kotsakis SD, Giannopoulou P, Perivolioti E, Tzouvelekis LS, Miriagou V. Detection in two hospitals of transferable ceftazidime-avibactam resistance in Klebsiella pneumoniae due to a novel VEB β-lactamase variant with a Lys234Arg substitution, Greece, 2019. ACTA ACUST UNITED AC 2020; 25. [PMID: 31964461 PMCID: PMC6976883 DOI: 10.2807/1560-7917.es.2020.25.2.1900766] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Two ceftazidime-avibactam (CAZ-AVI)-resistant Klebsiella pneumoniae carbapenemase (KPC)-positive K. pneumoniae strains, including one pandrug resistant, were isolated in 2019 from two Greek hospitals. The strains were sequence types (ST)s 258 and 147 and both harboured similar self-transmissible IncA/C2 plasmids encoding a novel Lys234Arg variant of the Vietnamese extended-spectrum β-lactamase (VEB)-1, not inhibited by AVI (VEB-25). Conjugal transfer of VEB-25-encoding plasmids to Escherichia coli yielded CAZ-AVI-resistant clones, supporting that VEB-25 is directly linked to the derived phenotype.
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Affiliation(s)
- E Voulgari
- Laboratory of Bacteriology, Hellenic Pasteur Institute, Athens, Greece
| | - S D Kotsakis
- Laboratory of Bacteriology, Hellenic Pasteur Institute, Athens, Greece
| | - P Giannopoulou
- Department of Clinical Microbiology, Thriassio General Hospital, Elefsina, Greece
| | - E Perivolioti
- Department of Clinical Microbiology, Evangelismos General Hospital, Athens, Greece
| | - L S Tzouvelekis
- Department of Microbiology, Medical School, University of Athens, Athens, Greece.,Laboratory of Bacteriology, Hellenic Pasteur Institute, Athens, Greece
| | - V Miriagou
- Laboratory of Bacteriology, Hellenic Pasteur Institute, Athens, Greece
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5
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Galani I, Karaiskos I, Souli M, Papoutsaki V, Galani L, Gkoufa A, Antoniadou A, Giamarellou H. Outbreak of KPC-2-producing Klebsiella pneumoniae endowed with ceftazidime-avibactam resistance mediated through a VEB-1-mutant (VEB-25), Greece, September to October 2019. ACTA ACUST UNITED AC 2020; 25. [PMID: 31992391 PMCID: PMC6988274 DOI: 10.2807/1560-7917.es.2020.25.3.2000028] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
From September to October 2019, seven patients colonised or infected with a ceftazidime-avibactam (CZA)-resistant Klebsiella pneumoniae carbapenemase (KPC)-2-producing K. pneumoniae were detected in two intensive care units of a Greek general hospital. The outbreak strain was sequence type (ST)147 and co-produced KPC-2 and the novel plasmid-borne Vietnamese extended-spectrum β-lactamase (VEB)-25 harbouring a K234R substitution associated with CZA resistance. Epidemiological investigations revealed that the resistance was probably acquired by horizontal transmission independently from previous CZA exposure.
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Affiliation(s)
- Irene Galani
- Infectious Diseases Laboratory, 4th Department of Internal Medicine, National and Kapodistrian University of Athens, Athens, Greece
| | - Ilias Karaiskos
- 1st Internal Medicine & Infectious Diseases Department, Hygeia General Hospital, Athens, Greece
| | - Maria Souli
- Infectious Diseases Laboratory, 4th Department of Internal Medicine, National and Kapodistrian University of Athens, Athens, Greece
| | | | - Lamprini Galani
- 1st Internal Medicine & Infectious Diseases Department, Hygeia General Hospital, Athens, Greece
| | - Aikaterini Gkoufa
- 1st Internal Medicine & Infectious Diseases Department, Hygeia General Hospital, Athens, Greece
| | - Anastasia Antoniadou
- Infectious Diseases Laboratory, 4th Department of Internal Medicine, National and Kapodistrian University of Athens, Athens, Greece
| | - Helen Giamarellou
- 1st Internal Medicine & Infectious Diseases Department, Hygeia General Hospital, Athens, Greece
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6
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Jones-Dias D, Carvalho AS, Moura IB, Manageiro V, Igrejas G, Caniça M, Matthiesen R. Quantitative proteome analysis of an antibiotic resistant Escherichia coli exposed to tetracycline reveals multiple affected metabolic and peptidoglycan processes. J Proteomics 2016; 156:20-28. [PMID: 28043878 DOI: 10.1016/j.jprot.2016.12.017] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2016] [Revised: 12/20/2016] [Accepted: 12/27/2016] [Indexed: 12/21/2022]
Abstract
Tetracyclines are among the most commonly used antibiotics administrated to farm animals for disease treatment and prevention, contributing to the worldwide increase in antibiotic resistance in animal and human pathogens. Although tetracycline mechanisms of resistance are well known, the role of metabolism in bacterial reaction to antibiotic stress is still an important assignment and could contribute to the understanding of tetracycline related stress response. In this study, spectral counts-based label free quantitative proteomics has been applied to study the response to tetracycline of the environmental-borne Escherichia coli EcAmb278 isolate soluble proteome. A total of 1484 proteins were identified by high resolution mass spectrometry at a false discovery rate threshold of 1%, of which 108 were uniquely identified under absence of tetracycline whereas 126 were uniquely identified in presence of tetracycline. These proteins revealed interesting difference in e.g. proteins involved in peptidoglycan-based cell wall proteins and energy metabolism. Upon treatment, 12 proteins were differentially regulated showing more than 2-fold change and p<0.05 (p value corrected for multiple testing). This integrated study using high resolution mass spectrometry based label-free quantitative proteomics to study tetracycline antibiotic response in the soluble proteome of resistant E. coli provides novel insight into tetracycline related stress. SIGNIFICANCE The lack of new antibiotics to fight infections caused by multidrug resistant microorganisms has motivated the use of old antibiotics, and the search for new drug targets. The evolution of antibiotic resistance is complex, but it is known that agroecosystems play an important part in the selection of antibiotic resistance bacteria. Tetracyclines are still used as phytopharmaceutical agents in crops, selecting resistant bacteria and changing the ecology of farm soil. Little is known about the metabolic response of genetically resistant populations to antibiotic exposure. Indeed, to date there are no quantitative tetracycline resistance studies performed with the latest generation of high resolution mass spectrometers allowing high mass accuracy in both MS and MS/MS scans. Here, we report the proteome profiling of a soil-borne Escherichia coli upon tetracycline stress, so that this new perspective could provide a broaden understanding of the metabolic responses of E. coli to a widely used antibiotic.
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Affiliation(s)
- Daniela Jones-Dias
- National Reference Laboratory of Antibiotic Resistances and Heathcare Associated Infections, Department of Infectious Diseases, National Institute of Health Doutor Ricardo Jorge, Lisbon, Portugal; Centre for the Studies of Animal Science, Institute of Agrarian and Agri-Food Sciences and Technologies, Oporto University, Oporto, Portugal
| | - Ana Sofia Carvalho
- Computational and Experimental Biology Group, Department of Health Promotion and Chronic Diseases, National Institute of Health Doutor Ricardo Jorge, Lisbon, Portugal
| | - Inês Barata Moura
- National Reference Laboratory of Antibiotic Resistances and Heathcare Associated Infections, Department of Infectious Diseases, National Institute of Health Doutor Ricardo Jorge, Lisbon, Portugal; Centre for the Studies of Animal Science, Institute of Agrarian and Agri-Food Sciences and Technologies, Oporto University, Oporto, Portugal
| | - Vera Manageiro
- National Reference Laboratory of Antibiotic Resistances and Heathcare Associated Infections, Department of Infectious Diseases, National Institute of Health Doutor Ricardo Jorge, Lisbon, Portugal; Centre for the Studies of Animal Science, Institute of Agrarian and Agri-Food Sciences and Technologies, Oporto University, Oporto, Portugal
| | - Gilberto Igrejas
- Functional Genomics and Proteomics Unit, Department of Genetic and Biotechnology, University of Trás-os-Montes and Alto Douro, Vila Real, Portugal; UCIBIO-REQUIMTE, Faculty of Science and Technology, New University of Lisbon, Monte da Caparica, Portugal
| | - Manuela Caniça
- National Reference Laboratory of Antibiotic Resistances and Heathcare Associated Infections, Department of Infectious Diseases, National Institute of Health Doutor Ricardo Jorge, Lisbon, Portugal.
| | - Rune Matthiesen
- Computational and Experimental Biology Group, Department of Health Promotion and Chronic Diseases, National Institute of Health Doutor Ricardo Jorge, Lisbon, Portugal
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7
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Baig MH, Balaramnavar VM, Wadhwa G, Khan AU. Homology modeling and virtual screening of inhibitors against TEM- and SHV-type-resistant mutants: A multilayer filtering approach. Biotechnol Appl Biochem 2015; 62:669-80. [PMID: 25779642 DOI: 10.1002/bab.1370] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2014] [Accepted: 03/12/2015] [Indexed: 11/09/2022]
Abstract
TEM and SHV are class-A-type β-lactamases commonly found in Escherichia coli and Klebsiella pneumoniae. Previous studies reported S130G and K234R mutations in SHVs to be 41- and 10-fold more resistant toward clavulanic acid than SHV-1, respectively, whereas TEM S130G and R244S also showed the same level of resistance. These selected mutants confer higher level of resistance against clavulanic acid. They also show little susceptibility against other commercially available β-lactamase inhibitors. In this study, we have used docking-based virtual screening approach in order to screen potential inhibitors against some of the major resistant mutants of SHV and TEM types β-lactamase. Two different inhibitor-resistant mutants from SHV and TEM were selected. Moreover, we have retained the active site water molecules within each enzyme. Active site water molecules were placed within modeled structure of the mutant whose structure was unavailable with protein databank. The novelty of this work lies in the use of multilayer virtual screening approach for the prediction of best and accurate results. We are reporting five inhibitors on the basis of their efficacy against all the selected resistant mutants. These inhibitors were selected on the basis of their binding efficacies and pharmacophore features.
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Affiliation(s)
- Mohammad H Baig
- Interdisciplinary Biotechnology Unit, Aligarh Muslim University, Aligarh, India.,School of Biotechnology, Yeungnam University, Gyeongsan, Republic of Korea
| | - Vishal M Balaramnavar
- Division of Medicinal Chemistry and Drug Discovery, Global Institute of Pharmaceutical Education and Research, Kashipur, Udham Singh Nagar, Uttarakhand, India
| | - Gulshan Wadhwa
- Department of Biotechnology, Government of India, New Delhi, India
| | - Asad U Khan
- Interdisciplinary Biotechnology Unit, Aligarh Muslim University, Aligarh, India
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8
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Egesborg P, Carlettini H, Volpato JP, Doucet N. Combinatorial active-site variants confer sustained clavulanate resistance in BlaC β-lactamase from Mycobacterium tuberculosis. Protein Sci 2014; 24:534-44. [PMID: 25492589 DOI: 10.1002/pro.2617] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2014] [Accepted: 12/03/2014] [Indexed: 11/10/2022]
Abstract
Bacterial resistance to β-lactam antibiotics is a global issue threatening the success of infectious disease treatments worldwide. Mycobacterium tuberculosis has been particularly resilient to β-lactam treatment, primarily due to the chromosomally encoded BlaC β-lactamase, a broad-spectrum hydrolase that renders ineffective the vast majority of relevant β-lactam compounds currently in use. Recent laboratory and clinical studies have nevertheless shown that specific β-lactam-BlaC inhibitor combinations can be used to inhibit the growth of extensively drug-resistant strains of M. tuberculosis, effectively offering new tools for combined treatment regimens against resistant strains. In the present work, we performed combinatorial active-site replacements in BlaC to demonstrate that specific inhibitor-resistant (IRT) substitutions at positions 69, 130, 220, and/or 234 can act synergistically to yield active-site variants with several thousand fold greater in vitro resistance to clavulanate, the most common clinical β-lactamase inhibitor. While most single and double variants remain sensitive to clavulanate, double mutants R220S-K234R and S130G-K234R are substantially less affected by time-dependent clavulanate inactivation, showing residual β-lactam hydrolytic activities of 46% and 83% after 24 h incubation with a clinically relevant inhibitor concentration (5 μg/ml, 25 µM). These results demonstrate that active-site alterations in BlaC yield resistant variants that remain active and stable over prolonged bacterial generation times compatible with mycobacterial proliferation. These results also emphasize the formidable adaptive potential of inhibitor-resistant substitutions in β-lactamases, potentially casting a shadow on specific β-lactam-BlaC inhibitor combination treatments against M. tuberculosis.
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Affiliation(s)
- Philippe Egesborg
- INRS-Institut Armand-Frappier, Université du Québec, Laval, Québec, H7V 1B7, Canada
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9
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Rodkey EA, Winkler ML, Bethel CR, Pagadala SRR, Buynak JD, Bonomo RA, van den Akker F. Penam sulfones and β-lactamase inhibition: SA2-13 and the importance of the C2 side chain length and composition. PLoS One 2014; 9:e85892. [PMID: 24454944 PMCID: PMC3894197 DOI: 10.1371/journal.pone.0085892] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2013] [Accepted: 12/03/2013] [Indexed: 02/01/2023] Open
Abstract
β-Lactamases are the major reason β-lactam resistance is seen in Gram-negative bacteria. To combat this resistance mechanism, β-lactamase inhibitors are currently being developed. Presently, there are only three that are in clinical use (clavulanate, sulbactam and tazobactam). In order to address this important medical need, we explored a new inhibition strategy that takes advantage of a long-lived inhibitory trans-enamine intermediate. SA2-13 was previously synthesized and shown to have a lower k(react) than tazobactam. We investigated here the importance of the carboxyl linker length and composition by synthesizing three analogs of SA2-13 (PSR-4-157, PSR-4-155, and PSR-3-226). All SA2-13 analogs yielded higher turnover numbers and k(react) compared to SA2-13. We next demonstrated using protein crystallography that increasing the linker length by one carbon allowed for better capture of a trans-enamine intermediate; in contrast, this trans-enamine intermediate did not occur when the C2 linker length was decreased by one carbon. If the linker was altered by both shortening it and changing the carboxyl moiety into a neutral amide moiety, the stable trans-enamine intermediate in wt SHV-1 did not form; this intermediate could only be observed when a deacylation deficient E166A variant was studied. We subsequently studied SA2-13 against a relatively recently discovered inhibitor-resistant (IR) variant of SHV-1, SHV K234R. Despite the alteration in the mechanism of resistance due to the K→R change in this variant, SA2-13 was effective at inhibiting this IR enzyme and formed a trans-enamine inhibitory intermediate similar to the intermediate seen in the wt SHV-1 structure. Taken together, our data reveals that the C2 side chain linker length and composition profoundly affect the formation of the trans-enamine intermediate of penam sulfones. We also show that the design of SA2-13 derivatives offers promise against IR SHV β-lactamases that possess the K234R substitution.
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Affiliation(s)
- Elizabeth A. Rodkey
- Department of Biochemistry, Case Western Reserve University, Cleveland, Ohio, United States of America
| | - Marisa L. Winkler
- Department of Molecular Biology and Microbiology, Case Western Reserve University, Cleveland, Ohio, United States of America
- Research Division, Louis Stokes Cleveland Veterans Affairs Medical Center, Cleveland, Ohio, United States of America
| | - Christopher R. Bethel
- Research Division, Louis Stokes Cleveland Veterans Affairs Medical Center, Cleveland, Ohio, United States of America
| | | | - John D. Buynak
- Department of Chemistry, Southern Methodist University, Dallas, Texas, United States of America
| | - Robert A. Bonomo
- Department of Molecular Biology and Microbiology, Case Western Reserve University, Cleveland, Ohio, United States of America
- Research Division, Louis Stokes Cleveland Veterans Affairs Medical Center, Cleveland, Ohio, United States of America
- Department of Medicine, Case Western Reserve University, Cleveland, Ohio, United States of America
- Department of Pharmacology, Case Western Reserve University, Cleveland, Ohio, United States of America
- * E-mail: (RAB); (FVDA)
| | - Focco van den Akker
- Department of Biochemistry, Case Western Reserve University, Cleveland, Ohio, United States of America
- * E-mail: (RAB); (FVDA)
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10
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Detection of resistance to beta-lactamase inhibitors in strains with CTX-M beta-lactamases: a multicenter external proficiency study using a well-defined collection of Escherichia coli strains. J Clin Microbiol 2013; 52:122-9. [PMID: 24153133 DOI: 10.1128/jcm.02340-13] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Under the auspices of the Spanish Society for Infectious Diseases and Clinical Microbiology Quality Control program, 14 Escherichia coli strains masked as blood culture isolates were sent to 68 clinical microbiology laboratories for antimicrobial susceptibility testing to β-lactam antibiotics. This collection included three control strains (E. coli ATCC 25922, an IRT-2 producer, and a CMY-2 producer), six isogenic strains with or without the OmpF porin and expressing CTX-M β-lactamases (CTX-M-1, CTX-M-15, and CTX-M-14), one strain carrying a double mechanism for β-lactam resistance (i.e., carrying CTX-M-15 and OXA-1 enzymes), and four strains carrying CTX-M variants with different levels of resistance to β-lactams and β-lactam-β-lactamase inhibitor (BLBLI) combinations. The main objective of the study was to ascertain how these variants with reduced susceptibilities to BLBLIs are identified in clinical microbiology laboratories. CTX-M variants with high resistance to BLBLIs were mainly identified as inhibitor-resistant TEM (IRT) enzymes (68.0%); however, isogenic CTX-M mutant strains with reduced susceptibilities to BLBLIs and cephalosporins were mainly associated with extended-spectrum β-lactamase production alone (51 to 80%) or in combination with other mechanisms (14 to 31%). Concerning all β-lactams tested, the overall interpretative discrepancy rate was 11.5%, of which 38.1% were the consequence of postreading changes in the clinical categories when a resistance mechanism was inferred. Therefore, failure to recognize these complex phenotypes might contribute to an explanation of their apparent absence in the clinical setting and might lead to inadequate drug treatment selection. A proposal for improving recognition is to adhere strictly to the current CLSI or EUCAST guidelines for detecting reduced susceptibility to BLBLI combinations, without any interpretative modification.
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11
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The evolutionary histories of clinical and environmental SHV β-lactamases are intertwined. J Mol Evol 2013; 76:388-93. [PMID: 23860538 DOI: 10.1007/s00239-013-9574-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2013] [Accepted: 07/05/2013] [Indexed: 10/26/2022]
Abstract
The rise of antibiotic-resistant pathogens focuses our attention on the source of antibiotic resistance genes, on the existence of these genes in environments exposed to little or no antibiotics, and on the relationship between resistance genes found in the clinic and those encountered in non-clinical settings. Here, we address the evolutionary history of a class of resistance genes, the SHV β-lactamases. We focus on bla SHV genes isolated both from clinical and non-clinical sources and show that clinically important resistance determinants arise repeatedly from within a diverse pool of bla SHV genes present in the environment. While our results argue against the notion of a single common origin for all clinically derived bla SHV genes, we detect a characteristic selective signature shaping this protein in clinical environments. This clinical signature reveals the joint action of purifying and positive selection on specific residues, including those known to confer extended-spectrum activity. Surprisingly, antibiotic resistance genes isolated from non-clinical-and presumably antibiotic-free-settings also experience the joint action of purifying and positive selection. The picture that emerges undercuts the notion of a separate reservoir of antibiotic resistance genes confined only to clinical settings. Instead, we argue for the presence of a single extensive and variable pool of antibiotic resistance genes present in the environment.
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12
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Winkler ML, Rodkey EA, Taracila MA, Drawz SM, Bethel CR, Papp-Wallace KM, Smith KM, Xu Y, Dwulit-Smith JR, Romagnoli C, Caselli E, Prati F, van den Akker F, Bonomo RA. Design and exploration of novel boronic acid inhibitors reveals important interactions with a clavulanic acid-resistant sulfhydryl-variable (SHV) β-lactamase. J Med Chem 2013; 56:1084-97. [PMID: 23252553 PMCID: PMC3943433 DOI: 10.1021/jm301490d] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Inhibitor resistant (IR) class A β-lactamases pose a significant threat to many current antibiotic combinations. The K234R substitution in the SHV β-lactamase, from Klebsiella pneumoniae , results in resistance to ampicillin/clavulanate. After site-saturation mutagenesis of Lys-234 in SHV, microbiological and biochemical characterization of the resulting β-lactamases revealed that only -Arg conferred resistance to ampicillin/clavulanate. X-ray crystallography revealed two conformations of Arg-234 and Ser-130 in SHV K234R. The movement of Ser-130 is the principal cause of the observed clavulanate resistance. A panel of boronic acid inhibitors was designed and tested against SHV-1 and SHV K234R. A chiral ampicillin analogue was discovered to have a 2.4 ± 0.2 nM K(i) for SHV K234R; the chiral ampicillin analogue formed a more complex hydrogen-bonding network in SHV K234R vs SHV-1. Consideration of the spatial position of Ser-130 and Lys-234 and this hydrogen-bonding network will be important in the design of novel antibiotics targeting IR β-lactamases.
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Affiliation(s)
- Marisa L. Winkler
- Department of Microbiology and Molecular Biology, Case Western Reserve University, Cleveland, Ohio 44106, United States
| | - Elizabeth A. Rodkey
- Department of Biochemistry, Case Western Reserve University, Cleveland, Ohio 44106, United States
| | - Magdalena A. Taracila
- Department of Medicine, Case Western Reserve University, Cleveland, Ohio 44106, United States
| | - Sarah M. Drawz
- Department of Pathology, Case Western Reserve University, Cleveland, Ohio 44106, United States
| | - Christopher R. Bethel
- Research Service, Louis Stokes Cleveland Department of Veterans Affairs Medical Center, Cleveland, Ohio 44106, United States
| | - Krisztina M. Papp-Wallace
- Department of Medicine, Case Western Reserve University, Cleveland, Ohio 44106, United States,Research Service, Louis Stokes Cleveland Department of Veterans Affairs Medical Center, Cleveland, Ohio 44106, United States
| | - Kerri M. Smith
- Department of Chemistry, Cleveland State University, Cleveland Ohio 44115, United States
| | - Yan Xu
- Department of Chemistry, Cleveland State University, Cleveland Ohio 44115, United States
| | - Jeffrey R. Dwulit-Smith
- Department of Biochemistry, Case Western Reserve University, Cleveland, Ohio 44106, United States
| | - Chiara Romagnoli
- Department of Life Sciences, University of Modena and Reggio Emilia, Modena, Italy
| | - Emilia Caselli
- Department of Life Sciences, University of Modena and Reggio Emilia, Modena, Italy
| | - Fabio Prati
- Department of Life Sciences, University of Modena and Reggio Emilia, Modena, Italy
| | - Focco van den Akker
- Department of Biochemistry, Case Western Reserve University, Cleveland, Ohio 44106, United States,Corresponding Author. For F.v.d.A.: . For R.A.B.: phone, (216) 791-3800 ext 4399; ; address, Robert A. Bonomo, MD, 10701 East Boulevard, Cleveland, Ohio, 44106
| | - Robert A. Bonomo
- Department of Microbiology and Molecular Biology, Case Western Reserve University, Cleveland, Ohio 44106, United States,Department of Medicine, Case Western Reserve University, Cleveland, Ohio 44106, United States,Department of Pharmacology, Case Western Reserve University, Cleveland, Ohio 44106, United States,Research Service, Louis Stokes Cleveland Department of Veterans Affairs Medical Center, Cleveland, Ohio 44106, United States,Corresponding Author. For F.v.d.A.: . For R.A.B.: phone, (216) 791-3800 ext 4399; ; address, Robert A. Bonomo, MD, 10701 East Boulevard, Cleveland, Ohio, 44106
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Baig MH, Shakil S, Khan AU. Homology modeling and docking study of recent SHV type β-lactamses with traditional and novel inhibitors: an in silico approach to combat problem of multiple drug resistance in various infections. Med Chem Res 2012. [DOI: 10.1007/s00044-011-9736-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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Substitutions at position 105 in SHV family β-lactamases decrease catalytic efficiency and cause inhibitor resistance. Antimicrob Agents Chemother 2012; 56:5678-86. [PMID: 22908166 DOI: 10.1128/aac.00711-12] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Ambler position 105 in class A β-lactamases is implicated in resistance to clavulanic acid, although no clinical isolates with mutations at this site have been reported. We hypothesized that Y105 is important in resistance to clavulanic acid because changes in positioning of the inhibitor for ring oxygen protonation could occur. In addition, resistance to bicyclic 6-methylidene penems, which are interesting structural probes that inhibit all classes of serine β-lactamases with nanomolar affinity, might emerge with substitutions at position 105, especially with nonaromatic substitutions. All 19 variants of SHV-1 with variations at position 105 were prepared. Antimicrobial susceptibility testing showed that Escherichia coli DH10B expressing Y105 variants retained activity against ampicillin, except for the Y105L variant, which was susceptible to all β-lactams, similar to the case for the host control strain. Several variants had elevated MICs to ampicillin-clavulanate. However, all the variants remained susceptible to piperacillin in combination with a penem inhibitor (MIC, ≤2/4 mg/liter). The Y105E, -F, -M, and -R variants demonstrated reduced catalytic efficiency toward ampicillin compared to the wild-type (WT) enzyme, which was caused by increased K(m). Clavulanic acid and penem K(i) values were also increased for some of the variants, especially Y105E. Mutagenesis at position 105 in SHV yields mutants resistant to clavulanate with reduced catalytic efficiency for ampicillin and nitrocefin, similar to the case for the class A carbapenemase KPC-2. Our modeling analyses suggest that resistance is due to oxyanion hole distortion. Susceptibility to a penem inhibitor is retained although affinity is decreased, especially for the Y105E variant. Residue 105 is important to consider when designing new inhibitors.
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Characterization of the inhibitor-resistant SHV β-lactamase SHV-107 in a clinical Klebsiella pneumoniae strain coproducing GES-7 enzyme. Antimicrob Agents Chemother 2011; 56:1042-6. [PMID: 22083476 DOI: 10.1128/aac.01444-10] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The clinical Klebsiella pneumoniae INSRA6884 strain exhibited nonsusceptibility to all penicillins tested (MICs of 64 to >2,048 μg/ml). The MICs of penicillins were weakly reduced by clavulanate (from 2,048 to 512 μg/ml), and tazobactam restored piperacillin susceptibility. Molecular characterization identified the genes bla(GES-7) and a new β-lactamase gene, bla(SHV-107), which encoded an enzyme that differed from SHV-1 by the amino acid substitutions Leu35Gln and Thr235Ala. The SHV-107-producing Escherichia coli strain exhibited only a β-lactam resistance phenotype with respect to amoxicillin, ticarcillin, and amoxicillin-clavulanate combination. The kinetic parameters of the purified SHV-107 enzyme revealed a high affinity for penicillins. However, catalytic efficiency for these antibiotics was lower for SHV-107 than for SHV-1. No hydrolysis was detected against oxyimino-β-lactams. The 50% inhibitory concentration (IC(50)) for clavulanic acid was 9-fold higher for SHV-107 than for SHV-1, but the inhibitory effects of tazobactam were unchanged. Molecular dynamics simulation suggested that the Thr235Ala substitution affects the accommodation of clavulanate in the binding site and therefore its inhibitory activity.
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Ripoll A, Baquero F, Novais Â, Rodríguez-Domínguez MJ, Turrientes MC, Cantón R, Galán JC. In vitro selection of variants resistant to beta-lactams plus beta-lactamase inhibitors in CTX-M beta-lactamases: predicting the in vivo scenario? Antimicrob Agents Chemother 2011; 55:4530-6. [PMID: 21788458 PMCID: PMC3186957 DOI: 10.1128/aac.00178-11] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2011] [Revised: 04/25/2011] [Accepted: 07/16/2011] [Indexed: 01/23/2023] Open
Abstract
CTX-M β-lactamases are the most prevalent group of enzymes within the extended-spectrum β-lactamases (ESBL). The therapeutic options for CTX-M-carrying isolates are scarce, forcing the reexamination of the therapeutic possibilities of β-lactams plus β-lactamase inhibitors (BBLIs). Inhibitor-resistant CTX-M β-lactamases (IR-CTX-M) have not hitherto been described in natural isolates. In this study, 168 cultures of the hypermutagenic Escherichia coli GB20 strain carrying plasmid pBGS18 with different bla(CTX-M) genes were submitted to parallel experimental evolution assays in the presence of increasing concentrations of a combination of amoxicillin and clavulanate. Fourteen CTX-M β-lactamases belonging to the three most representative clusters (CTX-M-1, -2, and -9) and the two main phenotypes (cefotaxime resistance and cefotaxime-ceftazidime resistance) were studied. Three types of IR-CTX-M mutants were detected, having mutations S130G, K234R, and S237G, which are associated with different resistance patterns. The most frequently recovered mutation was S130G, which conferred the highest resistance levels to BBLIs (reaching 12 μg/ml for amoxicillin-clavulanate and 96 μg/ml for piperacillin-tazobactam when acquired by CTX-M-1 cluster enzymes). The S130G change also provided a clear antagonistic pleiotropy effect, strongly decreasing the enzyme's activity against all cephalosporins tested. A double mutation, S130G L169S, partially restored the resistance against cephalosporins. A complex pattern observed in CTX-M-58, carrying P167S and S130G or K234R changes, conferred ESBL and IR phenotypes simultaneously. The K234R and S237G changes had a smaller effect in providing inhibitor resistance. In summary, IR-CTX-M enzymes might evolve under exposure to BBLIs, and the probability is higher for enzymes belonging to the CTX-M-1 cluster. However, this process could be delayed by antagonistic pleiotropy.
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Affiliation(s)
- Aida Ripoll
- Servicio de Microbiología and CIBER en Epidemiología y Salud Pública (CIBERESP), Instituto Ramón y Cajal de Investigación Sanitaria (IRYCIS), Madrid, Spain
| | - Fernando Baquero
- Servicio de Microbiología and CIBER en Epidemiología y Salud Pública (CIBERESP), Instituto Ramón y Cajal de Investigación Sanitaria (IRYCIS), Madrid, Spain
- Unidad de Resistencia a Antibióticos y Virulencia Bacteriana (RYC-CSIC), Madrid, Spain
| | - Ângela Novais
- Servicio de Microbiología and CIBER en Epidemiología y Salud Pública (CIBERESP), Instituto Ramón y Cajal de Investigación Sanitaria (IRYCIS), Madrid, Spain
- REQUIMTE, Laboratório de Microbiologia, Faculdade de Farmácia, Universidade do Porto, Porto, Portugal
| | - Mario J. Rodríguez-Domínguez
- Servicio de Microbiología and CIBER en Epidemiología y Salud Pública (CIBERESP), Instituto Ramón y Cajal de Investigación Sanitaria (IRYCIS), Madrid, Spain
| | - Maria-Carmen Turrientes
- Servicio de Microbiología and CIBER en Epidemiología y Salud Pública (CIBERESP), Instituto Ramón y Cajal de Investigación Sanitaria (IRYCIS), Madrid, Spain
| | - Rafael Cantón
- Servicio de Microbiología and CIBER en Epidemiología y Salud Pública (CIBERESP), Instituto Ramón y Cajal de Investigación Sanitaria (IRYCIS), Madrid, Spain
- Unidad de Resistencia a Antibióticos y Virulencia Bacteriana (RYC-CSIC), Madrid, Spain
| | - Juan-Carlos Galán
- Servicio de Microbiología and CIBER en Epidemiología y Salud Pública (CIBERESP), Instituto Ramón y Cajal de Investigación Sanitaria (IRYCIS), Madrid, Spain
- Unidad de Resistencia a Antibióticos y Virulencia Bacteriana (RYC-CSIC), Madrid, Spain
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Ramdani-Bouguessa N, Manageiro V, Jones-Dias D, Ferreira E, Tazir M, Caniça M. Role of SHV β-lactamase variants in resistance of clinical Klebsiella pneumoniae strains to β-lactams in an Algerian hospital. J Med Microbiol 2011; 60:983-987. [PMID: 21415202 DOI: 10.1099/jmm.0.030577-0] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Three clinical Klebsiella pneumoniae strains, KpARG74, KpARG220 and KpARG185, isolated from a hospital in Algeria, carried the novel β-lactamases SHV-98, SHV-99 and SHV-100, respectively, and co-expressed TEM-1 and either CTX-M-3 or CTX-M-15. In contrast, transformed cells possessing the genes for these novel β-lactamases, i.e. EcDH5α-SHV-98, EcDH5α-SHV-99 and EcDH5α-SHV-100, respectively, carried unique sequence features of bla(SHV) gene variants, enabling oxyimino-cephalosporin susceptibility and confirming that none of the transformants exhibited extended-spectrum β-lactamase (ESBL) properties. SHV-100 is apparently functional, despite differing from the SHV-1 sequence by duplication of 13 amino acids. The SHV-99 enzyme differed from the parental SHV-1 by the amino acid substitution Asp104→Gly, which is an important position in the development of the ESBL phenotype in TEM β-lactamases. This is the first time, to our knowledge, that this mutation has been reported in clinically occurring isolates. Thus, kinetic characterization of the SHV-99 enzyme was performed. The SHV-99 enzyme showed higher affinity (K(m) of 196 µM), catalytic activity (k(cat) of 0.5 s⁻¹) and catalytic efficiency (k(cat)/K(m) of 0.003 µM⁻¹ s⁻¹) than SHV-1 β-lactamase against aztreonam. These results showed that the neutral glycine at residue 104 increased the affinity of the enzyme to aztreonam, but was unable to develop the ESBL phenotype in SHV enzymes. As the emergence of new threatening combinations of resistance determinants among nosocomial pathogens is further possible, this study has highlighted the need to reverse the spread of initial mutations.
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Affiliation(s)
| | - Vera Manageiro
- Laboratory of Antimicrobial Resistance, National Institute of Health Dr Ricardo Jorge, Lisbon, Portugal
| | - Daniela Jones-Dias
- Laboratory of Antimicrobial Resistance, National Institute of Health Dr Ricardo Jorge, Lisbon, Portugal
| | - Eugénia Ferreira
- Laboratory of Antimicrobial Resistance, National Institute of Health Dr Ricardo Jorge, Lisbon, Portugal
| | - Mohamed Tazir
- Service de Microbiologie, Centre Hospitalo-Universitaire Mustapha Pacha, 16000 Algiers, Algeria
| | - Manuela Caniça
- Laboratory of Antimicrobial Resistance, National Institute of Health Dr Ricardo Jorge, Lisbon, Portugal
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18
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Rayamajhi N, Joo JC, Cha SB, Pokherl S, Shin MK, Yoo YJ, Yoo HS. Enzymatic analysis of the effect of naturally occurring Leu138Pro mutation identified in SHV β-lactamase on hydrolysis of penicillin and ampicillin. BMC Microbiol 2011; 11:29. [PMID: 21291571 PMCID: PMC3045869 DOI: 10.1186/1471-2180-11-29] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2010] [Accepted: 02/04/2011] [Indexed: 11/28/2022] Open
Abstract
Background The aim of this study was to analyze the significance of leucine to proline substitution at position 138(Leu138Pro) on the hydrolysis of penicillin and ampicillin that we identified in the blaSHV gene of clinical Escherichia coli swine isolate. Results Kinetic analysis of the mutant proteins showed that Km value of the purified L138P mutant was comparatively higher than SHV-1, SHV-33 and SHV-33(L138P) enzyme for penicillin and ampicillin. Docking simulation of the SHV-1 and SHV-(L138P) enzymes also confirmed that β-lactamases preferred penicillin to ampicillin and the SHV-1 had a higher binding affinity for antibiotics compared to the SHV-(L138P) and other mutants. Conclusions Our result demonstrated that L138P has a reduced role in penicillin and ampicillin hydrolyzing properties of SHV β-lactamases. These naturally occurring mutations rendering reduced function of the existing protein could trigger the emergence or acquisition of more effective alternative mechanisms for β-lactam hydrolysis.
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Affiliation(s)
- Nabin Rayamajhi
- Department of Infectious Diseases, College of Veterinary Medicine, Brain Korea 21 for Veterinary Science, Seoul National University, Seoul, S Korea
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Manageiro V, Ferreira E. Biochemical study of a new inhibitor-resistant beta-lactamase, SHV-84, produced by a clinical Escherichia coli strain. Antimicrob Agents Chemother 2010; 54:2271-2. [PMID: 20211886 PMCID: PMC2863691 DOI: 10.1128/aac.01442-09] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
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Abstract
Since the introduction of penicillin, beta-lactam antibiotics have been the antimicrobial agents of choice. Unfortunately, the efficacy of these life-saving antibiotics is significantly threatened by bacterial beta-lactamases. beta-Lactamases are now responsible for resistance to penicillins, extended-spectrum cephalosporins, monobactams, and carbapenems. In order to overcome beta-lactamase-mediated resistance, beta-lactamase inhibitors (clavulanate, sulbactam, and tazobactam) were introduced into clinical practice. These inhibitors greatly enhance the efficacy of their partner beta-lactams (amoxicillin, ampicillin, piperacillin, and ticarcillin) in the treatment of serious Enterobacteriaceae and penicillin-resistant staphylococcal infections. However, selective pressure from excess antibiotic use accelerated the emergence of resistance to beta-lactam-beta-lactamase inhibitor combinations. Furthermore, the prevalence of clinically relevant beta-lactamases from other classes that are resistant to inhibition is rapidly increasing. There is an urgent need for effective inhibitors that can restore the activity of beta-lactams. Here, we review the catalytic mechanisms of each beta-lactamase class. We then discuss approaches for circumventing beta-lactamase-mediated resistance, including properties and characteristics of mechanism-based inactivators. We next highlight the mechanisms of action and salient clinical and microbiological features of beta-lactamase inhibitors. We also emphasize their therapeutic applications. We close by focusing on novel compounds and the chemical features of these agents that may contribute to a "second generation" of inhibitors. The goal for the next 3 decades will be to design inhibitors that will be effective for more than a single class of beta-lactamases.
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Affiliation(s)
- Sarah M. Drawz
- Departments of Pathology, Medicine, Pharmacology, Molecular Biology and Microbiology, Case Western Reserve University School of Medicine, Cleveland, Ohio, Research Service, Louis Stokes Cleveland Department of Veterans Affairs Medical Center, Cleveland, Ohio
| | - Robert A. Bonomo
- Departments of Pathology, Medicine, Pharmacology, Molecular Biology and Microbiology, Case Western Reserve University School of Medicine, Cleveland, Ohio, Research Service, Louis Stokes Cleveland Department of Veterans Affairs Medical Center, Cleveland, Ohio
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Biochemical characterization of SHV-55, an extended-spectrum class A beta-lactamase from Klebsiella pneumoniae. Antimicrob Agents Chemother 2008; 52:1897-8. [PMID: 18316524 DOI: 10.1128/aac.01525-07] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
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