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Feng W, Lv J, Wang H, Yao P, Xiong L, Xia P, Yuan Q, Sun F. The first report of the bla IMP-10 gene and complete sequence of the IMP-10-encoding plasmid p12NE515 from Pseudomonas aeruginosa in China. Acta Trop 2022; 228:106326. [PMID: 35077675 DOI: 10.1016/j.actatropica.2022.106326] [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: 12/21/2021] [Revised: 01/20/2022] [Accepted: 01/20/2022] [Indexed: 12/31/2022]
Abstract
OBJECTIVE To investigate a detailed genomic characterization of the blaIMP-10-carrying plasmid p12NE515 from a Pseudomonas aeruginosa isolate in China. METHODS Plasmid p12NE515 was subjected to whole-genome sequencing and the complete sequence was compared with related plasmid sequences. Transferability of plasmid, carbapenemase activity and bacterial susceptibility profiles were determined to assess p12NE515-mediated resistance phenotypes. RESULTS P. aeruginosa 12NE515 was identified as a less common sequence type of ST1976. p12NE515 harboring blaIMP-10 possessed a backbone identical to plasmid p60512-IMP (carrying blaIMP-1), but the accessory resistance regions differed. Only one accessory module, Tn7339, was carried in p12NE515, and this transposon was an insertion sequence-mediated transposition unit generated by the insertion of a novel class 1 integron, In1814, at the downstream end of ISPa17. Here, blaIMP-10 together with aacA7 was located in In1814, being at evolution stage III of Tn402-associated integron due to truncation of the tni module. CONCLUSION This study is the first to determine the complete sequence of a blaIMP-10-carrying plasmid, and this is also the first report of a blaIMP-10-producing strain in China. The prevalence of the blaIMP-10 gene and the genetic characterization of the blaIMP-10-carrying plasmid should be analyzed to provide deeper insight into the transmission mechanism of antimicrobial resistance genes.
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Affiliation(s)
- Wei Feng
- Department of Pharmacy, Southwest Hospital, Third Military Medical University (Army Medical University), Chongqing 400038, China
| | - Jun Lv
- Department of Pharmacy, Southwest Hospital, Third Military Medical University (Army Medical University), Chongqing 400038, China
| | - Hongping Wang
- Department of Pharmacy, Southwest Hospital, Third Military Medical University (Army Medical University), Chongqing 400038, China
| | - Pu Yao
- Department of Pharmacy, Southwest Hospital, Third Military Medical University (Army Medical University), Chongqing 400038, China
| | - Lirong Xiong
- Department of Pharmacy, Southwest Hospital, Third Military Medical University (Army Medical University), Chongqing 400038, China
| | - Peiyuan Xia
- Department of Pharmacy, Southwest Hospital, Third Military Medical University (Army Medical University), Chongqing 400038, China
| | - Qian Yuan
- Department of Pharmacy, Southwest Hospital, Third Military Medical University (Army Medical University), Chongqing 400038, China.
| | - Fengjun Sun
- Department of Pharmacy, Southwest Hospital, Third Military Medical University (Army Medical University), Chongqing 400038, China.
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Abstract
PURPOSE OF REVIEW In recent years, traditional β-lactams have dramatically reduced their effectiveness against gram-negative bacteria mainly because of their ability to express multiple β-lactamase or carabapenemases that are not hydrolyzed by the old β-lactam inhibitors (BLIs) such as clavulanic acid, tazobactam, and sulbactam. New BLIs molecules have been developed to face the need of compounds that are active against multidrug or pandrug resistant gram-negative pathogens. The aim of this review is to summarize the new generation of BLIs and β-lactams combinations. RECENT FINDINGS A number of new molecules with activity against Ambler class A (e.g., extended-spectrum β-lactamases, serine carbapenemases), class C (e.g., AmpC), or class D (e.g., oxacillinase-48) have been recently approved in combination with old β-lactams for the treatment of multidrug-resistant bacteria, and other agents are under investigation. These new compounds include diazabicyclooctanones non-β-lactam inhibitors (e.g., avibactam, relebactam, nacubactam) and boronic acid inhibitors (e.g., vaborbactam). SUMMARY Newly approved and investigational new BLIs are expected to offer many advantages for the management of patients with multidrug-resistant gram-negative pathogens. Promising characteristics of new compounds include high activity against multi drug resistance gram-negative bacteria and a favorable safety profile.
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Kurosu M, Siricilla S, Mitachi K. Advances in MRSA drug discovery: where are we and where do we need to be? Expert Opin Drug Discov 2013; 8:1095-116. [PMID: 23829425 DOI: 10.1517/17460441.2013.807246] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
INTRODUCTION Methicillin-resistant Staphylococcus aureus (MRSA) have been on the increase during the past decade, due to the steady growth of the elderly and immunocompromised patients, and the emergence of multidrug-resistant (MDR) bacterial strains. Although there are a limited number of anti-MRSA drugs available, a number of different combination antimicrobial drug regimens have been used to treat serious MRSA infections. Thus, the addition of several new antistaphylococcal drugs into clinical practice should broaden clinician's therapeutic options. As MRSA is one of the most common and problematic bacteria associated with increasing antimicrobial resistance, continuous efforts for the discovery of lead compounds as well as development of alternative therapies and faster diagnostics are required. AREAS COVERED This article summarizes the FDA-approved drugs to treat MRSA infections, the drugs in clinical trials, and the drug leads for MRSA and related Gram-positive bacterial infections. In addition, the article discusses the mode of action of antistaphylococcal molecules and the resistant mechanisms of some molecules. EXPERT OPINION The number of pipeline drugs presently undergoing clinical trials is not particularly encouraging. There are limited and rather expensive therapeutic options for MRSA infections in the critically ill. Further research efforts are required for effective phage therapy on MRSA infections in clinical use, which seem to be attractive therapeutic options for the future.
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Affiliation(s)
- Michio Kurosu
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Tennessee, 881 Madison Avenue, Memphis, TN 38163, USA.
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4
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Paradkar A. Clavulanic acid production by Streptomyces clavuligerus: biogenesis, regulation and strain improvement. J Antibiot (Tokyo) 2013; 66:411-20. [DOI: 10.1038/ja.2013.26] [Citation(s) in RCA: 50] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2013] [Revised: 02/25/2013] [Accepted: 03/11/2013] [Indexed: 11/09/2022]
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Docquier JD, Benvenuti M, Calderone V, Rossolini GM, Mangani S. Structure of the extended-spectrum β-lactamase TEM-72 inhibited by citrate. Acta Crystallogr Sect F Struct Biol Cryst Commun 2011; 67:303-6. [PMID: 21393831 PMCID: PMC3053151 DOI: 10.1107/s1744309110054680] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2010] [Accepted: 12/29/2010] [Indexed: 11/10/2022]
Abstract
TEM-72, a class A β-lactamase identified in isolates of Enterobacteriaceae, is a quadruple mutant of TEM-1 (Q39K, M182T, G238S and E240K) and shows extended-spectrum β-lactamase (ESBL) properties arising from the G238S and E240K substitutions. Although many structures of TEM variants have been published, they do not include an enzyme with the simultaneous presence of both of the ESBL-conferring G238S and E240K substitutions. Furthermore, the structure shows the presence of a citrate anion bound to the TEM-72 active site, where it interacts with all of the conserved residues of class A β-lactamases. The present structure supports the use of polycarboxylates as a scaffold for the design of broad-spectrum inhibitors of serine β-lactamases.
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Affiliation(s)
- Jean-Denis Docquier
- Dipartimento di Biologia Molecolare, Laboratorio di Fisiologia e Biotecnologia dei Microrganismi, Università di Siena, I-53100 Siena, Italy
| | | | - Vito Calderone
- Magnetic Resonance Center CERM, Università di Firenze, I-50019 Sesto Fiorentino, Italy
| | - Gian-Maria Rossolini
- Dipartimento di Biologia Molecolare, Laboratorio di Fisiologia e Biotecnologia dei Microrganismi, Università di Siena, I-53100 Siena, Italy
- U. O. C. Microbiologia e Virologia, Università di Siena, I-53100 Siena, Italy
| | - Stefano Mangani
- Dipartimento di Chimica, Università di Siena, I-53100 Siena, Italy
- Magnetic Resonance Center CERM, Università di Firenze, I-50019 Sesto Fiorentino, Italy
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6
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Touchet S, Carreaux F, Carboni B, Bouillon A, Boucher JL. Aminoboronic acids and esters: from synthetic challenges to the discovery of unique classes of enzyme inhibitors. Chem Soc Rev 2011; 40:3895-914. [DOI: 10.1039/c0cs00154f] [Citation(s) in RCA: 112] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
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Natural and synthetic small boron-containing molecules as potential inhibitors of bacterial and fungal quorum sensing. Chem Rev 2010; 111:209-37. [PMID: 21171664 DOI: 10.1021/cr100093b] [Citation(s) in RCA: 142] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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8
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Johnson JW, Gretes M, Goodfellow VJ, Marrone L, Heynen ML, Strynadka NCJ, Dmitrienko GI. Cyclobutanone Analogues of β-Lactams Revisited: Insights into Conformational Requirements for Inhibition of Serine- and Metallo-β-Lactamases. J Am Chem Soc 2010; 132:2558-60. [DOI: 10.1021/ja9086374] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Jarrod W. Johnson
- Department of Chemistry, University of Waterloo, 200 University Avenue West, Waterloo, Ontario, Canada N2L 3G1, and Department of Biochemistry and Molecular Biology and the Center for Blood Research, University of British Columbia, 2350 Health Sciences Mall, Vancouver, British Columbia, Canada V6T 1Z3
| | - Michael Gretes
- Department of Chemistry, University of Waterloo, 200 University Avenue West, Waterloo, Ontario, Canada N2L 3G1, and Department of Biochemistry and Molecular Biology and the Center for Blood Research, University of British Columbia, 2350 Health Sciences Mall, Vancouver, British Columbia, Canada V6T 1Z3
| | - Valerie J. Goodfellow
- Department of Chemistry, University of Waterloo, 200 University Avenue West, Waterloo, Ontario, Canada N2L 3G1, and Department of Biochemistry and Molecular Biology and the Center for Blood Research, University of British Columbia, 2350 Health Sciences Mall, Vancouver, British Columbia, Canada V6T 1Z3
| | - Laura Marrone
- Department of Chemistry, University of Waterloo, 200 University Avenue West, Waterloo, Ontario, Canada N2L 3G1, and Department of Biochemistry and Molecular Biology and the Center for Blood Research, University of British Columbia, 2350 Health Sciences Mall, Vancouver, British Columbia, Canada V6T 1Z3
| | - Miriam L. Heynen
- Department of Chemistry, University of Waterloo, 200 University Avenue West, Waterloo, Ontario, Canada N2L 3G1, and Department of Biochemistry and Molecular Biology and the Center for Blood Research, University of British Columbia, 2350 Health Sciences Mall, Vancouver, British Columbia, Canada V6T 1Z3
| | - Natalie C. J. Strynadka
- Department of Chemistry, University of Waterloo, 200 University Avenue West, Waterloo, Ontario, Canada N2L 3G1, and Department of Biochemistry and Molecular Biology and the Center for Blood Research, University of British Columbia, 2350 Health Sciences Mall, Vancouver, British Columbia, Canada V6T 1Z3
| | - Gary I. Dmitrienko
- Department of Chemistry, University of Waterloo, 200 University Avenue West, Waterloo, Ontario, Canada N2L 3G1, and Department of Biochemistry and Molecular Biology and the Center for Blood Research, University of British Columbia, 2350 Health Sciences Mall, Vancouver, British Columbia, Canada V6T 1Z3
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9
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Igličar P, Legen I, Vilfan G, Selič L, Preželj A. Permeability of a novel β-lactamase inhibitor LK-157 and its ester prodrugs across rat jejunum in vitro. J Pharm Pharmacol 2010. [DOI: 10.1211/jpp.61.09.0011] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022]
Abstract
Abstract
Objectives
LK-157 is a novel 10-ethylidene tricyclic carbapenem that resembles the structure of the broad-spectrum antibiotic sanfetrinem and acts as a potent inactivator of β-lactamases of classes A, C and D. LK-157 is a highly soluble but poorly permeable drug. Since most of the β-lactams are poorly absorbed, ester prodrugs LK-159, LK-157E1 and LK-157E2 were designed to enhance membrane permeability. This study investigated the permeability of LK-157 and the three ester prodrugs across rat intestine in vitro. The morpholinoethyl ester of sanfetrinem was also investigated.
Method
Permeability across rat jejunum was determined using EasyMount side-by-side diffusion chambers.
Key findings
The solubility and permeability of morpholinoethyl ester LK-157E2 were superior to those of LK-159 and LK-157E1. The morpholinoethyl ester of sanfetrinem LK-176E1 had the highest observed permeability coefficient and consequently the highest predicted absorption in humans.
Conclusions
These results suggest that the morpholinoethyl esters of LK-157 and sanfetrinem could be further investigated to assess bioavailability in vivo.
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Affiliation(s)
| | - Igor Legen
- Lek Pharmaceuticals d.d., Ljubljana, Slovenia
| | | | - Lovro Selič
- Lek Pharmaceuticals d.d., Ljubljana, Slovenia
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10
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Betrosian AP, Douzinas EE. Ampicillin-sulbactam: an update on the use of parenteral and oral forms in bacterial infections. Expert Opin Drug Metab Toxicol 2009; 5:1099-112. [PMID: 19621991 DOI: 10.1517/17425250903145251] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
Ampicillin-sulbactam has a wide range of antibacterial activity that includes Gram-positive and Gram-negative aerobic and anaerobic bacteria. However, the drug is not active against Pseudomonas aeruginosa and pathogens producing extended-spectrum beta-lactamases. The combination could be considered particularly active against Acinetobacter baumannii infections due to the intrinsic activity of sulbactam. The drug is indicated as empirical therapy for a broad range of community acquired infections supervened in adults or children and is effective in either parenteral (ampicillin-sulbactam) or oral (as a mutual prodrug sultamicillin) form. In clinical trials, sultamicillin has proved clinically and bacteriologically effective in adults and children against a variety of frequently encountered infections, including mild upper and lower respiratory tract infections, urinary tract infections, diabetic foot and skin and soft tissue infections. Furthermore, adverse effects rarely occur with the diarrhoea to represent the most commonly reported. The parenteral ampicillin-sulbactam is indicated for community infections of mild-to-moderate severity acquired infections such as intra-abdominal or gynecological. Moreover, it seems to represent the alternative of choice for the treatment of A. baumannii infections for carbapenem-resistant strains in the nosocomial setting. Thus, ampicillin-sulbactam remains a valuable agent in the physician's armamentarium in the management of adult and pediatric infections.
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Affiliation(s)
- Alex P Betrosian
- Athens University, Evgenidion Hospital, 3rd Department of Critical Care, Greece.
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11
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Brown NG, Shanker S, Prasad BVV, Palzkill T. Structural and biochemical evidence that a TEM-1 beta-lactamase N170G active site mutant acts via substrate-assisted catalysis. J Biol Chem 2009; 284:33703-12. [PMID: 19812041 DOI: 10.1074/jbc.m109.053819] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
TEM-1 beta-lactamase is the most common plasmid-encoded beta-lactamase in Gram-negative bacteria and is a model class A enzyme. The active site of class A beta-lactamases share several conserved residues including Ser(70), Glu(166), and Asn(170) that coordinate a hydrolytic water involved in deacylation. Unlike Ser(70) and Glu(166), the functional significance of residue Asn(170) is not well understood even though it forms hydrogen bonds with both Glu(166) and the hydrolytic water. The goal of this study was to examine the importance of Asn(170) for catalysis and substrate specificity of beta-lactam antibiotic hydrolysis. The codon for position 170 was randomized to create a library containing all 20 possible amino acids. The random library was introduced into Escherichia coli, and functional clones were selected on agar plates containing ampicillin. DNA sequencing of the functional clones revealed that only asparagine (wild type) and glycine at this position are consistent with wild-type function. The determination of kinetic parameters for several substrates revealed that the N170G mutant is very efficient at hydrolyzing substrates that contain a primary amine in the antibiotic R-group that would be close to the Asn(170) side chain in the acyl-intermediate. In addition, the x-ray structure of the N170G enzyme indicated that the position of an active site water important for deacylation is altered compared with the wild-type enzyme. Taken together, the results suggest the N170G TEM-1 enzyme hydrolyzes ampicillin efficiently because of substrate-assisted catalysis where the primary amine of the ampicillin R-group positions the hydrolytic water and allows for efficient deacylation.
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Affiliation(s)
- Nicholas G Brown
- Department of Biochemistry and Molecular Biology, Baylor College of Medicine, Houston, Texas 77030, USA
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12
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Simona F, Magistrato A, Dal Peraro M, Cavalli A, Vila AJ, Carloni P. Common mechanistic features among metallo-beta-lactamases: a computational study of Aeromonas hydrophila CphA enzyme. J Biol Chem 2009; 284:28164-28171. [PMID: 19671702 DOI: 10.1074/jbc.m109.049502] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Metallo-beta-lactamases (MbetaLs) constitute an increasingly serious clinical threat by giving rise to beta-lactam antibiotic resistance. They accommodate in their catalytic pocket one or two zinc ions, which are responsible for the hydrolysis of beta-lactams. Recent x-ray studies on a member of the mono-zinc B2 MbetaLs, CphA from Aeromonas hydrophila, have paved the way to mechanistic studies of this important subclass, which is selective for carbapenems. Here we have used hybrid quantum mechanical/molecular mechanical methods to investigate the enzymatic hydrolysis by CphA of the antibiotic biapenem. Our calculations describe the entire reaction and point to a new mechanistic description, which is in agreement with the available experimental evidence. Within our proposal, the zinc ion properly orients the antibiotic while directly activating a second catalytic water molecule for the completion of the hydrolytic cycle. This mechanism provides an explanation for a variety of mutagenesis experiments and points to common functional facets across B2 and B1 MbetaLs.
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Affiliation(s)
- Fabio Simona
- Laboratory of Computational Chemistry and Biochemistry, Department für Chemie und Biochemie, Universität Bern, Freiestrasse 3, CH-3012 Bern, Switzerland
| | - Alessandra Magistrato
- CNR-INFM-Democritos National Simulation Center, via Beirut 4, 34014 Grignano, Trieste, Italy; SISSA, Via Beirut 2-4, 34014 Grignano, Trieste, Italy
| | - Matteo Dal Peraro
- Laboratory for Biomolecular Modeling, Institute of Bioengineering, School of Life Sciences, Ecole Polytechnique Fédérale de Lausanne, EPFL, CH-1015 Lausanne, Switzerland
| | - Andrea Cavalli
- Department of Pharmaceutical Sciences, University of Bologna, Via Belmeloro 6, I-40126 Bologna, Italy; Department of Drug Discovery and Development, Italian Institute of Technology, Via Morego 30, I-16163 Genova, Italy
| | - Alejandro J Vila
- Instituto de BiologiaMolecular y Celular de Rosario, Facultad de Bioquímicas y Farmaceuticas, Universidad Nacional de Rosario, Suipacha 531, S2002LRK Rosario, Argentina
| | - Paolo Carloni
- SISSA, Via Beirut 2-4, 34014 Grignano, Trieste, Italy.
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Metallo-β-lactamases in Gram-negative bacteria: introducing the era of pan-resistance? Int J Antimicrob Agents 2009; 33:405.e1-7. [DOI: 10.1016/j.ijantimicag.2008.09.003] [Citation(s) in RCA: 98] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2008] [Accepted: 09/03/2008] [Indexed: 11/22/2022]
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Ganta SR, Perumal S, Pagadala SRR, Samuelsen Ø, Spencer J, Pratt RF, Buynak JD. Approaches to the simultaneous inactivation of metallo- and serine-beta-lactamases. Bioorg Med Chem Lett 2009; 19:1618-22. [PMID: 19243936 PMCID: PMC2896329 DOI: 10.1016/j.bmcl.2009.02.018] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2008] [Revised: 01/31/2009] [Accepted: 02/03/2009] [Indexed: 11/16/2022]
Abstract
A series of cephalosporin-derived reverse hydroxamates and oximes were prepared and evaluated as inhibitors of representative metallo- and serine-beta-lactamases. The reverse hydroxamates showed submicromolar inhibition of the GIM-1 metallo-beta-lactamase. With respect to interactions with the classes A, C, and D serine beta-lactamases, as judged by their correspondingly low K(m) values, the reverse hydroxamates were recognized in a manner similar to the non-hydroxylated N-H amide side chains of the natural substrates of these enzymes. This indicates that, with respect to recognition in the active site of the serine beta-lactamases, the OC-NR-OH functionality can function as a structural isostere of the OC-NR-H group, with the N-O-H group presumably replacing the amide N-H group as a hydrogen bond donor to the appropriate backbone carbonyl oxygen of the protein. The reverse hydroxamates, however, displayed k(cat) values up to three orders of magnitude lower than the natural substrates, thus indicating substantial slowing of the hydrolytic action of these serine beta-lactamases. Although the degree of inactivation is not yet enough to be clinically useful, these initial results are promising. The substitution of the amide N-H bond by N-OH may represent a useful strategy for the inhibition of other serine hydrolases.
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Affiliation(s)
| | - Senthil Perumal
- Department of Chemistry, Wesleyan University, Middletown, CT 06459
| | | | - Ørjan Samuelsen
- Department of Cellular and Molecular Medicine, University of Bristol School of Medical Sciences, University Walk, Bristol BS8 1TD, United Kingdom
- Reference Centre for Detection of Antimicrobial Resistance, Department of Microbiology and Infection Control, University Hospital of North Norway, N-9038 Tromso, Norway
| | - James Spencer
- Department of Cellular and Molecular Medicine, University of Bristol School of Medical Sciences, University Walk, Bristol BS8 1TD, United Kingdom
| | - R. F. Pratt
- Department of Chemistry, Wesleyan University, Middletown, CT 06459
| | - John D. Buynak
- Department of Chemistry, Southern Methodist University, Dallas TX 75275-0314
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Paukner S, Hesse L, Prezelj A, Solmajer T, Urleb U. In vitro activity of LK-157, a novel tricyclic carbapenem as broad-spectrum {beta}-lactamase inhibitor. Antimicrob Agents Chemother 2009; 53:505-11. [PMID: 19075067 PMCID: PMC2630636 DOI: 10.1128/aac.00085-08] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2008] [Revised: 03/30/2008] [Accepted: 11/27/2008] [Indexed: 11/20/2022] Open
Abstract
LK-157 is a novel tricyclic carbapenem with potent activity against class A and class C beta-lactamases. When tested against the purified TEM-1 and SHV-1 enzymes, LK-157 exhibited 50% inhibitory concentrations (IC(50)s) in the ranges of the clavulanic acid and tazobactam IC(50)s (55 nM and 151 nM, respectively). Moreover, LK-157 significantly inhibited AmpC beta-lactamase (IC(50), 62 nM), as LK-157 was >2,000-fold more potent than clavulanic acid and approximately 28-fold more active than tazobactam. The in vitro activities of LK-157 in combination with amoxicillin, piperacillin, ceftazidime, cefotaxime, ceftriaxone, cefepime, cefpirome, and aztreonam against an array of Ambler class A (TEM-, SHV-, CTX-M-, KPC-, PER-, BRO-, and PC-type)- and class C-producing bacterial strains derived from clinical settings were evaluated in synergism experiments and compared with those of clavulanic acid, tazobactam, and sulbactam. In vitro MICs against ESBL-producing strains (except CTX-M-containing strains) were reduced 2- to >256-fold, and those against AmpC-producing strains were reduced even up to >32-fold. The lowest MICs (< or =0.025 to 1.6 microg/ml) were observed for the combination of cefepime and cefpirome with a constant LK-157 concentration of 4 microg/ml, thus raising an interest for further development. LK-157 proved to be a potent beta-lactamase inhibitor, combining activity against class A and class C beta-lactamases, which is an absolute necessity for use in the clinical setting due to the worldwide increasing prevalence of bacterial strains resistant to beta-lactam antibiotics.
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Calvo J, Martínez-Martínez L. Mecanismos de acción de los antimicrobianos. Enferm Infecc Microbiol Clin 2009; 27:44-52. [DOI: 10.1016/j.eimc.2008.11.001] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2008] [Accepted: 11/06/2008] [Indexed: 11/28/2022]
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17
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Johnson JW, Evanoff DP, Savard ME, Lange G, Ramadhar TR, Assoud A, Taylor NJ, Dmitrienko GI. Cyclobutanone Mimics of Penicillins: Effects of Substitution on Conformation and Hemiketal Stability. J Org Chem 2008; 73:6970-82. [PMID: 18710291 DOI: 10.1021/jo801274m] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Jarrod W. Johnson
- Department of Chemistry, University of Waterloo, 200 University Avenue West, Waterloo, Ontario, Canada N2L 3G1
| | - Darryl P. Evanoff
- Department of Chemistry, University of Waterloo, 200 University Avenue West, Waterloo, Ontario, Canada N2L 3G1
| | - Marc E. Savard
- Department of Chemistry, University of Waterloo, 200 University Avenue West, Waterloo, Ontario, Canada N2L 3G1
| | - Gerald Lange
- Department of Chemistry, University of Waterloo, 200 University Avenue West, Waterloo, Ontario, Canada N2L 3G1
| | - Timothy R. Ramadhar
- Department of Chemistry, University of Waterloo, 200 University Avenue West, Waterloo, Ontario, Canada N2L 3G1
| | - Abdeljalil Assoud
- Department of Chemistry, University of Waterloo, 200 University Avenue West, Waterloo, Ontario, Canada N2L 3G1
| | - Nicholas J. Taylor
- Department of Chemistry, University of Waterloo, 200 University Avenue West, Waterloo, Ontario, Canada N2L 3G1
| | - Gary I. Dmitrienko
- Department of Chemistry, University of Waterloo, 200 University Avenue West, Waterloo, Ontario, Canada N2L 3G1
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Adediran SA, Pratt RF. Inhibition of serine beta-lactamases by vanadate-catechol complexes. Biochemistry 2008; 47:9467-74. [PMID: 18702503 DOI: 10.1021/bi801153j] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
All three classes of serine beta-lactamases are inhibited at micromolar levels by 1:1 complexes of catechols with vanadate. Vanadate reacts with catechols at submillimolar concentrations in aqueous buffer at neutral pH in several steps, initially forming 1:1, 1:2, and, possibly, 1:3 complexes. Formation of these complexes is followed by the slower reduction of vanadate (V (V)) to vanadyl (V (IV)) and oxidation of the catechol. Vanadyl-catechol complexes, however, do not inhibit the beta-lactamases. Rate and equilibrium constants of formation of the 1:1 and 1:2 complexes of vanadate with catechol itself and with 2,3-dihydroxynaphthalene were measured by stopped-flow spectrophotometry. Typical examples of all three classes of serine beta-lactamases (the class A TEM-2, class C P99, and class D OXA-1 enzymes) were competitively inhibited by the 1:1 vanadate-catechol complexes. The inhibition was modestly enhanced by hydrophobic substituents on the catechol. The 1:1 vanadate complexes are considerably better inhibitors of the P99 beta-lactamase than 1:1 complexes of catechol with boric acid and are likely to contain penta- or hexacoordinated vanadium rather than tetracooordinated. Molecular modeling showed that a pentacoordinated 1:1 vanadate-catechol complex readily fits into the class C beta-lactamase active site with coordination to the nucleophilic serine hydroxyl oxygen. Such complexes may resemble the pentacoordinated transition states of phosphyl transfer, a reaction also catalyzed by beta-lactamases.
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Affiliation(s)
- S A Adediran
- Department of Chemistry, Wesleyan University, Middletown, Connecticut 06459, USA
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Hu Z, Gunasekera TS, Spadafora L, Bennett B, Crowder MW. Metal content of metallo-beta-lactamase L1 is determined by the bioavailability of metal ions. Biochemistry 2008; 47:7947-53. [PMID: 18597493 DOI: 10.1021/bi8004768] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
In an effort to probe whether the metal content of metallo-beta-lactamase L1 is affected by metal ion bioavailability, L1 was overexpressed as mature protein (M-L1) and full-length (FL-L1) analogues, and the analogues were characterized with metal analyses, kinetics, and EPR spectroscopy. FL-L1, containing the putative leader sequence, was localized in the periplasm of Escherichia coli and shown to bind Zn(II) preferentially. The metal content of FL-L1 could be altered if the enzyme was overexpressed in minimal medium containing Fe and Mn, and surprisingly, an Fe-binding analogue was obtained. On the other hand, M-L1, lacking the putative leader sequence, was localized in the cytoplasm of E. coli and shown to bind various amounts of Fe and Zn(II), and like FL-L1, the metal content of the resulting enzyme could be affected by the amount of metal ions in the growth medium. L1 was refolded in the presence of Fe, and a dinuclear Fe-containing analogue of L1 was obtained, although this analogue is catalytically inactive. EPR spectra demonstrate the presence of an antiferromagnetically coupled Fe(III)Fe(II) center in Fe-containing L1 and suggest the presence of a Fe(III)Zn(II) center in M-L1. Metal analyses on the cytoplasmic and periplasmic fractions of E. coli showed that the concentration of metal ions in the periplasm is not tightly controlled and increases as the concentration of metal ions in the growth medium increases. In contrast, the concentration of Zn(II) in the cytoplasm is tightly controlled while that of Fe is less so.
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Affiliation(s)
- Zhenxin Hu
- Department of Chemistry and Biochemistry, 160 Hughes Hall, Miami University, Oxford, Ohio 45056, USA
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Abstract
The continued increase in antibiotic resistance among bacterial pathogens, coupled with a decrease in infectious disease research among pharmaceutical companies, has escalated the need for novel and effective antibacterial chemotherapies. While current agents have emerged almost exclusively from whole-cell screening of natural products and small molecules that cause microbial death, recent advances in target identification and assay development have resulted in a flood of target-driven drug discovery methods. Whether genome-based methodologies will yield new classes of agents that conventional methods have been unable to is yet to be seen. At the end of the day, perhaps a synergy between old and new approaches will harvest the next generation of antibacterial treatments.
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Safdar A, Rolston KV. Stenotrophomonas maltophilia: changing spectrum of a serious bacterial pathogen in patients with cancer. Clin Infect Dis 2008; 45:1602-9. [PMID: 18190323 DOI: 10.1086/522998] [Citation(s) in RCA: 142] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
Abstract
Stenotrophomonas maltophilia colonization/infection in patients with cancer has significantly increased over the past 2 decades. Patients with prolonged neutropenia, exposure to broad-spectrum antibiotics, and those requiring mechanical ventilation have higher risk of infection. These micro-organisms are intrinsically resistant to carbapenems, and exposure to these agents has been linked to selection of S. maltophilia. Recently, these infections are being documented in patients without traditional risk factors. The spectrum of infection includes bacteremia, catheter-related infection, pneumonia, complicated biliary and urinary tract infection, and skin and skin-structure infection. Trimethoprim-sulfamethoxazole is the therapeutic agent of choice, but resistance is increasingly being reported. Susceptibility to alternative agents is unpredictable. Combination therapy and alternative routes of drug administration, such as aerosolized aminoglycoside, might be necessary. New insights into the mechanisms of drug resistance might lead to identification of new target sites. Agents that improve outer-membrane permeability and broad-spectrum beta-lactamase inhibitors may favorably impact difficult-to-treat (i.e., multidrug resistant) S. maltophilia infections.
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Affiliation(s)
- Amar Safdar
- Dept. of Infectious Diseases, Infection Control, and Employee Health, 402, The M. D. Anderson Cancer Center, University of Texas, 1515 Holcombe Blvd., Houston, TX 77030, USA.
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In Vitro Antibacterial Activity of a New Cephalosporin, FR295389, against IMP-type Metallo-β-lactamase-producers. J Antibiot (Tokyo) 2008; 61:36-9. [DOI: 10.1038/ja.2008.107] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Padayatti PS, Sheri A, Totir MA, Helfand MS, Carey MP, Anderson VA, Carey PR, Bethel CR, Bonomo RA, Buynak JD, van den Akker F. Rational design of a beta-lactamase inhibitor achieved via stabilization of the trans-enamine intermediate: 1.28 A crystal structure of wt SHV-1 complex with a penam sulfone. J Am Chem Soc 2007; 128:13235-42. [PMID: 17017804 PMCID: PMC2593906 DOI: 10.1021/ja063715w] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
beta-Lactamases are one of the major causes of antibiotic resistance in Gram negative bacteria. The continuing evolution of beta-lactamases that are capable of hydrolyzing our most potent beta-lactams presents a vexing clinical problem, in particular since a number of them are resistant to inhibitors. The efficient inhibition of these enzymes is therefore of great clinical importance. Building upon our previous structural studies that examined tazobactam trapped as a trans-enamine intermediate in a deacylation deficient SHV variant, we designed a novel penam sulfone derivative that forms a more stable trans-enamine intermediate. We report here the 1.28 A resolution crystal structure of wt SHV-1 in complex with a rationally designed penam sulfone, SA2-13. The compound is covalently bound to the active site of wt SHV-1 similar to tazobactam yet forms an additional salt-bridge with K234 and hydrogen bonds with S130 and T235 to stabilize the trans-enamine intermediate. Kinetic measurements show that SA2-13, once reacted with SHV-1 beta-lactamase, is about 10-fold slower at being released from the enzyme compared to tazobactam. Stabilizing the trans-enamine intermediate represents a novel strategy for the rational design of mechanism-based class A beta-lactamase inhibitors.
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Affiliation(s)
- Pius S. Padayatti
- Department of Biochemistry, Case Western Reserve University, Cleveland Ohio 44106
| | - Anjaneyulu Sheri
- Department of Chemistry, Southern Methodist University, Dallas TX 75275-0314
| | - Monica A. Totir
- Department of Chemistry, Case Western Reserve University, Cleveland Ohio 44106
| | - Marion S. Helfand
- Research Division, Louis Stokes Cleveland Veterans Affairs Medical Center, Cleveland Ohio 44106
| | - Marianne P. Carey
- Department of Biochemistry, Case Western Reserve University, Cleveland Ohio 44106
| | - Vernon A. Anderson
- Department of Biochemistry, Case Western Reserve University, Cleveland Ohio 44106
| | - Paul R. Carey
- Department of Biochemistry, Case Western Reserve University, Cleveland Ohio 44106
| | - Christopher R. Bethel
- Research Division, Louis Stokes Cleveland Veterans Affairs Medical Center, Cleveland Ohio 44106
| | - Robert A. Bonomo
- Research Division, Louis Stokes Cleveland Veterans Affairs Medical Center, Cleveland Ohio 44106
- Department of Pharmacology, Case Western Reserve University, Cleveland Ohio 44106
| | - John D. Buynak
- Department of Chemistry, Southern Methodist University, Dallas TX 75275-0314
| | - Focco van den Akker
- Department of Biochemistry, Case Western Reserve University, Cleveland Ohio 44106
- Corresponding author:
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Arnett SO, Gerratana B, Townsend CA. Rate-limiting steps and role of active site Lys443 in the mechanism of carbapenam synthetase. Biochemistry 2007; 46:9337-45. [PMID: 17658887 PMCID: PMC3198785 DOI: 10.1021/bi0618464] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Carbapenam synthetase (hereafter named CPS) catalyzes the formation of the beta-lactam ring in the biosynthetic pathway to (5R)-carbapen-2-em-3-carboxylate, the simplest of the carbapenem antibiotics. Kinetic studies showed remarkable tolerance to substrate stereochemistry in the turnover rate but did not distinguish between chemistry and a nonchemical step such as product release or conformational change as being rate-determining. Also, X-ray structural studies and modest sequence homology to beta-lactam synthetase, an enzyme that catalyzes the formation of a monocyclic beta-lactam ring in a similar ATP/Mg2+-dependent reaction, implicate K443 as an essential residue for substrate binding and intermediate stabilization. In these experiments, we use pH-rate profiles, deuterium solvent isotope effects, and solvent viscosity measurements to examine the rate-limiting step in this complex overall process of substrate adenylation and intramolecular ring formation. Mutagenesis and chemical rescue demonstrate that K443 is the general acid visible in the pH-rate profile of the wild-type CPS-catalyzed reaction. On the basis of these results, we propose a mechanism in which the rate-limiting step is beta-lactam ring formation coupled to a protein conformational change and underscore the role of K443 throughout the reaction.
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Affiliation(s)
| | | | - Craig A. Townsend
- To whom correspondence should be addressed. Phone: (410) 516-7444. Fax: (410) 261-1233.
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Wyrembak PN, Babaoglu K, Pelto RB, Shoichet BK, Pratt RF. O-aryloxycarbonyl hydroxamates: new beta-lactamase inhibitors that cross-link the active site. J Am Chem Soc 2007; 129:9548-9. [PMID: 17628063 DOI: 10.1021/ja072370u] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Pauline N Wyrembak
- Department of Chemistry, Wesleyan University, Middletown, Connecticut 06459, USA
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Totir MA, Padayatti PS, Helfand MS, Carey MP, Bonomo RA, Carey PR, van den Akker F. Effect of the inhibitor-resistant M69V substitution on the structures and populations of trans-enamine beta-lactamase intermediates. Biochemistry 2006; 45:11895-904. [PMID: 17002290 PMCID: PMC2596060 DOI: 10.1021/bi060990m] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The objective of this study was to determine the molecular factors that lead to beta-lactamase inhibitor resistance for the M69V variant in SHV-1 beta-lactamase. With mechanism-based inhibitors, the beta-lactamase forms an acyl-enzyme intermediate that consists of a trans-enamine derivative in the active site. This study focuses on these intermediates by introducing the E166A mutation that greatly retards deacylation. Thus, by comparing the properties of the E166A and M69V/E166A forms, we can explore the consequences of the resistance mutation at the level of the enamine acyl-enzyme forms. The reactions between the beta-lactamase and the inhibitors tazobactam, sulbactam, and clavulanic acid are followed in single crystals of the enzymes by using a Raman microscope. The resulting Raman difference spectroscopic data provide detailed information about conformational events involving the enamine species as well as an estimate of their populations. The Raman difference spectra for each of the inhibitors in the E166A and M69V/E166A variants are very similar. In particular, detailed analysis of the main enamine Raman vibration near 1595 cm(-1) reveals that the structure and flexibility of the enamine fragments are essentially identical for each of the three inhibitors in E166A and in the M69V/E166A double mutant. This finding is in accord with the X-ray-derived structures, presented herein at 1.6-1.75 A resolution, of the trans-enamine intermediates formed by the three inhibitors in M69V/E166A. However, a comparison of Raman results for M69V/E166A and E166A shows that the M69V mutation results in a 40%, 25%, and negligible reductions in the enamine population when the beta-lactamase crystals are soaked in 5 mM tazobactam, clavulanic acid, and sulbactam solutions, respectively. The levels of enamine from tazobactam and clavulanic acid can be increased by increasing the concentrations of inhibitor in the mother liquor. Thus, the sensitivity of population levels to the inhibitor concentration in the mother liquor focuses attention on the properties of the encounter complex preceding acylation. It is proposed that for small ligands, such as tazobactam, sulbactam, and clavulanic acid, the positioning of the lactam ring in the active site in the correct orientation for acylation is only one of a number of poorly defined conformations. For tazobactam and clavulanic acid, the correctly oriented encounter complex is even less likely in the M69V variant, leading to a reduction in the level of inhibition of the enzyme via formation of the acyl-enzyme intermediate and the onset of resistance. Analysis of the X-ray structures of the three intermediates in M69V/E166A demonstrates that, compared to the structures for the E166A form, the oxyanion hole becomes smaller, providing one explanation for why acylation may be less efficient following the M69V substitution.
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Affiliation(s)
- Monica A Totir
- Department of Biochemistry, Case Western Reserve University, Cleveland, Ohio 44106, USA
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28
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Phillips OA. β-Lactamase inhibitors: a survey of the patent literature 2000 – 2004. Expert Opin Ther Pat 2006. [DOI: 10.1517/13543776.16.3.319] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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29
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Buynak JD. Understanding the longevity of the beta-lactam antibiotics and of antibiotic/beta-lactamase inhibitor combinations. Biochem Pharmacol 2005; 71:930-40. [PMID: 16359643 DOI: 10.1016/j.bcp.2005.11.012] [Citation(s) in RCA: 71] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2005] [Revised: 11/02/2005] [Accepted: 11/10/2005] [Indexed: 10/25/2022]
Abstract
Microbial resistance necessitates the search for new targets and new antibiotics. However, it is likely that resistance problems will eventually threaten these new products and it may, therefore, be instructive to review the successful employment of beta-lactam antibiotic/beta-lactamase inhibitor combinations to combat penicillin resistance. These combination drugs have proven successful for more than two decades, with inhibitor resistance still being relatively rare. The beta-lactamase inhibitors are mechanism-based irreversible inactivators. The ability of the inhibitors to avoid resistance may be due to the structural similarities between the substrate and inhibitor.
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Affiliation(s)
- John D Buynak
- Department of Chemistry, Southern Methodist University, Dallas, TX 75275-0314, USA.
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Padayatti PS, Helfand MS, Totir MA, Carey MP, Carey PR, Bonomo RA, van den Akker F. High resolution crystal structures of the trans-enamine intermediates formed by sulbactam and clavulanic acid and E166A SHV-1 {beta}-lactamase. J Biol Chem 2005; 280:34900-7. [PMID: 16055923 DOI: 10.1074/jbc.m505333200] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Antibiotic resistance mediated by constantly evolving beta-lactamases is a serious threat to human health. The mechanism of inhibition of these enzymes by therapeutic beta-lactamase inhibitors is probed using a novel approach involving Raman microscopy and x-ray crystallography. We have presented here the high resolution crystal structures of the beta-lactamase inhibitors sulbactam and clavulanic acid bound to the deacylation-deficient E166A variant of SHV-1 beta-lactamase. Our previous Raman measurements have identified the trans-enamine species for both inhibitors and were used to guide the soaking time and concentration to achieve full occupancy of the active sites. The two inhibitor-bound x-ray structures revealed a linear trans-enamine intermediate covalently attached to the active site Ser-70 residue. This intermediate was thought to play a key role in the transient inhibition of class A beta-lactamases. Both the Raman and x-ray data indicated that the clavulanic acid intermediate is decarboxylated. When compared with our previously determined tazobactam-bound inhibitor structure, our new inhibitor-bound structures revealed an increased disorder in the tail region of the inhibitors as well as in the enamine skeleton. The x-ray crystallographic observations correlated with the broadening of the O-C=C-N (enamine) symmetric stretch Raman band near 1595 cm(-1). Band broadening in the sulbactam and clavulanic acid inter-mediates reflected a heterogeneous conformational population that results from variations of torsional angles in the O-(C=O)-C=C=NH-C skeleton. These observations led us to conclude that the conformational stability of the trans-enamine form is critical for their transient inhibitory efficacy.
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Affiliation(s)
- Pius S Padayatti
- Department of Biochemistry, Department of Chemistry, Case Western Reserve University, Cleveland, Ohio 44106, USA
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Fisher JF, Meroueh SO, Mobashery S. Bacterial resistance to beta-lactam antibiotics: compelling opportunism, compelling opportunity. Chem Rev 2005; 105:395-424. [PMID: 15700950 DOI: 10.1021/cr030102i] [Citation(s) in RCA: 684] [Impact Index Per Article: 36.0] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Affiliation(s)
- Jed F Fisher
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, Indiana 46556, USA
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