1
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Canabal R, González-Bello C. Chemical sensors for the early diagnosis of bacterial resistance to β-lactam antibiotics. Bioorg Chem 2024; 150:107528. [PMID: 38852309 DOI: 10.1016/j.bioorg.2024.107528] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2024] [Revised: 05/30/2024] [Accepted: 06/03/2024] [Indexed: 06/11/2024]
Abstract
β-Lactamases are bacterial enzymes that inactivate β-lactam antibiotics and, as such, are the most prevalent cause of antibiotic resistance in Gram-negative bacteria. The ever-increasing production and worldwide dissemination of bacterial strains producing carbapenemases is currently a global health concern. These enzymes catalyze the hydrolysis of carbapenems - the β-lactam antibiotics with the broadest spectrum of activity that are often considered as drugs of last resort. The incidence of carbapenem-resistant pathogens such as Pseudomonas aeruginosa, Acinetobacter baumannii and carbapenemase or extended spectrum beta-lactamase (ESBL)-producing Enterobacterales, which are frequent in clinical settings, is worrisome since, in some cases, no therapies are available. These include all metallo-β-lactamases (VIM, IMP, NDM, SMP, and L1), and serine-carbapenemases of classes A (KPC, SME, IMI, and GES), and of classes D (OXA-23, OXA-24/40, OXA-48 and OXA-58). Consequently, the early diagnosis of bacterial strains harboring carbapenemases is a pivotal task in clinical microbiology in order to track antibiotic bacterial resistance and to improve the worldwide management of infectious diseases. Recent research efforts on the development of chromogenic and fluorescent chemical sensors for the specific and sensitive detection and quantification of β-lactamase production in multidrug-resistant pathogens are summarized herein. Studies to circumvent the main limitations of the phenotypic and molecular methods are discussed. Recently reported chromogenic and fluorogenic cephalosporin- and carbapenem-based β-lactamase substrates will be reviewed as alternative options to the currently available nitrocefin and related compounds, a chromogenic cephalosporin-based reagent widely used in clinical microbiology laboratories. The scope of these new chemical sensors, along with the synthetic approaches to synthesize them, is also summarized.
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Affiliation(s)
- Rafael Canabal
- Centro Singular de Investigación en Química Biolóxica e Materiais Moleculares (CiQUS), Departamento de Química Orgánica, Universidade de Santiago de Compostela, Jenaro de la Fuente s/n, 15782 Santiago de Compostela, Spain
| | - Concepción González-Bello
- Centro Singular de Investigación en Química Biolóxica e Materiais Moleculares (CiQUS), Departamento de Química Orgánica, Universidade de Santiago de Compostela, Jenaro de la Fuente s/n, 15782 Santiago de Compostela, Spain.
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2
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Rima M, Oueslati S, Cotelon G, Creton E, Bonnin RA, Dortet L, Iorga BI, Naas T. Role of amino acid 159 in carbapenem and temocillin hydrolysis of OXA-933, a novel OXA-48 variant. Antimicrob Agents Chemother 2024; 68:e0018024. [PMID: 38526049 PMCID: PMC11064584 DOI: 10.1128/aac.00180-24] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2024] [Accepted: 02/26/2024] [Indexed: 03/26/2024] Open
Abstract
OXA-48 has rapidly disseminated worldwide and become one of the most common carbapenemases in many countries with more than 45 variants reported with, in some cases, significant differences in their hydrolysis profiles. The R214 residue, located in the ß5-ß6 loop, is crucial for the carbapenemase activity, as it stabilizes carbapenems in the active site and maintains the shape of the active site through interactions with D159. In this study, we have characterized a novel variant of OXA-48, OXA-933 with a single D159N change. To evaluate the importance of this residue, point mutations were generated (D159A, D159G, D159K, and D159W), kinetic parameters of OXA-933, OXA-48 D159G, and OXA-48 D159K were determined and compared to those of OXA-48 and OXA-244. The blaOXA-933 gene was borne on Tn2208, a 2,696-bp composite transposon made of two IS1 elements surrounded by 9 bp target site duplications and inserted into a non-self-transmissible plasmid pOXA-933 of 7,872 bp in size. Minimal inhibitory concentration values of E. coli expressing the blaOXA-933 gene or of its point mutant derivatives were lower for carbapenems (except for D159G) as compared to those expressing the blaOXA-48 gene. Steady-state kinetic parameters revealed lower catalytic efficiencies for expanded spectrum cephalosporins and carbapenems. A detailed structural analysis confirmed the crucial role of D159 in shaping the active site of OXA-48 enzymes by interacting with R214. Our work further illustrates the remarkable propensity of OXA-48-like carbapenemases to evolve through mutations at positions outside the β5-β6 loop, but interacting with key residues of it.
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Affiliation(s)
- Mariam Rima
- Team ReSIST, INSERM U1184, School of Medicine Université Paris-Saclay, LabEx LERMIT, Le Kremlin-Bicêtre, France
| | - Saoussen Oueslati
- Team ReSIST, INSERM U1184, School of Medicine Université Paris-Saclay, LabEx LERMIT, Le Kremlin-Bicêtre, France
- Bacteriology-Hygiene Unit, Assistance Publique/Hôpitaux de Paris, Bicêtre Hospital, Le Kremlin-Bicêtre, France
| | - Garance Cotelon
- French National Reference Center for Antibiotic Resistance: Carbapenemase-Producing Enterobacterales, Le Kremlin-Bicêtre, France
| | - Elodie Creton
- French National Reference Center for Antibiotic Resistance: Carbapenemase-Producing Enterobacterales, Le Kremlin-Bicêtre, France
| | - Rémy A. Bonnin
- Team ReSIST, INSERM U1184, School of Medicine Université Paris-Saclay, LabEx LERMIT, Le Kremlin-Bicêtre, France
- French National Reference Center for Antibiotic Resistance: Carbapenemase-Producing Enterobacterales, Le Kremlin-Bicêtre, France
| | - Laurent Dortet
- Team ReSIST, INSERM U1184, School of Medicine Université Paris-Saclay, LabEx LERMIT, Le Kremlin-Bicêtre, France
- Bacteriology-Hygiene Unit, Assistance Publique/Hôpitaux de Paris, Bicêtre Hospital, Le Kremlin-Bicêtre, France
- French National Reference Center for Antibiotic Resistance: Carbapenemase-Producing Enterobacterales, Le Kremlin-Bicêtre, France
| | - Bogdan I. Iorga
- Université Paris-Saclay, CNRS UPR 2301, Institut de Chimie des Substances Naturelles, Gif-sur-Yvette, France
| | - Thierry Naas
- Team ReSIST, INSERM U1184, School of Medicine Université Paris-Saclay, LabEx LERMIT, Le Kremlin-Bicêtre, France
- Bacteriology-Hygiene Unit, Assistance Publique/Hôpitaux de Paris, Bicêtre Hospital, Le Kremlin-Bicêtre, France
- French National Reference Center for Antibiotic Resistance: Carbapenemase-Producing Enterobacterales, Le Kremlin-Bicêtre, France
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3
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Zhou Q, Catalán P, Bell H, Baumann P, Cooke R, Evans R, Yang J, Zhang Z, Zappalà D, Zhang Y, Blackburn GM, He Y, Jin Y. An Ion-Pair Induced Intermediate Complex Captured in Class D Carbapenemase Reveals Chloride Ion as a Janus Effector Modulating Activity. ACS CENTRAL SCIENCE 2023; 9:2339-2349. [PMID: 38161376 PMCID: PMC10755735 DOI: 10.1021/acscentsci.3c00609] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/17/2023] [Revised: 11/17/2023] [Accepted: 11/17/2023] [Indexed: 01/03/2024]
Abstract
Antibiotic-resistant Enterobacterales that produce oxacillinase (OXA)-48-like Class D β-lactamases are often linked to increased clinical mortality. Though the catalytic mechanism of OXA-48 is known, the molecular origin of its biphasic kinetics has been elusive. We here identify selective chloride binding rather than decarbamylation of the carbamylated lysine as the source of biphasic kinetics, utilizing isothermal titration calorimetry (ITC) to monitor the complete reaction course with the OXA-48 variant having a chemically stable N-acetyl lysine. Further structural investigation enables us to capture an unprecedented inactive acyl intermediate wedged in place by a halide ion paired with a conserved active site arginine. Supported by mutagenesis and mathematical simulation, we identify chloride as a "Janus effector" that operates by allosteric activation of the burst phase and by inhibition of the steady state in kinetic assays of β-lactams. We show that chloride-induced biphasic kinetics directly affects antibiotic efficacy and facilitates the differentiation of clinical isolates encoding Class D from Class A and B carbapenemases. As chloride is present in laboratory and clinical procedures, our discovery greatly expands the roles of chloride in modulating enzyme catalysis and highlights its potential impact on the pharmacokinetics and efficacy of antibiotics during in vivo treatment.
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Affiliation(s)
- Qi Zhou
- Key
Laboratory of Synthetic and Natural Functional Molecule, College of
Chemistry and Materials Science, Northwest
University, Xi’an 710127, P. R. China
| | - Pablo Catalán
- Grupo
Interdisciplinar de Sistemas Complejos, Departamento de Matemáticas, Universidad Carlos III de Madrid, 28911 Leganés, Spain
| | - Helen Bell
- School
of Chemistry, Cardiff University, Cardiff, CF10 3AT, United Kingdom
| | - Patrick Baumann
- School
of Chemistry, Cardiff University, Cardiff, CF10 3AT, United Kingdom
- Manchester
Institute of Biotechnology, University of
Manchester, 131 Princess Street, Manchester M1 7DN, United Kingdom
| | - Rebekah Cooke
- School
of Chemistry, Cardiff University, Cardiff, CF10 3AT, United Kingdom
| | - Rhodri Evans
- School
of Chemistry, Cardiff University, Cardiff, CF10 3AT, United Kingdom
- Manchester
Institute of Biotechnology, University of
Manchester, 131 Princess Street, Manchester M1 7DN, United Kingdom
| | - Jianhua Yang
- Key
Laboratory of Synthetic and Natural Functional Molecule, College of
Chemistry and Materials Science, Northwest
University, Xi’an 710127, P. R. China
| | - Zhen Zhang
- Key
Laboratory of Synthetic and Natural Functional Molecule, College of
Chemistry and Materials Science, Northwest
University, Xi’an 710127, P. R. China
- School
of Chemistry, Cardiff University, Cardiff, CF10 3AT, United Kingdom
| | - Davide Zappalà
- School
of Chemistry, Cardiff University, Cardiff, CF10 3AT, United Kingdom
| | - Ye Zhang
- Key
Laboratory of Synthetic and Natural Functional Molecule, College of
Chemistry and Materials Science, Northwest
University, Xi’an 710127, P. R. China
| | - George Michael Blackburn
- School
of Biosciences, University of Sheffield, Firth Court, Western Bank, Sheffield S10 2TN, United Kingdom
| | - Yuan He
- Key
Laboratory of Synthetic and Natural Functional Molecule, College of
Chemistry and Materials Science, Northwest
University, Xi’an 710127, P. R. China
| | - Yi Jin
- School
of Chemistry, Cardiff University, Cardiff, CF10 3AT, United Kingdom
- Manchester
Institute of Biotechnology, University of
Manchester, 131 Princess Street, Manchester M1 7DN, United Kingdom
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4
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Jain D, Verma J, Ajith T, Bhattacharjee A, Ghosh AS. Two non-active site residues W165 and L166 prominently influence the beta-lactam hydrolytic ability of OXA-23 beta-lactamase. J Antibiot (Tokyo) 2023; 76:489-498. [PMID: 37095236 DOI: 10.1038/s41429-023-00624-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2023] [Revised: 03/28/2023] [Accepted: 04/02/2023] [Indexed: 04/26/2023]
Abstract
Dissemination of class D OXA-type carbapenemases is one of the significant causes of beta-lactam resistance in Gram-negative bacteria. The amino acid residues present near the active site are involved in hydrolytic mechanism of class D carbapenemases, though it is not identified in OXA-23. Here, with the help of site-directed mutagenesis, we aimed to explicate the importance of the residues W165, L166 and V167 of the possible omega loop and residue D222 in the short β5-β6 loop on the activity of OXA-23. All the residues were substituted with alanine. The resultant proteins were assayed for the changes in activity in E. coli cells and purified for in vitro activity, and stability assessment. E. coli cells harboring OXA-23_W165A and OXA-23_L166A, individually, exhibited a significant decrease in resistance towards beta-lactam antibiotics as compared to OXA-23. Further, purified OXA-23_W165A and OXA-23_L166A imparted about >4-fold decrease in catalytic efficiency and displayed reduced thermal stability as compared to OXA-23. Bocillin-FL binding assay revealed that W165A substitution results in improper N-carboxylation of K82, leading to deacylation deficient OXA-23. Therefore, we infer that the residue W165 maintains the integrity of N-carboxylated lysine (K82) of OXA-23 and the residue L166 might be responsible for properly orientating the antibiotic molecules.
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Affiliation(s)
- Diamond Jain
- Department of Biotechnology, Indian Institute of Technology Kharagpur, Kharagpur, 721302, West Bengal, India
| | - Jyoti Verma
- Advanced Technology Development Centre, Indian Institute of Technology Kharagpur, Kharagpur, 721302, West Bengal, India
| | - Tejavath Ajith
- Department of Biotechnology, Indian Institute of Technology Kharagpur, Kharagpur, 721302, West Bengal, India
| | | | - Anindya Sundar Ghosh
- Department of Biotechnology, Indian Institute of Technology Kharagpur, Kharagpur, 721302, West Bengal, India.
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5
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Smith CA, Stewart NK, Toth M, Quan P, Buynak JD, Vakulenko SB. The C5α-Methyl-Substituted Carbapenem NA-1-157 Exhibits Potent Activity against Klebsiella spp. Isolates Producing OXA-48-Type Carbapenemases. ACS Infect Dis 2023; 9:1123-1136. [PMID: 37130087 PMCID: PMC10722881 DOI: 10.1021/acsinfecdis.3c00059] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
The wide spread of carbapenem-hydrolyzing β-lactamases in Gram-negative bacteria has diminished the utility of the last-resort carbapenem antibiotics, significantly narrowing the available therapeutic options. In the Enterobacteriaceae family, which includes many important clinical pathogens such as Klebsiella pneumoniae and Escherichia coli, production of class D β-lactamases from the OXA-48-type family constitutes the major mechanism of resistance to carbapenems. To address the public health threat posed by these enzymes, novel, effective therapeutics are urgently needed. Here, we report evaluation of a novel, C5α-methyl-substituted carbapenem, NA-1-157, and show that its MICs against bacteria producing OXA-48-type enzymes were reduced by 4- to 32-fold when compared to meropenem. When combined with commercial carbapenems, the potency of NA-1-157 was further enhanced, resulting in target potentiation concentrations ranging from 0.125 to 2 μg/mL. Kinetic studies demonstrated that the compound is poorly hydrolyzed by OXA-48, with a catalytic efficiency 30- to 50-fold lower than those of imipenem and meropenem. Acylation of OXA-48 by NA-1-157 was severely impaired, with a rate 10,000- to 36,000-fold slower when compared to the commercial carbapenems. Docking, molecular dynamics, and structural studies demonstrated that the presence of the C5α-methyl group in NA-1-157 creates steric clashes within the active site, leading to differences in the position and the hydrogen-bonding pattern of the compound, which are incompatible with efficient acylation. This study demonstrates that NA-1-157 is a promising novel carbapenem for treatment of infections caused by OXA-48-producing bacterial pathogens.
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Affiliation(s)
- Clyde A Smith
- Stanford Synchrotron Radiation Lightsource, Stanford University, Menlo Park, California 94025, United States
- Department of Chemistry, Stanford University, Stanford, California 94305, United States
| | - Nichole K Stewart
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, Indiana 46556, United States
| | - Marta Toth
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, Indiana 46556, United States
| | - Pojun Quan
- Department of Chemistry, Southern Methodist University, Dallas, Texas 75275, United States
| | - John D Buynak
- Department of Chemistry, Southern Methodist University, Dallas, Texas 75275, United States
| | - Sergei B Vakulenko
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, Indiana 46556, United States
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6
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Structural and Biochemical Features of OXA-517: a Carbapenem and Expanded-Spectrum Cephalosporin Hydrolyzing OXA-48 Variant. Antimicrob Agents Chemother 2023; 67:e0109522. [PMID: 36648230 PMCID: PMC9933634 DOI: 10.1128/aac.01095-22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
Abstract
OXA-48-producing Enterobacterales have now widely disseminated throughout the world. Several variants have now been reported, differing by just a few amino-acid substitutions or deletions, mostly in the region of the loop β5-β6. As OXA-48 hydrolyzes carbapenems but lacks significant expanded-spectrum cephalosporin (ESC) hydrolytic activity, ESCs were suggested as a therapeutic option. Here, we have characterized OXA-517, a natural variant of OXA-48- with an Arg214Lys substitution and a deletion of Ile215 and Glu216 in the β5-β6 loop, capable of hydrolyzing at the same time ESC and carbapenems. MICs values of E. coli expressing blaOXA-517 gene revealed reduced susceptibility to carbapenems (similarly to OXA-48) and resistance to ESCs. Steady-state kinetic parameters revealed high catalytic efficiencies for ESCs and carbapenems. The blaOXA-517 gene was located on a ca. 31-kb plasmid identical to the prototypical IncL blaOXA-48-carrying plasmid except for an IS1R-mediated deletion of 30.7-kb in the tra operon. The crystal structure of OXA-517, determined to 1.86 Å resolution, revealed an expanded active site compared to that of OXA-48, which allows for accommodation of the bulky ceftazidime substrate. Our work illustrates the remarkable propensity of OXA-48-like carbapenemases to evolve through mutation/deletion in the β5-β6 loop to extend its hydrolysis profile to encompass most β-lactam substrates.
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7
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Avci FG, Tastekil I, Jaisi A, Ozbek Sarica P, Sariyar Akbulut B. A review on the mechanistic details of OXA enzymes of ESKAPE pathogens. Pathog Glob Health 2022; 117:219-234. [PMID: 35758005 PMCID: PMC10081068 DOI: 10.1080/20477724.2022.2088496] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022] Open
Abstract
The production of β-lactamases is a prevalent mechanism that poses serious pressure on the control of bacterial resistance. Furthermore, the unavoidable and alarming increase in the transmission of bacteria producing extended-spectrum β-lactamases complicates treatment alternatives with existing drugs and/or approaches. Class D β-lactamases, designated as OXA enzymes, are characterized by their activity specifically towards oxacillins. They are widely distributed among the ESKAPE bugs that are associated with antibiotic resistance and life-threatening hospital infections. The inadequacy of current β-lactamase inhibitors for conventional treatments of 'OXA' mediated infections confirms the necessity of new approaches. Here, the focus is on the mechanistic details of OXA-10, OXA-23, and OXA-48, commonly found in highly virulent and antibiotic-resistant pathogens Acinetobacter baumannii, Klebsiella pneumoniae, Pseudomonas aeruginosa, and Enterobacter spp. to describe their similarities and differences. Furthermore, this review contains a specific emphasis on structural and computational perspectives, which will be valuable to guide efforts in the design/discovery of a common single-molecule drug against ESKAPE pathogens.
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Affiliation(s)
- Fatma Gizem Avci
- Bioengineering Department, Uskudar University, Uskudar, 34662, Turkey
| | - Ilgaz Tastekil
- Bioengineering Department, Marmara University, Kadikoy, 34722, Turkey
| | - Amit Jaisi
- Drug and Cosmetics Excellence Center, School of Pharmacy, Walailak University, 80160, Nakhon Si Thammarat, Thailand
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8
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Kim HR, Eom YB. Auranofin promotes antibacterial effect of doripenem against carbapenem-resistant Acinetobacter baumannii. J Appl Microbiol 2022; 133:1422-1433. [PMID: 35633297 DOI: 10.1111/jam.15644] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2021] [Revised: 03/10/2022] [Accepted: 05/25/2022] [Indexed: 11/29/2022]
Abstract
AIMS This study was performed to identify the potential for repurposing auranofin as an antibiotic adjuvant against carbapenemase-producing A. baumannii. METHODS AND RESULTS The clinically isolated A. baumannii strains used in this study were all resistant to carbapenems and harbored the blaOXA-23 gene. The synergistic effect of auranofin and doripenem against carbapenemase-producing A. baumannii was confirmed through checkerboard and growth kinetic analyses. This study also demonstrated the inhibitory effects of auranofin against A. baumannii biofilms. The anti-biofilm effects of auranofin were visualized by confocal laser scanning microscopy (CLSM). Furthermore, auranofin inhibited motility, one of the virulence factors. Additionally, the changes in the expression of carbapenemase-, biofilm- and efflux pump-related genes induced by auranofin were confirmed via quantitative polymerase chain reaction (qPCR). CONCLUSIONS Our results demonstrated that auranofin has an antibacterial effect with doripenem and an inhibitory effect on several factors related to carbapenem resistance. SIGNIFICANCE AND IMPACT OF THE STUDY This study suggests that auranofin is a promising antibiotic adjuvant that can be used to prevent antibiotic resistance in carbapenem-resistant A. baumannii.
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Affiliation(s)
- H-R Kim
- Department of Medical Sciences, Graduate School, Soonchunhyang University, Asan, Chungnam 31538, Republic of Korea
| | - Y-B Eom
- Department of Medical Sciences, Graduate School, Soonchunhyang University, Asan, Chungnam 31538, Republic of Korea.,Department of Biomedical Laboratory Science, College of Medical Sciences, Soonchunhyang University, Asan, Chungnam 31538, Republic of Korea
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9
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Hirvonen VA, Weizmann TM, Mulholland AJ, Spencer J, van der Kamp MW. Multiscale Simulations Identify Origins of Differential Carbapenem Hydrolysis by the OXA-48 β-Lactamase. ACS Catal 2022; 12:4534-4544. [PMID: 35571461 PMCID: PMC9097296 DOI: 10.1021/acscatal.1c05694] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2021] [Revised: 03/22/2022] [Indexed: 12/27/2022]
Abstract
OXA-48 β-lactamases are frequently encountered in bacterial infections caused by carbapenem-resistant Gram-negative bacteria. Due to the importance of carbapenems in the treatment of healthcare-associated infections and the increasingly wide dissemination of OXA-48-like enzymes on plasmids, these β-lactamases are of high clinical significance. Notably, OXA-48 hydrolyzes imipenem more efficiently than other commonly used carbapenems, such as meropenem. Here, we use extensive multiscale simulations of imipenem and meropenem hydrolysis by OXA-48 to dissect the dynamics and to explore differences in the reactivity of the possible conformational substates of the respective acylenzymes. Quantum mechanics/molecular mechanics (QM/MM) simulations of the deacylation reaction for both substrates demonstrate that deacylation is favored when the 6α-hydroxyethyl group is able to hydrogen bond to the water molecule responsible for deacylation but disfavored by the increasing hydration of either oxygen of the carboxylated Lys73 general base. Differences in free energy barriers calculated from the QM/MM simulations correlate well with the experimentally observed differences in hydrolytic efficiency between meropenem and imipenem. We conclude that the impaired breakdown of meropenem, compared to imipenem, which arises from a subtle change in the hydrogen bonding pattern between the deacylating water molecule and the antibiotic, is most likely induced by the meropenem 1β-methyl group. In addition to increased insights into carbapenem breakdown by OXA β-lactamases, which may aid in future efforts to design antibiotics or inhibitors, our approach exemplifies the combined use of atomistic simulations in determining the possible different enzyme-substrate substates and their influence on enzyme reaction kinetics.
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Affiliation(s)
- Viivi
H. A. Hirvonen
- School
of Biochemistry, University of Bristol, University Walk, Bristol BS8 1TD, U.K.
- Centre
for Computational Chemistry, School of Chemistry, University of Bristol, Cantock’s Close, Bristol BS8 1TS, U.K.
| | - Tal Moshe Weizmann
- School
of Biochemistry, University of Bristol, University Walk, Bristol BS8 1TD, U.K.
| | - Adrian J. Mulholland
- Centre
for Computational Chemistry, School of Chemistry, University of Bristol, Cantock’s Close, Bristol BS8 1TS, U.K.
| | - James Spencer
- School
of Cellular and Molecular Medicine, University
of Bristol, University
Walk, Bristol BS8 1TD, U.K.
| | - Marc W. van der Kamp
- School
of Biochemistry, University of Bristol, University Walk, Bristol BS8 1TD, U.K.
- Centre
for Computational Chemistry, School of Chemistry, University of Bristol, Cantock’s Close, Bristol BS8 1TS, U.K.
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10
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C6 Hydroxymethyl-Substituted Carbapenem MA-1-206 Inhibits the Major Acinetobacter baumannii Carbapenemase OXA-23 by Impeding Deacylation. mBio 2022; 13:e0036722. [PMID: 35420470 PMCID: PMC9239083 DOI: 10.1128/mbio.00367-22] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
Acinetobacter baumannii has become a major nosocomial pathogen, as it is often multidrug-resistant, which results in infections characterized by high mortality rates. The bacterium achieves high levels of resistance to β-lactam antibiotics by producing β-lactamases, enzymes which destroy these valuable agents. Historically, the carbapenem family of β-lactam antibiotics have been the drugs of choice for treating A. baumannii infections. However, their effectiveness has been significantly diminished due to the pathogen’s production of carbapenem-hydrolyzing class D β-lactamases (CHDLs); thus, new antibiotics and inhibitors of these enzymes are urgently needed. Here, we describe a new carbapenem antibiotic, MA-1-206, in which the canonical C6 hydroxyethyl group has been replaced with hydroxymethyl. The antimicrobial susceptibility studies presented here demonstrated that this compound is more potent than meropenem and imipenem against A. baumannii producing OXA-23, the most prevalent CHDL of this pathogen, and also against strains producing the CHDL OXA-24/40 and the class B metallo-β-lactamase VIM-2. Our kinetic and mass spectrometry studies revealed that this drug is a reversible inhibitor of OXA-23, where inhibition takes place through a branched pathway. X-ray crystallographic studies, molecular docking, and molecular dynamics simulations of the OXA-23-MA-1-206 complex show that the C6 hydroxymethyl group forms a hydrogen bond with the carboxylated catalytic lysine of OXA-23, effectively preventing deacylation. These results provide a promising strategy for designing a new generation of CHDL-resistant carbapenems to restore their efficacy against deadly A. baumannii infections.
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11
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Chiou J, Cheng Q, Shum PTF, Wong MHY, Chan EWC, Chen S. Structural and Functional Characterization of OXA-48: Insight into Mechanism and Structural Basis of Substrate Recognition and Specificity. Int J Mol Sci 2021; 22:ijms222111480. [PMID: 34768916 PMCID: PMC8583920 DOI: 10.3390/ijms222111480] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2021] [Revised: 10/10/2021] [Accepted: 10/21/2021] [Indexed: 02/04/2023] Open
Abstract
Class D β-lactamase OXA-48 is widely distributed among Gram-negative bacteria and is an important determinant of resistance to the last-resort carbapenems. Nevertheless, the detailed mechanism by which this β-lactamase hydrolyzes its substrates remains poorly understood. In this study, the complex structures of OXA-48 and various β-lactams were modeled and the potential active site residues that may interact with various β-lactams were identified and characterized to elucidate their roles in OXA-48 substrate recognition. Four residues, namely S70, K73, S118, and K208 were found to be essential for OXA-48 to undergo catalytic hydrolysis of various penicillins and carbapenems both in vivo and in vitro. T209 was found to be important for hydrolysis of imipenem, whereas R250 played a major role in hydrolyzing ampicillin, imipenem, and meropenem most likely by forming a H-bond or salt-bridge between the side chain of these two residues and the carboxylate oxygen ions of the substrates. Analysis of the effect of substitution of alanine in two residues, W105 and L158, revealed their roles in mediating the activity of OXA-48. Our data show that these residues most likely undergo hydrophobic interaction with the R groups and the core structure of the β-lactam ring in penicillins and the carbapenems, respectively. Unlike OXA-58, mass spectrometry suggested a loss of the C6-hydroxyethyl group during hydrolysis of meropenem by OXA-48, which has never been demonstrated in Class D carbapenemases. Findings in this study provide comprehensive knowledge of the mechanism of the substrate recognition and catalysis of OXA-type β-lactamases.
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Affiliation(s)
- Jiachi Chiou
- State Key Laboratory of Chiroscience, Department of Applied Biology and Chemical Technology, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong, China; (J.C.); (Q.C.); (P.T.-f.S.); (M.H.-y.W.); (E.W.-c.C.)
| | - Qipeng Cheng
- State Key Laboratory of Chiroscience, Department of Applied Biology and Chemical Technology, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong, China; (J.C.); (Q.C.); (P.T.-f.S.); (M.H.-y.W.); (E.W.-c.C.)
- Department of Infectious Diseases and Public Health, Jockey Club College of Veterinary Medicine and Life Sciences, City University of Hong Kong, Kowloon, Hong Kong, China
| | - Perry Tim-fat Shum
- State Key Laboratory of Chiroscience, Department of Applied Biology and Chemical Technology, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong, China; (J.C.); (Q.C.); (P.T.-f.S.); (M.H.-y.W.); (E.W.-c.C.)
| | - Marcus Ho-yin Wong
- State Key Laboratory of Chiroscience, Department of Applied Biology and Chemical Technology, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong, China; (J.C.); (Q.C.); (P.T.-f.S.); (M.H.-y.W.); (E.W.-c.C.)
| | - Edward Wai-chi Chan
- State Key Laboratory of Chiroscience, Department of Applied Biology and Chemical Technology, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong, China; (J.C.); (Q.C.); (P.T.-f.S.); (M.H.-y.W.); (E.W.-c.C.)
| | - Sheng Chen
- Department of Infectious Diseases and Public Health, Jockey Club College of Veterinary Medicine and Life Sciences, City University of Hong Kong, Kowloon, Hong Kong, China
- Correspondence:
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12
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Mora-Ochomogo M, Lohans CT. β-Lactam antibiotic targets and resistance mechanisms: from covalent inhibitors to substrates. RSC Med Chem 2021; 12:1623-1639. [PMID: 34778765 PMCID: PMC8528271 DOI: 10.1039/d1md00200g] [Citation(s) in RCA: 41] [Impact Index Per Article: 13.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2021] [Accepted: 07/25/2021] [Indexed: 12/24/2022] Open
Abstract
The β-lactams are the most widely used antibacterial agents worldwide. These antibiotics, a group that includes the penicillins and cephalosporins, are covalent inhibitors that target bacterial penicillin-binding proteins and disrupt peptidoglycan synthesis. Bacteria can achieve resistance to β-lactams in several ways, including the production of serine β-lactamase enzymes. While β-lactams also covalently interact with serine β-lactamases, these enzymes are capable of deacylating this complex, treating the antibiotic as a substrate. In this tutorial-style review, we provide an overview of the β-lactam antibiotics, focusing on their covalent interactions with their target proteins and resistance mechanisms. We begin by describing the structurally diverse range of β-lactam antibiotics and β-lactamase inhibitors that are currently used as therapeutics. Then, we introduce the penicillin-binding proteins, describing their functions and structures, and highlighting their interactions with β-lactam antibiotics. We next describe the classes of serine β-lactamases, exploring some of the mechanisms by which they achieve the ability to degrade β-lactams. Finally, we introduce the l,d-transpeptidases, a group of bacterial enzymes involved in peptidoglycan synthesis which are also targeted by β-lactam antibiotics. Although resistance mechanisms are now prevalent for all antibiotics in this class, past successes in antibiotic development have at least delayed this onset of resistance. The β-lactams continue to be an essential tool for the treatment of infectious disease, and recent advances (e.g., β-lactamase inhibitor development) will continue to support their future use.
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Affiliation(s)
| | - Christopher T Lohans
- Department of Biomedical and Molecular Sciences, Queen's University Kingston ON K7L 3N6 Canada
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13
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Extended Spectrum Beta-Lactamase (ESBL) Produced by Gram-Negative Bacteria in Trinidad and Tobago. Int J Microbiol 2021; 2021:5582755. [PMID: 34475957 PMCID: PMC8408010 DOI: 10.1155/2021/5582755] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2021] [Accepted: 08/11/2021] [Indexed: 12/13/2022] Open
Abstract
Gram-negative bacterial infections are a global health problem. The production of beta-lactamase is still the most vital factor leading to beta-lactam resistance. In Trinidad and Tobago, extended spectrum beta-lactamase (ESBL) production has been detected and reported mainly in the isolates of Klebsiella pneumoniae and Escherichia coli and constitutes a public health emergency that causes high morbidity and mortality in some patients. In this literature review, the authors cover vast information on ESBL frequency and laboratory detection using both conventional and molecular methods from clinical data. The aim is to make the reader reflect on how the actual knowledge can be used for rapid detection and understanding of the spread of antimicrobial resistance problems stemming from ESBL production among common Gram-negative organisms in the health care system.
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14
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Lund BA, Thomassen AM, Carlsen TJW, Leiros HKS. Biochemical and biophysical characterization of the OXA-48-like carbapenemase OXA-436. Acta Crystallogr F Struct Biol Commun 2021; 77:312-318. [PMID: 34473108 PMCID: PMC8411929 DOI: 10.1107/s2053230x21008645] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2021] [Accepted: 08/18/2021] [Indexed: 11/08/2023] Open
Abstract
The crystal structure of the class D β-lactamase OXA-436 was solved to a resolution of 1.80 Å. Higher catalytic rates were found at higher temperatures for the clinically important antibiotic imipenem, indicating better adaptation of OXA-436 to its mesophilic host than OXA-48, which is believed to originate from an environmental source. Furthermore, based on the most populated conformations during 100 ns molecular-dynamics simulations, it is postulated that the modulation of activity involves conformational shifts of the α3-α4 and β5-β6 loops. While these changes overall do not cause clinically significant shifts in the resistance profile, they show that antibiotic-resistance enzymes exist in a continuum. It is believed that these seemingly neutral differences in the sequence exist on a path leading to significant changes in substrate selectivity.
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Affiliation(s)
- Bjarte Aarmo Lund
- The Norwegian Structural Biology Centre (NorStruct), Department of Chemistry, UiT The Arctic University of Norway, 9037 Tromsø, Norway
- Hylleraas Centre for Quantum Molecular Sciences, Department of Chemistry, UiT The Arctic University of Norway, 9037 Tromsø, Norway
| | - Ane Molden Thomassen
- The Norwegian Structural Biology Centre (NorStruct), Department of Chemistry, UiT The Arctic University of Norway, 9037 Tromsø, Norway
| | - Trine Josefine Warg Carlsen
- The Norwegian Structural Biology Centre (NorStruct), Department of Chemistry, UiT The Arctic University of Norway, 9037 Tromsø, Norway
| | - Hanna-Kirsti Schrøder Leiros
- The Norwegian Structural Biology Centre (NorStruct), Department of Chemistry, UiT The Arctic University of Norway, 9037 Tromsø, Norway
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15
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Xiao YC, Chen XP, Deng J, Yan YH, Zhu KR, Li G, Yu JL, Brem J, Chen F, Schofield CJ, Li GB. Design and enantioselective synthesis of 3-(α-acrylic acid) benzoxaboroles to combat carbapenemase resistance. Chem Commun (Camb) 2021; 57:7709-7712. [PMID: 34259249 PMCID: PMC8330636 DOI: 10.1039/d1cc03026d] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2021] [Accepted: 06/17/2021] [Indexed: 11/21/2022]
Abstract
Chiral 3-substituted benzoxaboroles were designed as carbapenemase inhibitors and efficiently synthesised via asymmetric Morita-Baylis-Hillman reaction. Some of the benzoxaboroles were potent inhibitors of clinically relevant carbapenemases and restored the activity of meropenem in bacteria harbouring these enzymes. Crystallographic analyses validate the proposed mechanism of binding to carbapenemases, i.e. in a manner relating to their antibiotic substrates. The results illustrate how combining a structure-based design approach with asymmetric catalysis can efficiently lead to potent β-lactamase inhibitors and provide a starting point to develop drugs combatting carbapenemases.
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Affiliation(s)
- You-Cai Xiao
- Key Laboratory of Drug-Targeting and Drug Delivery System of the Ministry of Education and Sichuan Research Center for Drug Precision Industrial Technology, West China School of Pharmacy, Sichuan University, Chengdu 610041, China.
| | - Xiao-Pan Chen
- Key Laboratory of Drug-Targeting and Drug Delivery System of the Ministry of Education and Sichuan Research Center for Drug Precision Industrial Technology, West China School of Pharmacy, Sichuan University, Chengdu 610041, China.
| | - Ji Deng
- Key Laboratory of Drug-Targeting and Drug Delivery System of the Ministry of Education and Sichuan Research Center for Drug Precision Industrial Technology, West China School of Pharmacy, Sichuan University, Chengdu 610041, China.
| | - Yu-Hang Yan
- Key Laboratory of Drug-Targeting and Drug Delivery System of the Ministry of Education and Sichuan Research Center for Drug Precision Industrial Technology, West China School of Pharmacy, Sichuan University, Chengdu 610041, China.
| | - Kai-Rong Zhu
- Key Laboratory of Drug-Targeting and Drug Delivery System of the Ministry of Education and Sichuan Research Center for Drug Precision Industrial Technology, West China School of Pharmacy, Sichuan University, Chengdu 610041, China.
| | - Gen Li
- Key Laboratory of Drug-Targeting and Drug Delivery System of the Ministry of Education and Sichuan Research Center for Drug Precision Industrial Technology, West China School of Pharmacy, Sichuan University, Chengdu 610041, China.
| | - Jun-Lin Yu
- Key Laboratory of Drug-Targeting and Drug Delivery System of the Ministry of Education and Sichuan Research Center for Drug Precision Industrial Technology, West China School of Pharmacy, Sichuan University, Chengdu 610041, China.
| | - Jürgen Brem
- Department of Chemistry and the Ineos Oxford Institute for Antimicrobial Research, University of Oxford, 12 Mansfield Road, Oxford, OX1 3TA, UK.
| | - Fener Chen
- Key Laboratory of Drug-Targeting and Drug Delivery System of the Ministry of Education and Sichuan Research Center for Drug Precision Industrial Technology, West China School of Pharmacy, Sichuan University, Chengdu 610041, China.
| | - Christopher J Schofield
- Department of Chemistry and the Ineos Oxford Institute for Antimicrobial Research, University of Oxford, 12 Mansfield Road, Oxford, OX1 3TA, UK.
| | - Guo-Bo Li
- Key Laboratory of Drug-Targeting and Drug Delivery System of the Ministry of Education and Sichuan Research Center for Drug Precision Industrial Technology, West China School of Pharmacy, Sichuan University, Chengdu 610041, China.
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16
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Rima M, Emeraud C, Bonnin RA, Gonzalez C, Dortet L, Iorga BI, Oueslati S, Naas T. Biochemical characterization of OXA-244, an emerging OXA-48 variant with reduced β-lactam hydrolytic activity. J Antimicrob Chemother 2021; 76:2024-2028. [PMID: 33993262 DOI: 10.1093/jac/dkab142] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2021] [Accepted: 04/12/2021] [Indexed: 11/13/2022] Open
Abstract
BACKGROUND OXA-48-producing Enterobacterales have widely disseminated globally with an increasing number of variants identified. Among them, OXA-244 is increasingly reported, despite detection difficulties. OBJECTIVES To determine the steady-state kinetic parameters of OXA-244. METHODS The blaOXA-244 gene was amplified, cloned into plasmids p-TOPO and pET41b+, and transformed into Escherichia coli TOP10 for MIC determination and E. coli BL21 DE3 for purification. Steady-state kinetic parameters and IC50s of clavulanic acid, tazobactam and NaCl were determined using purified OXA-244. Molecular modelling was also performed. RESULTS A reduction in MICs of temocillin and carbapenems was observed in E. coli expressing OXA-244 as compared with OXA-48. The kinetic parameters revealed a reduced carbapenemase activity of OXA-244 as compared with OXA-48, especially for imipenem, which was 10-fold lower. Similarly, catalytic efficiency (kcat/Km) was reduced by 4-fold and 20-fold for ampicillin and temocillin, respectively. Kinetic parameters for cephalosporins were, however, similar. Molecular modelling studies evidenced the key role of R214 in OXA-48, establishing salt bridges with D159 and with the carboxylate group of the R1 substituent of temocillin. These interactions are not possible with G214 in OXA-244, explaining the reduced affinity of temocillin for this enzyme. The R214G mutation in OXA-244 is also likely to induce changes in the active site's water network that would explain the decrease in the hydrolysis rate of carbapenems. CONCLUSIONS Our data confirm that the R214G mutation (present in OXA-244) results in reduced carbapenem- and temocillin-hydrolysing activity, confirming the crucial role of residue 214 in the hydrolysis of these substrates by OXA-48-like β-lactamases.
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Affiliation(s)
- Mariam Rima
- Team ReSIST, INSERM U1184, School of Medicine Université Paris-Saclay, LabEx LERMIT, and Joint Research Unit EERA 'Evolution and Ecology of Resistance to Antibiotics', Institut Pasteur-APHP-University Paris Saclay, Le Kremlin-Bicêtre, France
| | - Cecile Emeraud
- Team ReSIST, INSERM U1184, School of Medicine Université Paris-Saclay, LabEx LERMIT, and Joint Research Unit EERA 'Evolution and Ecology of Resistance to Antibiotics', Institut Pasteur-APHP-University Paris Saclay, Le Kremlin-Bicêtre, France.,Bacteriology-Hygiene Unit, Assistance Publique/Hôpitaux de Paris, Bicêtre Hospital, Le Kremlin-Bicêtre, France.,French National Reference Centre for Antibiotic Resistance: Carbapenemase-Producing Enterobacteriaceae, Le Kremlin-Bicêtre, France
| | - Rémy A Bonnin
- Team ReSIST, INSERM U1184, School of Medicine Université Paris-Saclay, LabEx LERMIT, and Joint Research Unit EERA 'Evolution and Ecology of Resistance to Antibiotics', Institut Pasteur-APHP-University Paris Saclay, Le Kremlin-Bicêtre, France.,French National Reference Centre for Antibiotic Resistance: Carbapenemase-Producing Enterobacteriaceae, Le Kremlin-Bicêtre, France
| | - Camille Gonzalez
- Team ReSIST, INSERM U1184, School of Medicine Université Paris-Saclay, LabEx LERMIT, and Joint Research Unit EERA 'Evolution and Ecology of Resistance to Antibiotics', Institut Pasteur-APHP-University Paris Saclay, Le Kremlin-Bicêtre, France.,Bacteriology-Hygiene Unit, Assistance Publique/Hôpitaux de Paris, Bicêtre Hospital, Le Kremlin-Bicêtre, France
| | - Laurent Dortet
- Team ReSIST, INSERM U1184, School of Medicine Université Paris-Saclay, LabEx LERMIT, and Joint Research Unit EERA 'Evolution and Ecology of Resistance to Antibiotics', Institut Pasteur-APHP-University Paris Saclay, Le Kremlin-Bicêtre, France.,Bacteriology-Hygiene Unit, Assistance Publique/Hôpitaux de Paris, Bicêtre Hospital, Le Kremlin-Bicêtre, France.,French National Reference Centre for Antibiotic Resistance: Carbapenemase-Producing Enterobacteriaceae, Le Kremlin-Bicêtre, France
| | - Bogdan I Iorga
- Université Paris-Saclay, CNRS, Institut de Chimie des Substances Naturelles, Gif-sur-Yvette, France
| | - Saoussen Oueslati
- Team ReSIST, INSERM U1184, School of Medicine Université Paris-Saclay, LabEx LERMIT, and Joint Research Unit EERA 'Evolution and Ecology of Resistance to Antibiotics', Institut Pasteur-APHP-University Paris Saclay, Le Kremlin-Bicêtre, France.,Bacteriology-Hygiene Unit, Assistance Publique/Hôpitaux de Paris, Bicêtre Hospital, Le Kremlin-Bicêtre, France
| | - Thierry Naas
- Team ReSIST, INSERM U1184, School of Medicine Université Paris-Saclay, LabEx LERMIT, and Joint Research Unit EERA 'Evolution and Ecology of Resistance to Antibiotics', Institut Pasteur-APHP-University Paris Saclay, Le Kremlin-Bicêtre, France.,Bacteriology-Hygiene Unit, Assistance Publique/Hôpitaux de Paris, Bicêtre Hospital, Le Kremlin-Bicêtre, France.,French National Reference Centre for Antibiotic Resistance: Carbapenemase-Producing Enterobacteriaceae, Le Kremlin-Bicêtre, France
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17
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Abstract
Class D β-lactamases are composed of 14 families and the majority of the member enzymes are included in the OXA family. The genes for class D β-lactamases are frequently identified in the chromosome as an intrinsic resistance determinant in environmental bacteria and a few of these are found in mobile genetic elements carried by clinically significant pathogens. The most dominant OXA family among class D β-lactamases is superheterogeneous and the family needs to have an updated scheme for grouping OXA subfamilies through phylogenetic analysis. The OXA enzymes, even the members within a subfamily, have a diverse spectrum of resistance. Such varied activity could be derived from their active sites, which are distinct from those of the other serine β-lactamases. Their substrate profile is determined according to the size and position of the P-, Ω- and β5-β6 loops, assembling the active-site channel, which is very hydrophobic. Also, amino acid substitutions occurring in critical structures may alter the range of hydrolysed substrates and one subfamily could include members belonging to several functional groups. This review aims to describe the current class D β-lactamases including the functional groups, occurrence types (intrinsic or acquired) and substrate spectra and, focusing on the major OXA family, a new model for subfamily grouping will be presented.
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Affiliation(s)
- Eun-Jeong Yoon
- Department of Laboratory Medicine and Research Institute of Bacterial Resistance, Yonsei University College of Medicine, Seoul, South Korea
| | - Seok Hoon Jeong
- Department of Laboratory Medicine and Research Institute of Bacterial Resistance, Yonsei University College of Medicine, Seoul, South Korea
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18
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Discovery of Novel Chemical Series of OXA-48 β-Lactamase Inhibitors by High-Throughput Screening. Pharmaceuticals (Basel) 2021; 14:ph14070612. [PMID: 34202402 PMCID: PMC8308845 DOI: 10.3390/ph14070612] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2021] [Revised: 06/21/2021] [Accepted: 06/23/2021] [Indexed: 11/17/2022] Open
Abstract
The major cause of bacterial resistance to β-lactams is the production of hydrolytic β-lactamase enzymes. Nowadays, the combination of β-lactam antibiotics with β-lactamase inhibitors (BLIs) is the main strategy for overcoming such issues. Nevertheless, particularly challenging β-lactamases, such as OXA-48, pose the need for novel and effective treatments. Herein, we describe the screening of a proprietary compound collection against Klebsiella pneumoniae OXA-48, leading to the identification of several chemotypes, like the 4-ideneamino-4H-1,2,4-triazole (SC_2) and pyrazolo[3,4-b]pyridine (SC_7) cores as potential inhibitors. Importantly, the most potent representative of the latter series (ID2, AC50 = 0.99 μM) inhibited OXA-48 via a reversible and competitive mechanism of action, as demonstrated by biochemical and X-ray studies; furthermore, it slightly improved imipenem’s activity in Escherichia coli ATCC BAA-2523 β-lactam resistant strain. Also, ID2 showed good solubility and no sign of toxicity up to the highest tested concentration, resulting in a promising starting point for further optimization programs toward novel and effective non-β-lactam BLIs.
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19
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Stewart NK, Toth M, Stasyuk A, Vakulenko SB, Smith CA. In Crystallo Time-Resolved Interaction of the Clostridioides difficile CDD-1 enzyme with Avibactam Provides New Insights into the Catalytic Mechanism of Class D β-lactamases. ACS Infect Dis 2021; 7:1765-1776. [PMID: 33908775 PMCID: PMC8808381 DOI: 10.1021/acsinfecdis.1c00094] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Class D β-lactamases have risen to notoriety due to their wide spread in bacterial pathogens, propensity to inactivate clinically important β-lactam antibiotics, and ability to withstand inhibition by the majority of classical β-lactamase inhibitors. Understanding the catalytic mechanism of these enzymes is thus vitally important for the development of novel antibiotics and inhibitors active against infections caused by antibiotic-resistant bacteria. Here we report an in crystallo time-resolved study of the interaction of the class D β-lactamase CDD-1 from Clostridioides difficile with the diazobicyclooctane inhibitor, avibactam. We show that the catalytic carboxylated lysine, a residue that is essential for both acylation and deacylation of β-lactams, is sequestered within an internal sealed pocket of the enzyme. Time-resolved snapshots generated in this study allowed us to observe decarboxylation of the lysine and movement of CO2 and water molecules through a transient channel formed between the lysine pocket and the substrate binding site facilitated by rotation of the side chain of a conserved leucine residue. These studies provide novel insights on avibactam binding to CDD-1 and into the catalytic mechanism of class D β-lactamases in general.
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Affiliation(s)
- Nichole K Stewart
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, Indiana 46556, United States
| | - Marta Toth
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, Indiana 46556, United States
| | - Anastasiya Stasyuk
- Stanford Synchrotron Radiation Lightsource, Stanford University, Menlo Park, California 94025, United States
| | - Sergei B Vakulenko
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, Indiana 46556, United States
| | - Clyde A Smith
- Stanford Synchrotron Radiation Lightsource, Stanford University, Menlo Park, California 94025, United States
- Department of Chemistry, Stanford University, Stanford, California 94305, United States
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20
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Antimicrobial Resistance Conferred by OXA-48 β-Lactamases: Towards a Detailed Mechanistic Understanding. Antimicrob Agents Chemother 2021; 65:AAC.00184-21. [PMID: 33753332 DOI: 10.1128/aac.00184-21] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
OXA-48-type β-lactamases are now routinely encountered in bacterial infections caused by carbapenem-resistant Enterobacterales These enzymes are of high and growing clinical significance due to the importance of carbapenems in treatment of health care-associated infections by Gram-negative bacteria, the wide and increasing dissemination of OXA-48 enzymes on plasmids, and the challenges posed by their detection. OXA-48 confers resistance to penicillin (which is efficiently hydrolyzed) and carbapenem antibiotics (which is more slowly broken down). In addition to the parent enzyme, a growing array of variants of OXA-48 is now emerging. The spectrum of activity of these variants varies, with some hydrolyzing expanded-spectrum oxyimino-cephalosporins. The growth in importance and diversity of the OXA-48 group has motivated increasing numbers of studies that aim to elucidate the relationship between structure and specificity and establish the mechanistic basis for β-lactam turnover in this enzyme family. In this review, we collate recently published structural, kinetic, and mechanistic information on the interactions between clinically relevant β-lactam antibiotics and inhibitors and OXA-48 β-lactamases. Collectively, these studies are starting to form a detailed picture of the underlying bases for the differences in β-lactam specificity between OXA-48 variants and the consequent differences in resistance phenotype. We focus specifically on aspects of carbapenemase and cephalosporinase activities of OXA-48 β-lactamases and discuss β-lactamase inhibitor development in this context. Throughout the review, we also outline key open research questions for future investigation.
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21
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Ma CW, Ng KKH, Yam BHC, Ho PL, Kao RYT, Yang D. Rapid Broad Spectrum Detection of Carbapenemases with a Dual Fluorogenic-Colorimetric Probe. J Am Chem Soc 2021; 143:6886-6894. [PMID: 33909441 DOI: 10.1021/jacs.1c00462] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Carbapenems stand as one of the last-resort antibiotics; however, their efficacy is threatened by the rising number and rapid spread of carbapenemases. Effective antimicrobial stewardship thus calls for rapid tests for these enzymes to aid appropriate prescription and infection control. Herein, we report the first effective pan-carbapenemase reporter CARBA-H with a broad scope covering all three Ambler classes. Using a chemical biology approach, we demonstrated that the absence of the 1β-substituent in the carbapenem core is key to pan-carbapenemase recognition, which led to our rational design and probe development. CARBA-H provides a dual colorimetric-fluorogenic response upon carbapenemase-mediated hydrolysis. A clear visual readout can be obtained within 15 min when tested against a panel of carbapenemase-producing Enterobacteriaceae (CPE) clinical isolates that notably includes OXA-48 and OXA-181-producing strains. Furthermore, CARBA-H can be applied to the detection of carbapemenase activity in CPE-spiked urine samples.
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Affiliation(s)
- Chi-Wang Ma
- Morningside Laboratory for Chemical Biology, Department of Chemistry, The University of Hong Kong, Pokfulam Road, Hong Kong, China
| | - Kenneth King-Hei Ng
- Morningside Laboratory for Chemical Biology, Department of Chemistry, The University of Hong Kong, Pokfulam Road, Hong Kong, China
| | - Bill Hin-Cheung Yam
- Department of Microbiology and Carol Yu Centre for Infection, The University of Hong Kong, Pokfulam Road, Hong Kong, China
| | - Pak-Leung Ho
- Department of Microbiology and Carol Yu Centre for Infection, The University of Hong Kong, Pokfulam Road, Hong Kong, China
| | - Richard Yi-Tsun Kao
- Department of Microbiology and Carol Yu Centre for Infection, The University of Hong Kong, Pokfulam Road, Hong Kong, China
| | - Dan Yang
- Morningside Laboratory for Chemical Biology, Department of Chemistry, The University of Hong Kong, Pokfulam Road, Hong Kong, China
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22
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Stojanoski V, Hu L, Sankaran B, Wang F, Tao P, Prasad BVV, Palzkill T. Mechanistic Basis of OXA-48-like β-Lactamases' Hydrolysis of Carbapenems. ACS Infect Dis 2021; 7:445-460. [PMID: 33492952 DOI: 10.1021/acsinfecdis.0c00798] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Carbapenem-hydrolyzing class D β-lactamases (CHDLs) are an important source of resistance to these last resort β-lactam antibiotics. OXA-48 is a member of a group of CHDLs named OXA-48-like enzymes. On the basis of sequence similarity, OXA-163 can be classified as an OXA-48-like enzyme, but it has altered substrate specificity. Compared to OXA-48, it shows impaired activity for carbapenems but displays an enhanced hydrolysis of oxyimino-cephalosporins. Here, we address the mechanistic and structural basis for carbapenem hydrolysis by OXA-48-like enzymes. Pre-steady-state kinetic analysis indicates that the rate-limiting step for OXA-48 and OXA-163 hydrolysis of carbapenems is deacylation and that the greatly reduced carbapenemase activity of OXA-163 compared to that of OXA-48 is due entirely to a slower deacylation reaction. Furthermore, our structural data indicate that the positioning of the β5-β6 loop is necessary for carbapenem hydrolysis by OXA-48. A major difference between the OXA-48 and OXA-163 complexes with carbapenems is that the 214-RIEP-217 deletion in OXA-163 creates a large opening in the active site that is absent in the OXA-48/carbapenem structures. We propose that the larger active site results in less constraint on the conformation of the 6α-hydroxyethyl group in the acyl-enzyme. The acyl-enzyme intermediate assumes multiple conformations, most of which are incompatible with rapid deacylation. Consistent with this hypothesis, molecular dynamics simulations indicate that the most stable complex is formed between OXA-48 and imipenem, which correlates with the OXA-48 hydrolysis of imipenem being the fastest observed. Furthermore, the OXA-163 complexes with imipenem and meropenem are the least stable and show significant conformational fluctuations, which correlates with the slow hydrolysis of these substrates.
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Affiliation(s)
| | | | - Banumathi Sankaran
- Department of Molecular Biophysics and Integrated Bioimaging, Berkeley Center for Structural Biology, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States,
| | - Feng Wang
- Department of Chemistry, Center for Research Computing, Center for Drug Discovery, Design, and Delivery (CD4), Southern Methodist University, Dallas, Texas 75205, United States
| | - Peng Tao
- Department of Chemistry, Center for Research Computing, Center for Drug Discovery, Design, and Delivery (CD4), Southern Methodist University, Dallas, Texas 75205, United States
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Carbapenemases as factors of Resistance to Antibacterial Drugs. ACTA BIOMEDICA SCIENTIFICA 2021. [DOI: 10.29413/abs.2020-5.6.11] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
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Aertker KMJ, Chan HTH, Lohans CT, Schofield CJ. Analysis of β-lactone formation by clinically observed carbapenemases informs on a novel antibiotic resistance mechanism. J Biol Chem 2020; 295:16604-16613. [PMID: 32963107 PMCID: PMC7864059 DOI: 10.1074/jbc.ra120.014607] [Citation(s) in RCA: 8] [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: 05/28/2020] [Revised: 09/07/2020] [Indexed: 01/18/2023] Open
Abstract
An important mechanism of resistance to β-lactam antibiotics is via their β-lactamase-catalyzed hydrolysis. Recent work has shown that, in addition to the established hydrolysis products, the reaction of the class D nucleophilic serine β-lactamases (SBLs) with carbapenems also produces β-lactones. We report studies on the factors determining β-lactone formation by class D SBLs. We show that variations in hydrophobic residues at the active site of class D SBLs (i.e. Trp105, Val120, and Leu158, using OXA-48 numbering) impact on the relative levels of β-lactones and hydrolysis products formed. Some variants, i.e. the OXA-48 V120L and OXA-23 V128L variants, catalyze increased β-lactone formation compared with the WT enzymes. The results of kinetic and product studies reveal that variations of residues other than those directly involved in catalysis, including those arising from clinically observed mutations, can alter the reaction outcome of class D SBL catalysis. NMR studies show that some class D SBL variants catalyze formation of β-lactones from all clinically relevant carbapenems regardless of the presence or absence of a 1β-methyl substituent. Analysis of reported crystal structures for carbapenem-derived acyl-enzyme complexes reveals preferred conformations for hydrolysis and β-lactone formation. The observation of increased β-lactone formation by class D SBL variants, including the clinically observed carbapenemase OXA-48 V120L, supports the proposal that class D SBL-catalyzed rearrangement of β-lactams to β-lactones is important as a resistance mechanism.
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Affiliation(s)
| | - H T Henry Chan
- Chemistry Research Laboratory, University of Oxford, Oxford, United Kingdom
| | - Christopher T Lohans
- Chemistry Research Laboratory, University of Oxford, Oxford, United Kingdom; Department of Biomedical and Molecular Sciences, Queen's University, Kingston, Ontario, Canada.
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De Angelis G, Del Giacomo P, Posteraro B, Sanguinetti M, Tumbarello M. Molecular Mechanisms, Epidemiology, and Clinical Importance of β-Lactam Resistance in Enterobacteriaceae. Int J Mol Sci 2020; 21:ijms21145090. [PMID: 32708513 PMCID: PMC7404273 DOI: 10.3390/ijms21145090] [Citation(s) in RCA: 55] [Impact Index Per Article: 13.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2020] [Revised: 07/13/2020] [Accepted: 07/17/2020] [Indexed: 12/16/2022] Open
Abstract
Despite being members of gut microbiota, Enterobacteriaceae are associated with many severe infections such as bloodstream infections. The β-lactam drugs have been the cornerstone of antibiotic therapy for such infections. However, the overuse of these antibiotics has contributed to select β-lactam-resistant Enterobacteriaceae isolates, so that β-lactam resistance is nowadays a major concern worldwide. The production of enzymes that inactivate β-lactams, mainly extended-spectrum β-lactamases and carbapenemases, can confer multidrug resistance patterns that seriously compromise therapeutic options. Further, β-lactam resistance may result in increases in the drug toxicity, mortality, and healthcare costs associated with Enterobacteriaceae infections. Here, we summarize the updated evidence about the molecular mechanisms and epidemiology of β-lactamase-mediated β-lactam resistance in Enterobacteriaceae, and their potential impact on clinical outcomes of β-lactam-resistant Enterobacteriaceae infections.
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Affiliation(s)
- Giulia De Angelis
- Dipartimento di Scienze Biotecnologiche di Base, Cliniche Intensivologiche e Perioperatorie, Università Cattolica del Sacro Cuore, 00168 Rome, Italy; (G.D.A.); (B.P.); (M.S.)
- Dipartimento di Scienze di Laboratorio e Infettivologiche, Fondazione Policlinico Universitario A. Gemelli IRCCS, 00168 Rome, Italy;
| | - Paola Del Giacomo
- Dipartimento di Scienze di Laboratorio e Infettivologiche, Fondazione Policlinico Universitario A. Gemelli IRCCS, 00168 Rome, Italy;
| | - Brunella Posteraro
- Dipartimento di Scienze Biotecnologiche di Base, Cliniche Intensivologiche e Perioperatorie, Università Cattolica del Sacro Cuore, 00168 Rome, Italy; (G.D.A.); (B.P.); (M.S.)
- Dipartimento di Scienze Gastroenterologiche, Endocrino-Metaboliche e Nefro-Urologiche, Fondazione Policlinico Universitario A. Gemelli IRCCS, 00168 Rome, Italy
| | - Maurizio Sanguinetti
- Dipartimento di Scienze Biotecnologiche di Base, Cliniche Intensivologiche e Perioperatorie, Università Cattolica del Sacro Cuore, 00168 Rome, Italy; (G.D.A.); (B.P.); (M.S.)
- Dipartimento di Scienze di Laboratorio e Infettivologiche, Fondazione Policlinico Universitario A. Gemelli IRCCS, 00168 Rome, Italy;
| | - Mario Tumbarello
- Dipartimento di Scienze di Laboratorio e Infettivologiche, Fondazione Policlinico Universitario A. Gemelli IRCCS, 00168 Rome, Italy;
- Dipartimento di Sicurezza e Bioetica, Università Cattolica del Sacro Cuore, 00168 Rome, Italy
- Correspondence:
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Hirvonen VHA, Mulholland AJ, Spencer J, van der Kamp MW. Small Changes in Hydration Determine Cephalosporinase Activity of OXA-48 β-Lactamases. ACS Catal 2020. [DOI: 10.1021/acscatal.0c00596] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Affiliation(s)
- Viivi H. A. Hirvonen
- School of Biochemistry, University of Bristol, University Walk, Bristol, BS8 1TD United Kingdom
- Centre for Computational Chemistry, School of Chemistry, University of Bristol, Cantock’s Close, Bristol, BS8 1TS United Kingdom
| | - Adrian J. Mulholland
- Centre for Computational Chemistry, School of Chemistry, University of Bristol, Cantock’s Close, Bristol, BS8 1TS United Kingdom
| | - James Spencer
- School of Cellular and Molecular Medicine, University of Bristol, University Walk, Bristol, BS8 1TD United Kingdom
| | - Marc W. van der Kamp
- School of Biochemistry, University of Bristol, University Walk, Bristol, BS8 1TD United Kingdom
- Centre for Computational Chemistry, School of Chemistry, University of Bristol, Cantock’s Close, Bristol, BS8 1TS United Kingdom
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Akhtar A, Pemberton OA, Chen Y. Structural Basis for Substrate Specificity and Carbapenemase Activity of OXA-48 Class D β-Lactamase. ACS Infect Dis 2020; 6:261-271. [PMID: 31872762 DOI: 10.1021/acsinfecdis.9b00304] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Carbapenem-hydrolyzing class D β-lactamases (CHDLs) are a diverse family of enzymes that are rapidly becoming the predominant cause of bacterial resistance against β-lactam antibiotics in many regions of the world. OXA-48, an atypical member of CHDLs, is one of the most frequently observed in the clinic and exhibits a unique substrate profile. We applied X-ray crystallography to OXA-48 complexes with multiple β-lactam antibiotics to elucidate this enzyme's carbapenemase activity and its preference of imipenem over meropenem and other substrates such as cefotaxime. In particular, we obtained acyl-enzyme complexes of OXA-48 with imipenem, meropenem, faropenem, cefotaxime, and cefoxitin, and a product complex with imipenem. Importantly, the product complex captures a key reaction milestone with the newly generated carboxylate group still in the oxyanion hole, and represents the first such complex with a wild-type serine β-lactamase. A potential hydrogen bond is observed between the two carboxylate groups from the product and the carbamylated Lys73, representing the stage immediately after the breakage of the acyl-enzyme bond where the product carboxylate would be neutral. The placement of the product carboxylate also illustrates the approximate transient location of the deacylation water that has long eluded structural characterization in class D β-lactamases. Additionally, comparing the product complex with the acyl-enzyme intermediates provides new insights into the various mechanisms by which specific side chain groups hinder the access of the deacylation water to the acyl-enzyme linkage, especially in meropenem. Taken together, these data offer valuable information on the substrate specificity of OXA-48 and the catalytic mechanism of CHDLs.
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Affiliation(s)
- Afroza Akhtar
- Department of Molecular Medicine, University of South Florida Morsani College of Medicine, 12901 Bruce B. Downs Boulevard, MDC 3522, Tampa, Florida 33612, United States
| | - Orville A. Pemberton
- Department of Molecular Medicine, University of South Florida Morsani College of Medicine, 12901 Bruce B. Downs Boulevard, MDC 3522, Tampa, Florida 33612, United States
| | - Yu Chen
- Department of Molecular Medicine, University of South Florida Morsani College of Medicine, 12901 Bruce B. Downs Boulevard, MDC 3522, Tampa, Florida 33612, United States
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Structural Analysis of The OXA-48 Carbapenemase Bound to A "Poor" Carbapenem Substrate, Doripenem. Antibiotics (Basel) 2019; 8:antibiotics8030145. [PMID: 31514291 PMCID: PMC6783824 DOI: 10.3390/antibiotics8030145] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2019] [Revised: 08/30/2019] [Accepted: 09/04/2019] [Indexed: 12/11/2022] Open
Abstract
Carbapenem-resistant Enterobacteriaceae are a significant threat to public health, and a major resistance determinant that promotes this phenotype is the production of the OXA-48 carbapenemase. The activity of OXA-48 towards carbapenems is a puzzling phenotype as its hydrolytic activity against doripenem is non-detectable. To probe the mechanistic basis for this observation, we determined the 1.5 Å resolution crystal structure of the deacylation deficient K73A variant of OXA-48 in complex with doripenem. Doripenem is observed in the Δ1R and Δ1S tautomeric states covalently attached to the catalytic S70 residue. Likely due to positioning of residue Y211, the carboxylate moiety of doripenem is making fewer hydrogen bonding/salt-bridge interactions with R250 compared to previously determined carbapenem OXA structures. Moreover, the hydroxyethyl side chain of doripenem is making van der Waals interactions with a key V120 residue, which likely affects the deacylation rate of doripenem. We hypothesize that positions V120 and Y211 play important roles in the carbapenemase profile of OXA-48. Herein, we provide insights for the further development of the carbapenem class of antibiotics that could render them less effective to hydrolysis by or even inhibit OXA carbapenemases.
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