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Shintani M, Suzuki H, Nojiri H, Suzuki M. Reconsideration of the previously classified incompatibility groups of plasmids, IncP-1 and IncP-11. Environ Microbiol 2023. [PMID: 36744408 DOI: 10.1111/1462-2920.16345] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2022] [Accepted: 02/01/2023] [Indexed: 02/07/2023]
Abstract
This study presents the reassessment of earlier published data with reference to the article published in Environmental Microbiology entitled 'IncP-type plasmids carrying genes for antibiotic resistance or aromatic compound degradation are prevalent in sequenced Aromatoleum and Thauera strains' by Lo et al. This correspondence clarifies misperceptions of plasmids classified under incompatibility (Inc) groups IncP-1 and IncP-11.
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Affiliation(s)
- Masaki Shintani
- Department of Engineering, Graduate School of Integrated Science and Technology, Shizuoka University, Hamamatsu, Shizuoka, Japan.,Research Institute of Green Science and Technology, Shizuoka University, Hamamatsu, Shizuoka, Japan.,Japan Collection of Microorganisms, RIKEN BioResource Research Center, Ibaraki, Japan
| | - Haruo Suzuki
- Faculty of Environment and Information Studies, Keio University, Fujisawa, Kanagawa, Japan
| | - Hideaki Nojiri
- Agro-Biotechnology Research Center (AgTECH), Graduate School of Agricultural and Life Sciences, The University of Tokyo, Tokyo, Japan
| | - Masato Suzuki
- Antimicrobial Resistance Research Center, National Institute of Infectious Diseases, Tokyo, Japan
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2
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Najjuka CF, Kateete DP, Lodiongo DK, Mambo O, Mocktar C, Kayondo W, Baluku H, Kajumbula HM, Essack SY, Joloba ML. Prevalence of plasmid-mediated AmpC beta-lactamases in Enterobacteria isolated from urban and rural folks in Uganda. AAS Open Res 2020; 3:62. [PMID: 34549164 PMCID: PMC8422338 DOI: 10.12688/aasopenres.13165.1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/20/2020] [Indexed: 01/13/2023] Open
Abstract
Background: AmpC beta-lactamase-producing bacteria are associated with increased resistance to third-generation cephalosporins. Here, we describe plasmid-mediated AmpC beta-lactamase-producing enterobacteria isolated from urban and rural dwellers in Uganda. Methods: Stool and urine from 1,448 individuals attending outpatient clinics in Kampala and two rural districts in central Uganda were processed for isolation of Escherichia coli and Klebsiella. Following antibiotic susceptibility testing, cefoxitin resistant isolates, and amoxicillin/clavulanate resistant but cefoxitin susceptible isolates, were tested for AmpC beta-lactamase production using the cefoxitin-cloxacillin double-disc synergy test. Carriage of plasmid-mediated AmpC beta-lactamase-encoding genes (pAmpC) and extended spectrum beta-lactamase (ESBL) encoding genes was determined by PCR. Results: Nine hundred and thirty E. coli and 55 Klebsiella were recovered from the cultured samples, yielding 985 isolates investigated (one per participant). One hundred and twenty-nine isolates (13.1%, 129/985) were AmpC beta-lactamase producers, of which 111 were molecularly characterized for pAmpC and ESBL gene carriage. pAmpC genes were detected in 60% (67/111) of the AmpC beta-lactamase producers; pAmpC genes were also detected in 18 AmpC beta-lactamase non-producers and in 13 isolates with reduced susceptibility to third-generation cephalosporins, yielding a total of 98 isolates that carried pAmpC genes. Overall, the prevalence of pAmpC genes in cefoxitin resistant and/or amoxicillin/clavulanate resistant E. coli and Klebsiella was 59% (93/157) and 26.1% (5/23), respectively. The overall prevalence of pAmpC-positive enterobacteria was 10% (98/985); 16.4% (45/274) in Kampala, 6.2% (25/406) Kayunga, and 9.2% (28/305) Mpigi. Ciprofloxacin use was associated with carriage of pAmpC-positive bacteria while residing in a rural district was associated with protection from carriage of pAmpC-positive bacteria. Conclusion: pAmpC beta-lactamase producing enterobacteria are prevalent in urban and rural dwellers in Uganda; therefore, cefoxitn should be considered during routine susceptibility testing in this setting.
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Affiliation(s)
- Christine F Najjuka
- Department of Medical Microbiology, Makerere University College of Health Sciences, Kampala, Uganda
| | - David Patrick Kateete
- Department of Medical Microbiology, Makerere University College of Health Sciences, Kampala, Uganda
- Department of Immunology & Molecular Biology, Makerere University College of Health Sciences, Kampala, Uganda
| | - Dennis K Lodiongo
- Department of Medical Microbiology, Makerere University College of Health Sciences, Kampala, Uganda
- Ministry of Health Public Health Laboratory, National Blood Bank and Transfusion services Centre, Juba, Sudan
| | - Obede Mambo
- Department of Medical Microbiology, Makerere University College of Health Sciences, Kampala, Uganda
- Rumbek Health Science Institute, Lakes State, Sudan
| | - Chunderika Mocktar
- Antimicrobial Research Unit, School of Health Sciences, University of KwaZulu Natal, Westville, Durban, South Africa
| | - William Kayondo
- Makerere University Walter Reed Project, Box 16524, Kampala, Uganda
| | - Hannington Baluku
- Department of Medical Microbiology, Makerere University College of Health Sciences, Kampala, Uganda
| | - Henry M Kajumbula
- Department of Medical Microbiology, Makerere University College of Health Sciences, Kampala, Uganda
| | - Sabiha Y Essack
- Antimicrobial Research Unit, School of Health Sciences, University of KwaZulu Natal, Westville, Durban, South Africa
| | - Moses L Joloba
- Department of Medical Microbiology, Makerere University College of Health Sciences, Kampala, Uganda
- Department of Immunology & Molecular Biology, Makerere University College of Health Sciences, Kampala, Uganda
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3
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Ramirez MS, Bonomo RA, Tolmasky ME. Carbapenemases: Transforming Acinetobacter baumannii into a Yet More Dangerous Menace. Biomolecules 2020; 10:biom10050720. [PMID: 32384624 PMCID: PMC7277208 DOI: 10.3390/biom10050720] [Citation(s) in RCA: 111] [Impact Index Per Article: 27.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2020] [Revised: 04/27/2020] [Accepted: 04/29/2020] [Indexed: 02/07/2023] Open
Abstract
Acinetobacter baumannii is a common cause of serious nosocomial infections. Although community-acquired infections are observed, the vast majority occur in people with preexisting comorbidities. A. baumannii emerged as a problematic pathogen in the 1980s when an increase in virulence, difficulty in treatment due to drug resistance, and opportunities for infection turned it into one of the most important threats to human health. Some of the clinical manifestations of A. baumannii nosocomial infection are pneumonia; bloodstream infections; lower respiratory tract, urinary tract, and wound infections; burn infections; skin and soft tissue infections (including necrotizing fasciitis); meningitis; osteomyelitis; and endocarditis. A. baumannii has an extraordinary genetic plasticity that results in a high capacity to acquire antimicrobial resistance traits. In particular, acquisition of resistance to carbapenems, which are among the antimicrobials of last resort for treatment of multidrug infections, is increasing among A. baumannii strains compounding the problem of nosocomial infections caused by this pathogen. It is not uncommon to find multidrug-resistant (MDR, resistance to at least three classes of antimicrobials), extensively drug-resistant (XDR, MDR plus resistance to carbapenems), and pan-drug-resistant (PDR, XDR plus resistance to polymyxins) nosocomial isolates that are hard to treat with the currently available drugs. In this article we review the acquired resistance to carbapenems by A. baumannii. We describe the enzymes within the OXA, NDM, VIM, IMP, and KPC groups of carbapenemases and the coding genes found in A. baumannii clinical isolates.
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Affiliation(s)
- Maria Soledad Ramirez
- Center for Applied Biotechnology Studies, Department of Biological Science, California State University Fullerton, Fullerton, CA 92831, USA;
| | - Robert A. Bonomo
- Medical Service and GRECC, Louis Stokes Cleveland Department of Veterans Affairs Medical Center, Cleveland, OH 44106, USA;
- Departments of Medicine, Pharmacology, Molecular Biology and Microbiology, Biochemistry, Proteomics and Bioinformatics; Case Western Reserve University School of Medicine, Cleveland, OH 44106, USA
- WRU-Cleveland VAMC Center for Antimicrobial Resistance and Epidemiology (Case VA CARES), Cleveland, OH 44106, USA
| | - Marcelo E. Tolmasky
- Center for Applied Biotechnology Studies, Department of Biological Science, California State University Fullerton, Fullerton, CA 92831, USA;
- Correspondence: ; Tel.: +657-278-5263
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4
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Characterization of a Carbapenem-Hydrolyzing Enzyme, PoxB, in Pseudomonas aeruginosa PAO1. Antimicrob Agents Chemother 2015; 60:936-45. [PMID: 26621621 DOI: 10.1128/aac.01807-15] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2015] [Accepted: 11/18/2015] [Indexed: 12/15/2022] Open
Abstract
Pseudomonas aeruginosa is an opportunistic pathogen often associated with severe and life-threatening infections that are highly impervious to treatment. This microbe readily exhibits intrinsic and acquired resistance to varied antimicrobial drugs. Resistance to penicillin-like compounds is commonplace and provided by the chromosomal AmpC β-lactamase. A second, chromosomally encoded β-lactamase, PoxB, has previously been reported in P. aeruginosa. In the present work, the contribution of this class D enzyme was investigated using a series of clean in-frame ampC, poxB, and oprD deletions, as well as complementation by expression under the control of an inducible promoter. While poxB deletions failed to alter β-lactam sensitivities, expression of poxB in ampC-deficient backgrounds decreased susceptibility to both meropenem and doripenem but had no effect on imipenem, penicillin, and cephalosporin MICs. However, when expressed in an ampCpoxB-deficient background, that additionally lacked the outer membrane porin-encoding gene oprD, PoxB significantly increased the imipenem as well as the meropenem and doripenem MICs. Like other class D carbapenem-hydrolyzing β-lactamases, PoxB was only poorly inhibited by class A enzyme inhibitors, but a novel non-β-lactam compound, avibactam, was a slightly better inhibitor of PoxB activity. In vitro susceptibility testing with a clinical concentration of avibactam, however, failed to reduce PoxB activity against the carbapenems. In addition, poxB was found to be cotranscribed with an upstream open reading frame, poxA, which itself was shown to encode a 32-kDa protein of yet unknown function.
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5
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Isolation of NDM-1-producing multidrug-resistant Pseudomonas putida from a paediatric case of acute gastroenteritis, India. New Microbes New Infect 2015; 5:5-9. [PMID: 25893095 PMCID: PMC4398820 DOI: 10.1016/j.nmni.2015.02.002] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2014] [Revised: 02/06/2015] [Accepted: 02/18/2015] [Indexed: 11/24/2022] Open
Abstract
Pseudomonas putida is an uncommon opportunistic pathogen, usually susceptible to antimicrobial agents. Data concerning resistance to antimicrobial agents in clinical P. putida isolates are limited. To the best of our knowledge we report for the first time the isolation of NDM-1-producing multidrug-resistant P. putida from a case of acute gastroenteritis. The isolate showed resistance to a wide range of antimicrobials, including fluoroquinolones, third-generation cephalosporins and carbapenems. The isolate also exhibited multiple mutations in the quinolone resistance determining region and showed the presence of qepA, bla TEM , bla OXA1 and bla OXA7 genes. The present study highlights the importance of looking for the relatively rare aetiological agents in clinical samples that do not yield common pathogens.
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6
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First Report of OXA-4, an ESBL Isolated from Pseudomonas aeruginosa a South Indian Strain. Indian J Microbiol 2014; 53:308-14. [PMID: 24426128 DOI: 10.1007/s12088-012-0326-3] [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: 11/04/2009] [Accepted: 03/22/2010] [Indexed: 10/27/2022] Open
Abstract
The OXA-type β-lactamases are so named because of their oxacillin-hydrolyzing abilities. In this study we characterize an extended spectrum β-lactamase, designated OXA-4, produced by a clinical isolate of Pseudomonas aeruginosa. ESBL production was detected by double disk synergy test. The P. aeruginosa isolate was obtained from endotracheal suction tip of 84 years old male patient diagnosed with CVA and hypertension. ESBL producing OXA β-lactamases was detected by PCR with primers specific to the conserved regions of the coding genes. Iso electric focusing was done to confirm the significance, sequencing the amplified product was also done. In the phenotypic identification, the strain was highly resistant to third generation cephalosporins and also to imipenem. The PCR amplified product for OXA β-lactamase was viewed at 919 bp. The pI point for the same was identified at 7.2. With the help of sequencing the amplified OXA β-lactamase was identified as OXA-4 gene. Here we report P. aeruginosa producing OXA-4 ESBL for the first time in the Indian subcontinent.
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7
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Abstract
β-Lactamases can be named on the basis of molecular characteristics or functional properties. Molecular classes A, B, C, and D define an enzyme according to amino acid sequence and conserved motifs. Functional groups 1, 2, and 3 are used to assign a clinically useful description to a family of enzymes, with subgroups designated according to substrate and inhibitor profiles. In addition, other designations are used to define the functionality of specific subgroups, such as extended-spectrum β-lactamases, or ESBLs, and inhibitor-resistant TEM, or IRT, β-lactamases. None of these systems provides an unambiguous description of this versatile set of enzymes. A proposed classification system involving microbiological, molecular, and biochemical properties is described, based on the traditional classes A, B, C, and D and functional groups 1, 2, and 3 designations.
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Affiliation(s)
- Karen Bush
- Department of Molecular and Cellular Biochemistry, Indiana University Bloomington, Simon Hall 102B, 212 S. Hawthorne Dr., Bloomington, IN, 47405, USA.
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8
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Olowe O, Aboderin B. Detection of Extended Spectrum β-Lactamase Producing Strains of (Escherichia coli) and (Klebsiella sp.) in a Tertiary Health Centre in Ogun State. ACTA ACUST UNITED AC 2010. [DOI: 10.3923/ijtmed.2010.62.64] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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9
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Kinetic parameters of efflux of penicillins by the multidrug efflux transporter AcrAB-TolC of Escherichia coli. Antimicrob Agents Chemother 2010; 54:1800-6. [PMID: 20160052 DOI: 10.1128/aac.01714-09] [Citation(s) in RCA: 69] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
Abstract
The multidrug efflux transporter AcrAB-TolC is known to pump out a diverse range of antibiotics, including beta-lactams. However, the kinetic constants of the efflux process, needed for the quantitative understanding of resistance, were not available until those accompanying the efflux of some cephalosporins were recently determined by combining efflux with the hydrolysis of drugs by the periplasmic beta-lactamase. In the present study we extended this approach to the study of a wide range of penicillins, from ampicillin and penicillin V to ureidopenicillins and isoxazolylpenicillins, by combining efflux with hydrolysis with the OXA-7 penicillinase. We found that the penicillins had a much stronger apparent affinity to AcrB and higher maximum rates of efflux than the cephalosporins. All penicillins showed strong positive cooperativity kinetics for export. The kinetic constants obtained were validated, as the MICs theoretically predicted on the basis of efflux and hydrolysis kinetics were remarkably similar to the observed MICs (except for the isoxazolylpenicillins). Surprisingly, however, the efflux kinetics of cloxacillin, for example, whose MIC decreased 512-fold in Escherichia coli upon the genetic deletion of the acrB gene, were quite similar to those of ampicillin, whose MIC decreased only 2-fold with the same treatment. Analysis of this phenomenon showed that the extensive decrease in the MIC for the acrB mutant is primarily due to the low permeation of the drug and that comparison of the MICs between the parent and the acrB strains is a very poor measure of the ability of AcrB to pump a drug out.
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10
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Abstract
This review focuses on the era of antibiosis that led to a better understanding of bacterial morphology, in particular the cell wall component peptidoglycan. This is an effort to take readers on a tour de force from the concept of antibiosis, to the serendipity of antibiotics, evolution of beta-lactam development, and the molecular biology of antibiotic resistance. These areas of research have culminated in a deeper understanding of microbiology, particularly in the area of bacterial cell wall synthesis and recycling. In spite of this knowledge, which has enabled design of new even more effective therapeutics to combat bacterial infection and has provided new research tools, antibiotic resistance remains a worldwide health care problem.
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Affiliation(s)
- Kok-Fai Kong
- Department of Biological Sciences, Florida International University, Miami, FL, USA
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11
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Abstract
Class D beta-lactamase-mediated resistance to beta-lactams has been increasingly reported during the last decade. Those enzymes also known as oxacillinases or OXAs are widely distributed among Gram negatives. Genes encoding class D beta-lactamases are known to be intrinsic in many Gram-negative rods, including Acinetobacter baumannii and Pseudomonas aeruginosa, but play a minor role in natural resistance phenotypes. The OXAs (ca. 150 variants reported so far) are characterized by an important genetic diversity and a great heterogeneity in terms of beta-lactam hydrolysis spectrum. The acquired OXAs possess either a narrow spectrum or an expanded spectrum of hydrolysis, including carbapenems in several instances. Acquired class D beta-lactamase genes are mostly associated to class 1 integron or to insertion sequences.
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12
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Bonomo RA, Szabo D. Mechanisms of multidrug resistance in Acinetobacter species and Pseudomonas aeruginosa. Clin Infect Dis 2006; 43 Suppl 2:S49-56. [PMID: 16894515 DOI: 10.1086/504477] [Citation(s) in RCA: 478] [Impact Index Per Article: 26.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
Abstract
Acinetobacter species and Pseudomonas aeruginosa are noted for their intrinsic resistance to antibiotics and for their ability to acquire genes encoding resistance determinants. Foremost among the mechanisms of resistance in both of these pathogens is the production of beta -lactamases and aminoglycoside-modifying enzymes. Additionally, diminished expression of outer membrane proteins, mutations in topoisomerases, and up-regulation of efflux pumps play an important part in antibiotic resistance. Unfortunately, the accumulation of multiple mechanisms of resistance leads to the development of multiply resistant or even "panresistant" strains.
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Affiliation(s)
- Robert A Bonomo
- Louis Stokes Cleveland Dept. of Veterans Affairs Medical Center, Section of Infectious Diseases, Cleveland, Ohio 44106, USA.
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13
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14
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Chmelnitsky I, Carmeli Y, Leavitt A, Schwaber MJ, Navon-Venezia S. CTX-M-2 and a new CTX-M-39 enzyme are the major extended-spectrum beta-lactamases in multiple Escherichia coli clones isolated in Tel Aviv, Israel. Antimicrob Agents Chemother 2006; 49:4745-50. [PMID: 16251320 PMCID: PMC1280129 DOI: 10.1128/aac.49.11.4745-4750.2005] [Citation(s) in RCA: 52] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The rate of occurrence of the extended-spectrum beta-lactamase (ESBL)-producing phenotype among Escherichia coli isolates in Tel Aviv is 12% (22). The aim of this study was to understand the molecular epidemiology of E. coli ESBL producers and to identify the ESBL genes carried by them. We studied 20 single-patient ESBL-producing E. coli clinical isolates. They comprised 11 distinct nonrelated pulsed-field gel electrophoresis (PFGE) genotypes: six isolates belonged to the same PFGE clone, four other clones included two isolates each, and six unrelated clones included only one isolate. All isolates produced various beta-lactamases with pIs ranging from 5.2 to 8.2, varying within similar PFGE clones. The most prevalent ESBL gene was bla(CTX-M); 16 isolates carried bla(CTX-M-2) and three carried a new ESBL gene designated bla(CTX-M-39). Three strains carried bla(SHV) (two bla(SHV-12) and one bla(SHV-5)), and two strains carried inhibitor-resistant ESBL genes, bla(TEM-33) and bla(TEM-30); 18 strains carried bla(TEM-1) and eight strains carried bla(OXA-2). Plasmid mapping and Southern blot analysis with a CTX-M-2 probe demonstrated that bla(CTX-M-2) is plasmid borne. The wide dissemination of ESBLs among E. coli isolates in our institution is partly related to clonal spread, but more notably to various plasmid-associated ESBL genes, occurring in multiple clones, wherein the CTX-M gene family appears almost uniformly. We report here a new CTX-M gene, designated bla(CTX-M-39), which revealed 99% homology with bla(CTX-M-26), with a substitution of arginine for glutamine at position 225.
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Affiliation(s)
- Inna Chmelnitsky
- Division of Epidemiology and Laboratory for Molecular Epidemiology and Antibiotic Research, Tel Aviv Sourasky Medical Center, Sackler Faculty of Medicine, Tel Aviv University, Israel
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15
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Kong KF, Jayawardena SR, Del Puerto A, Wiehlmann L, Laabs U, Tümmler B, Mathee K. Characterization of poxB, a chromosomal-encoded Pseudomonas aeruginosa oxacillinase. Gene 2005; 358:82-92. [PMID: 16120476 DOI: 10.1016/j.gene.2005.05.027] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2004] [Revised: 04/11/2005] [Accepted: 05/17/2005] [Indexed: 11/29/2022]
Abstract
Pseudomonas aeruginosa is the major pathogen associated with morbidity and mortality of patients with cystic fibrosis. One of the reasons for the failure of beta-lactam antibiotic regimens appears to be mediated by de-regulation of the ampC gene, encoding the chromosomal Ambler's Class C beta-lactamase. Currently, the AmpC is the only known chromosomal beta-lactamase whose expression is regulated by a transcriptional regulator, AmpR. We generated an ampC mutation in the prototypic P. aeruginosa strain PAO1. The mutation in ampC did not abolish the beta-lactamase activity entirely suggesting the expression of yet another unreported beta-lactamase. Our genomic analysis revealed the presence of an open reading frame encoding a protein with high homology to the Class D beta-lactamases, commonly known as oxacillinases. The gene was named poxB for Pseudomonas oxacillinase. Cloning and expression of poxB in Escherichia coli conferred beta-lactam resistance to the host. We detected the presence of poxB both in clinical and environmental isolates. Our studies show that P. aeruginosa possesses two beta-lactamases, AmpC and PoxB, which contribute to its resistance against a wide spectrum of beta-lactam antibiotics.
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Affiliation(s)
- Kok-Fai Kong
- Department of Biological Sciences, Florida International University, University Park, Miami, FL 33199, USA
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16
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Alvarez M, Tran JH, Chow N, Jacoby GA. Epidemiology of conjugative plasmid-mediated AmpC beta-lactamases in the United States. Antimicrob Agents Chemother 2004; 48:533-7. [PMID: 14742206 PMCID: PMC321551 DOI: 10.1128/aac.48.2.533-537.2004] [Citation(s) in RCA: 137] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
A sample of 752 resistant Klebsiella pneumoniae, Klebsiella oxytoca, and Escherichia coli strains from 70 sites in 25 U.S. states and the District of Columbia was examined for transmissibility of resistance to ceftazidime and the nature of the plasmid-mediated beta-lactamase involved. Fifty-nine percent of the K. pneumoniae, 24% of the K. oxytoca, and 44% of the E. coli isolates transferred resistance to ceftazidime. Plasmids encoding AmpC-type beta-lactamase were found in 8.5% of the K. pneumoniae samples, 6.9% of the K. oxytoca samples, and 4% of the E. coli samples, at 20 of the 70 sites and in 10 of the 25 states. ACT-1 beta-lactamase was found at eight sites, four of which were near New York City, where the ACT-1 enzyme was first discovered; ACT-1 beta-lactamase was also found in Massachusetts, Pennsylvania, and Virginia. FOX-5 beta-lactamase was also found at eight sites, mainly in southeastern states but also in New York. Two E. coli strains produced CMY-2, and one K. pneumoniae strain produced DHA-1 beta-lactamase. Pulsed-field gel electrophoresis and plasmid analysis suggested that AmpC-mediated resistance spread both by strain and plasmid dissemination. All AmpC beta-lactamase-containing isolates were resistant to cefoxitin, but so were 11% of strains containing transmissible SHV- and TEM-type extended-spectrum beta-lactamases. A beta-lactamase inhibitor test was helpful in distinguishing the two types of resistance but was not definitive since 24% of clinical isolates producing AmpC beta-lactamase had a positive response to clavulanic acid. Coexistence of AmpC and extended-spectrum beta-lactamases was the main reason for these discrepancies. Plasmid-mediated AmpC-type enzymes are thus responsible for an appreciable fraction of resistance in clinical isolates of Klebsiella spp. and E. coli, are disseminated around the United States, and are not so easily distinguished from other enzymes that mediate resistance to oxyimino-beta-lactams.
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Affiliation(s)
- M Alvarez
- Lahey Clinic, Burlington, and Edith Nourse Rogers Memorial Veterans Hospital, Bedford, Massachusetts, USA
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17
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Abstract
The NPS-1 and TLE-1 beta-lactamase genes were cloned and sequenced. NPS-1 differed from LCR-1 beta-lactamase in 8 of 260 amino acids. TLE-1 differed from TEM-1 by a single Asp(115)-->Gly substitution and has been renamed TEM-90.
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Affiliation(s)
- H Pai
- Division of Infectious Disease, College of Medicine, Dankook University, Chonan, Korea
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18
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Danel F, Frère JM, Livermore DM. Evidence of dimerisation among class D beta-lactamases: kinetics of OXA-14 beta-lactamase. BIOCHIMICA ET BIOPHYSICA ACTA 2001; 1546:132-42. [PMID: 11257516 DOI: 10.1016/s0167-4838(01)00133-9] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
OXA-14 enzyme, a class D beta-lactamase, gave biphasic kinetics with all penicillin and cephalosporin substrates tested, such that the catalytic rate declined more swiftly than was explicable by substrate depletion. This biphasic behaviour was independent of temperature or extraneous protein but was lost if the enzyme was diluted to occupy almost the total assay volume before addition of a small amount of concentrated substrate. The presence of substrate could partially protect the enzyme against conversion to the less active form, with protection greatest at substrate concentration above the K(m). These observations are compatible with the hypothesis that the biphasic kinetics depended on the enzyme existing as a highly active dimer at high concentration and as a less active monomer at low concentration. Direct evidence supporting this hypothesis came from the observation that gel exclusion chromatography indicated a higher molecular weight for concentrated enzyme than for dilute. Biphasic kinetics are not so universal for different substrates amongst beta-lactamases (OXA-10, -11, -13, -16 and -17) that differ from OXA-14 by only one to two amino acid substitutions. It may be that the monomer:dimer equilibrium is more rapidly achieved with these enzymes than with OXA-14, or that the kinetic properties of the dimers and monomers of these enzymes are similar, masking any biphasic trait.
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Affiliation(s)
- F Danel
- Department of Medical Microbiology, St. Bartholomew's and the Royal London School of Medicine and Dentistry, Turner Street, London E1 2AD, UK.
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Leflon-Guibout V, Speldooren V, Heym B, Nicolas-Chanoine M. Epidemiological survey of amoxicillin-clavulanate resistance and corresponding molecular mechanisms in Escherichia coli isolates in France: new genetic features of bla(TEM) genes. Antimicrob Agents Chemother 2000; 44:2709-14. [PMID: 10991849 PMCID: PMC90140 DOI: 10.1128/aac.44.10.2709-2714.2000] [Citation(s) in RCA: 61] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Amoxicillin-clavulanate resistance (MIC >16 microg/ml) and the corresponding molecular mechanisms were prospectively studied in Escherichia coli over a 3-year period (1996 to 1998) in 14 French hospitals. The overall frequency of resistant E. coli isolates remained stable at about 5% over this period. The highest frequency of resistant isolates (10 to 15%) was observed, independently of the year, among E. coli isolated from lower respiratory tract samples, and the isolation rate of resistant strains was significantly higher in surgical wards than in medical wards in 1998 (7.8 versus 2.8%). The two most frequent mechanisms of resistance for the 3 years were the hyperproduction of the chromosomal class C beta-lactamase (48, 38.4, and 39.7%) and the production of inhibitor-resistant TEM (IRT) enzymes (30.4, 37.2, and 41.2%). By using the single-strand conformational polymorphism-PCR technique and sequencing methods, we determined that 59 IRT enzymes corresponded to previously described IRT enzymes whereas 8 were new. Three of these new enzymes derived from TEM-1 by only one amino acid substitution (Ser130Gly, Arg244Gly, and Asn276Asp), whereas three others derived by two amino acid substitutions (Met69Leu and Arg244Ser, Met69Leu and Ile127Val, and Met69Val and Arg275Gln). The two remaining new IRTs showed three amino acid substitutions (Met69Val, Trp165Arg, and Asn276Asp and Met69Ile, Trp165Cys, and Arg275Gln). New genetic features were also found in bla(TEM) genes, namely, bla(TEM-1B) with either the promoters Pa and Pb, P4, or a promoter displaying a C-->G transversion at position 3 of the -35 consensus sequence and new bla(TEM) genes, notably one encoding TEM-1 but possessing the silent mutations originally described in bla(TEM-2) and then in some bla(TEM)-encoding IRT enzymes.
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Affiliation(s)
- V Leflon-Guibout
- Microbiology Department, Hôpital Ambroise-Paré, Université Paris V, 92100 Boulogne-Billancourt, France
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20
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Marumo K, Nakamura Y. Isolation of Pseudomonas aeruginosa producing OXA-4 beta-lactamase in a Japanese hospital in 1996. J Infect Chemother 2000; 6:184-7. [PMID: 11810562 DOI: 10.1007/s101560070020] [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: 03/31/2000] [Accepted: 07/25/2000] [Indexed: 11/25/2022]
Abstract
One-hundred and fifty isolates of Pseudomonas aeruginosa were collected from different patients' specimens at Showa University Fujigaoka Hospital between April and August 1996. The 23 isolates resistant to piperacillin (minimum inhibitory concentration, >or=100 microg/ml) were widely distributed in the hospital wards. Using polymerase chain reaction-single-strand conformation polymorphism (PCR-SSCP) and isoelectric focusing (IEF) methods, we detected OXA-4 beta-lactamase hydrolyzing penams in 4 of the resistant isolates (17%) with O-serotype E. However, no other external beta-lactamase was detected by the IEF method. The hybridization results showed that the OXA-4 genes were located in chromosome, but not in plasmid. Furthermore, the isolation rate was significantly lower than that found between 1992 and 1993 (61%; P < 0.01; chi2-test), suggesting a decreased rate of hospital infection caused by P. aeruginosa producing the OXA-4 enzyme.
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Affiliation(s)
- K Marumo
- Department of Clinical Pathology, Showa University Fujigaoka Hospital, 1-30 Fujigaoka, Aoba-ku, Yokohama 227-8501, Japan.
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21
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Abstract
Cycling of currently available antibiotics to reduce resistance is an attractive concept. For cycling strategies to be successful, their implementation must have a demonstrable impact on the prevalence of resistance determinants already dispersed throughout the hospital and associated healthcare facilities. While antibiotic use in hospitals clearly constitutes a stimulus for the emergence of resistance, it is by no means the only important factor. The incorporation of resistance determinants into potentially stable genetic structures, including bacteriophages, plasmids, transposons, and the more newly discovered movable elements termed integrons and gene cassettes, forces some degree of skepticism about the potential for such strategies in institutions where resistance determinants are already prevalent. In particular, the expanding role of integrons may pose an ultimate threat to formulary manipulations such as cycling. Despite these concerns, the crisis posed by antimicrobial resistance warrants investigation of any strategy with the potential for reducing the prevalence of resistance. Over the next decade, new studies with carefully designed outcomes should determine the utility of antibiotic cycling as one control measure for nosocomial resistance.
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Affiliation(s)
- J F John
- Division of Allergy, Immunology, and Infectious Diseases, Robert Wood Johnson Medical School, New Brunswick, New Jersey 08903-0019, USA
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22
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Ehrhardt AF, Sanders CC, Moland ES. Use of an isogenic Escherichia coli panel to design tests for discrimination of beta-lactamase functional groups of Enterobacteriaceae. Antimicrob Agents Chemother 1999; 43:630-3. [PMID: 10049278 PMCID: PMC89171 DOI: 10.1128/aac.43.3.630] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/1998] [Accepted: 12/14/1998] [Indexed: 11/20/2022] Open
Abstract
A study was designed to determine if an isogenic panel of Escherichia coli strains containing many different beta-lactamases could be used for the preliminary screening of a large number of beta-lactam agents to identify which might be most useful in the development of a definitive test for specific beta-lactamases found among the members of family Enterobacteriaceae. The susceptibilities of 46 strains, comprising the isogenic panel, to expanded-spectrum cephalosporins, cephamycins, and aztreonam were determined in the presence and absence of beta-lactamase inhibitors in broth microdilution tests. The results indicated that strains producing extended-spectrum beta-lactamases (ESBLs) could be distinguished from strains producing other Bush-Jacoby-Medeiros functional group 2 or group 1 beta-lactamases. For strains producing group 1 beta-lactamases, cefpodoxime and ceftazidime MICs were > or = 4 micrograms/ml and addition of clavulanate did not reduce the MICs more than fourfold. For strains producing group 2 enzymes other than ESBLs, cefpodoxime and ceftazidime MICs were < or = 2 micrograms/ml. With a single exception (ceftazidime for the strain producing SHV-3), among strains producing ESBLs, cefpodoxime and ceftazidime MICs were > or = 4 micrograms/ml and addition of clavulanate reduced the MICs by more than eightfold. Cephamycins could also be used to discriminate between strains producing group 1 beta-lactamases and ESBLs, since only the former required cefotetan concentrations as high as 8 micrograms/ml or cefoxitin concentrations of > 16 micrograms/ml for inhibition. Other cephalosporins provided some discrimination between the various beta-lactamase producers, although they were not as reliable as either cefpodoxime or ceftazidime. These results indicate the utility of an isogenic panel for identification of candidate drugs among many for further testing with clinical isolates of the family Enterobacteriaceae to determine the best agents for detection of specific beta-lactamases in this family.
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Affiliation(s)
- A F Ehrhardt
- Department of Medical Microbiology, Creighton University School of Medicine, Omaha, Nebraska 68178, USA.
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23
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Abstract
BACKGROUND Bacteria can mutate to acquire quinolone resistance by target alterations or diminished drug accumulation. Plasmid-mediated resistance to quinolones in clinical isolates has been claimed but not confirmed. We investigated whether a multiresistance plasmid could transfer resistance to quinolones between bacteria. METHODS We transferred resistance between strains by conjugation. The resistance plasmid was visualised in different hosts by agarose-gel electrophoresis. We determined the frequency of spontaneous mutations to ciprofloxacin or nalidixic-acid resistance in Escherichia coli strains, with or without the quinolone resistance plasmid. FINDINGS A multiresistance plasmid (pMG252) from a clinical isolate of Klebsiella pneumoniae was found to increase quinolone resistance to minimum inhibitory concentrations (MICs) as high as 32 microg/mL for ciprofloxacin when transferred to strains of K pneumoniae deficient in outer-membrane porins. Much lower resistance was seen when pMG252 was introduced into K pneumoniae or E coli strains with normal porins. The plasmid had a wide host range and expressed quinolone resistance in other enterobacteriaceae and in Pseudomonas aeruginosa. From a plasmid-containing E coli strain with ciprofloxacin MIC of 0.25 microg/mL and nalidixic-acid MIC of 32 microg/mL, quinolone-resistant mutants could be obtained at more than 100 times the frequency of a plasmid-free strain, reaching MICs for ciprofloxacin of 4 microg/mL and for nalidixic acid of 256 microg/mL. INTERPRETATION Transferable resistance to fluoroquinines and nalidixic acid has been found in a clinical isolate of K pneumoniae on a broad host range plasmid. Although resistance was low in wild-type strains, higher levels of quinolone resistance arose readily by mutation. Such a plasmid can speed the development and spread of resistance to these valuable antimicrobial agents.
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Affiliation(s)
- L Martínez-Martínez
- Department of Clinical Microbiology, School of Medicine, University of Seville, Spain
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24
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Schumacher H, Skibsted U, Skov R, Scheibel J. Cefuroxime resistance in Escherichia coli. Resistance mechanisms and prevalence. APMIS 1996; 104:531-8. [PMID: 8920806 DOI: 10.1111/j.1699-0463.1996.tb04908.x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
In order to characterize cefuroxime resistance in Escherichia coli 22 clinical isolates were investigated for susceptibility to different beta-lactam antibiotics and ciprofloxacin. The production of beta-lactamases, the pattern of the major outer membrane proteins (OMPs), and the plasmid profiles were determined for these isolates. Ten of the isolates were resistant to ceftazidime, two to cefotaxime, and none was resistant to imipenem or ciprofloxacin. The dominating resistance mechanism was hyperproduction of the chromosomally encoded beta-lactamase to some extent accompanied by alterations of the OMP's. Two isolates with low ampicillin MIOs seemed solely to have alteration of the OMPs. None of the isolates produced plasmid-mediated extended-spectrum beta-lactamases. In addition, the prevalence of cefuroxime resistance was investigated. The prevalence as attained in 8704 clinical isolates of E. coli collected from Copenhagen County during a 5-year period (1990-1994) was 4.4%, but there was considerable variation among specimens from different sites of the body. Isolates from blood were much less resistant (2.5%) than isolates from the respiratory tract (9.7%).
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Affiliation(s)
- H Schumacher
- Department of Clinical Microbiology, Herlev University Hospital, Copenhagen County, Denmark
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25
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Jacoby GA, Han P. Detection of extended-spectrum beta-lactamases in clinical isolates of Klebsiella pneumoniae and Escherichia coli. J Clin Microbiol 1996; 34:908-11. [PMID: 8815106 PMCID: PMC228915 DOI: 10.1128/jcm.34.4.908-911.1996] [Citation(s) in RCA: 229] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
Forty clinical isolates of Escherichia coli and 141 isolates of Klebsiella pneumoniae that either transferred ceftazidime resistance or showed sulbactam enhancement of oxyimino-beta-lactam susceptibility were tested by disk diffusion methodology for susceptibility to aztreonam, cefotaxime, ceftazidime, and cefoxitin. With standard 30 micrograms antibiotic disks, the fraction of these extended-spectrum beta-lactamase (ESBL)-producing isolates testing resistant by National Committee for Clinical Laboratory Standards criteria was lowest (24%) with cefotaxime disks. Forty percent of the E. coli and 29% of the K. pneumoniae isolates appeared susceptible with at least one oxyimino-beta-lactam disk. Ceftazidime and aztreonam disks were equivalent in differentiating ESBL production, and both were superior to cefotaxime disks. Over half the E. Coli and 29% of the K. pneumoniae isolates tested cefoxitin resistant. In 30 isolates, cefoxitin resistance was transmissible and due to a plasmid-mediated AmpC-type beta-lactamase. With a 5-micrograms ceftazidime disk, a breakpoint could be chosen with high sensitivity and specificity for ESBL-producing organisms. Present disk diffusion criteria underestimate the prevalence of ESBL-producing strains.
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Affiliation(s)
- G A Jacoby
- Lahey Hitchcock Clinic, Burlington, Massachusetts 01805, USA
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26
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Ohsuka S, Arakawa Y, Horii T, Ito H, Ohta M. Effect of pH on activities of novel beta-lactamases and beta-lactamase inhibitors against these beta-lactamases. Antimicrob Agents Chemother 1995; 39:1856-8. [PMID: 7486932 PMCID: PMC162839 DOI: 10.1128/aac.39.8.1856] [Citation(s) in RCA: 26] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
Abstract
The effects of acidic conditions on activities of seven beta-lactamases--TEM-1 (class A), KOXY (class A), IMP-1 (class B), AmpC (class C), MOX-1 (class C), OXA-5 (class D), and PSE-2 (class D)--and their inhibitors were measured. The enzymatic activities of KOXY, IMP-1, and MOX-1 at pH 5.8 were slightly lower than those at pH 7.5. However, the activities of PSE-2 and OXA-5 were greatly reduced at pH 5.8. All of the beta-lactamase inhibitors tested had poorer inhibitory activities at pH 5.8 than at pH 7.5 except clavulanic acid for TEM-1.
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Affiliation(s)
- S Ohsuka
- Department of Bacteriology, Nagoya University School of Medicine, Japan
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27
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Scoulica E, Aransay A, Tselentis Y. Molecular characterization of the OXA-7 beta-lactamase gene. Antimicrob Agents Chemother 1995; 39:1379-82. [PMID: 7574536 PMCID: PMC162747 DOI: 10.1128/aac.39.6.1379] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
The OXA-7 gene, which encodes an oxacillinase, was cloned from plasmid pMG202 of Escherichia coli isolate 7181 (A. A. Medeiros, M. Cohenford, and G. A. Jacoby, Antimicrob. Agents Chemother. 27:715-719, 1985) and sequenced. The nucleotide sequence of the OXA-7 gene was closely related to that of the OXA-10 (PSE-2) gene, with a derived amino acid sequence of the OXA-7 enzyme showing greater than 95% homology with those of OXA-10 and OXA-11.
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Affiliation(s)
- E Scoulica
- Department of Bacteriology, Parasitology, Zoonoses and Geographical Medicine, Faculty of Medicine, University of Crete, Heraklion-Crete, Greece
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28
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Bush K, Jacoby GA, Medeiros AA. A functional classification scheme for beta-lactamases and its correlation with molecular structure. Antimicrob Agents Chemother 1995; 39:1211-33. [PMID: 7574506 PMCID: PMC162717 DOI: 10.1128/aac.39.6.1211] [Citation(s) in RCA: 1550] [Impact Index Per Article: 53.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Affiliation(s)
- K Bush
- American Cyanamid Company, Lederle Laboratories, Pearl River, New York 10965, USA
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29
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Bradford PA, Sanders CC. Development of test panel of beta-lactamases expressed in a common Escherichia coli host background for evaluation of new beta-lactam antibiotics. Antimicrob Agents Chemother 1995; 39:308-13. [PMID: 7726487 PMCID: PMC162532 DOI: 10.1128/aac.39.2.308] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
A test panel of 35 different beta-lactamases expressed in a common Escherichia coli host was created to compare the effect that each beta-lactamase had on susceptibility to various beta-lactam antibiotics. A comparison of the MICs obtained with this panel generally reflected differences in the substrate profiles of the various beta-lactamases examined. In addition, several strains of the panel were subjected to selection with porin-specific bacteriophages to obtain mutants lacking either the OmpC or OmpF porin protein. A mutation in either OmpC or OmpF did change the susceptibilities of certain strains expressing beta-lactamase to certain beta-lactam antibiotics. However, the loss of a single porin did not predictably alter susceptibility to any given beta-lactam drug. This panel of strains producing various beta-lactamases was found to be a useful tool for comparing the effects of different beta-lactamases and outer membrane permeability upon susceptibility to beta-lactam drugs.
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Affiliation(s)
- P A Bradford
- Department of Medical Microbiology, Creighton University, Omaha, Nebraska 68178, USA
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30
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Weischer M, Schumacher H, Kolmos HJ. Resistance characteristics of blood culture isolates of Enterobacter cloacae with special reference to beta-lactamases and relation to preceding antimicrobial therapy. APMIS 1994; 102:356-66. [PMID: 8024737 DOI: 10.1111/j.1699-0463.1994.tb04884.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Resistance characteristics of 53 blood culture isolates of E. cloacae were examined and correlated with antimicrobial treatment preceding bacteraemia. Resistance patterns of 22 antimicrobial agents, presence of resistant mutants, and inducibility of beta-lactamase were investigated; furthermore, population analysis and investigation of beta-lactamase production of selected isolates were performed. Thirty-two isolates (60%) were resistant to cephalothin and/or cefoxitin and/or ampicillin, and 14 isolates (26%) had further resistance characteristics, 7 of the 14 being resistant to non-beta-lactam antibiotics. All ampicillin-susceptible and 76% of cefotaxime-susceptible isolates had resistant mutants in the zone of inhibition when high inoculum was used. All isolates investigated had inducible chromosomal beta-lactamases, and, in addition, two isolates had an enzyme corresponding with TEM-1. Correlation of resistance patterns and antimicrobial treatment preceding bacteraemia showed that treatment with a third-generation cephalosporin was associated with beta-lactam multiresistance. In conclusion, susceptibility testing of beta-lactam antibiotics of Enterobacter must be interpreted with caution and monotherapy with an extended-spectrum cephalosporin should be avoided unless presence of resistant mutants and inducibility of beta-lactamase can be excluded.
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Affiliation(s)
- M Weischer
- Department of Clinical Microbiology, Statens Seruminstitut, Copenhagen, Denmark
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31
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Payne DJ, Cramp R, Winstanley DJ, Knowles DJ. Comparative activities of clavulanic acid, sulbactam, and tazobactam against clinically important beta-lactamases. Antimicrob Agents Chemother 1994; 38:767-72. [PMID: 8031044 PMCID: PMC284540 DOI: 10.1128/aac.38.4.767] [Citation(s) in RCA: 112] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
Clavulanic acid, sulbactam, and tazobactam are inhibitors of a variety of plasmid-mediated beta-lactamases. However, inhibition data for these three inhibitors with a wide range of different plasmid-mediated beta-lactamases have not yet been compared under the same experimental conditions. A number of groups have inferred that clavulanic acid inhibits extended-spectrum TEM and SHV beta-lactamases, but inhibition data have rarely been published. In this study, the 50% inhibitory concentrations of these three beta-lactamase inhibitors for 35 plasmid-mediated beta-lactamases have been determined. Of these 35 beta-lactamases, 20 were extended-spectrum TEM- or SHV-derived beta-lactamases. The other 15 enzymes were conventional-spectrum beta-lactamases such as TEM-1 and SHV-1. Clavulanic acid was a more potent inhibitor than sulbactam for 32 of the 35 plasmid-mediated beta-lactamases tested. In particular, clavulanic acid was 60 and 580 times more potent than sulbactam against TEM-1 and SHV-1, respectively, currently the two most clinically prevalent gram-negative plasmid-mediated beta-lactamases. Statistical analysis of the data of the 50% inhibitory concentrations showed that clavulanic acid was 20 times more active overall than sulbactam against the conventional-spectrum enzymes. In addition, clavulanic acid was 14 times more potent than sulbactam at inhibiting the extended-spectrum enzymes. Tazobactam also showed significantly greater activity than sulbactam against the two groups of beta-lactamases. There were no significant differences between the overall activities of tazobactam and clavulanic acid against the extended-spectrum TEM and SHV enzymes and conventional-spectrum enzymes, although differences in their inhibition profiles were observed.
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Affiliation(s)
- D J Payne
- SmithKline Beecham Pharmaceuticals, Betchworth, Surrey, United Kingdom
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32
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Abstract
The hydrolysis time courses of 22 beta-lactam antibiotics by the class D OXA2 beta-lactamase were studied. Among these, only three appeared to correspond to the integrated Henri-Michaelis equation. 'Burst' kinetics, implying branched pathways, were observed with most penicillins, cephalosporins and with flomoxef and imipenem. Kinetic parameters characteristic of the different phases of the hydrolysis were determined for some substrates. Mechanisms generally accepted to explain such reversible partial inactivations involving branches at either the free enzyme or the acyl-enzyme were inadequate to explain the enzyme behaviour. The hydrolysis of imipenem was characterized by the occurrence of two 'bursts', and that of nitrocefin by a partial substrate-induced inactivation complicated by a competitive inhibition by the hydrolysis product.
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Affiliation(s)
- P Ledent
- Laboratoire d'Enzymologie, Université de Liège, Sart-Tilman, Belgium
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33
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Ledent P, Raquet X, Joris B, Van Beeumen J, Frère JM. A comparative study of class-D beta-lactamases. Biochem J 1993; 292 ( Pt 2):555-62. [PMID: 8389139 PMCID: PMC1134246 DOI: 10.1042/bj2920555] [Citation(s) in RCA: 76] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
Three class-D beta-lactamases (OXA2, OXA1 and PSE2) were produced and purified to protein homogeneity. 6 beta-Iodopenicillanate inactivated the OXA2 enzyme without detectable turnover. Labelling of the same beta-lactamase with 6 beta-iodo[3H]penicillanate allowed the identification of Ser-70 as the active-site serine residue. In agreement with previous reports, the apparent M(r) of the OXA2 enzyme as determined by molecular-sieve filtration, was significantly higher than that deduced from the gene sequence, but this was not due to an equilibrium between a monomer and a dimer. The heterogeneity of the OXA2 beta-lactamase on ion-exchange chromatography contrasted with the similarity of the catalytic properties of the various forms. A first overview of the enzymic properties of the three 'oxacillinases' is presented. With the OXA2 enzyme, 'burst' kinetics, implying branched pathways, seemed to prevail with many substrates.
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Affiliation(s)
- P Ledent
- Laboratoire d'Enzymologie, Université de Liège, Belgium
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34
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35
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Couture F, Lachapelle J, Levesque RC. Phylogeny of LCR-1 and OXA-5 with class A and class D beta-lactamases. Mol Microbiol 1992; 6:1693-705. [PMID: 1495394 DOI: 10.1111/j.1365-2958.1992.tb00894.x] [Citation(s) in RCA: 124] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
The nucleotide sequences of blaLCR-1 and blaOXA-5 beta-lactamase genes have been determined. Polypeptide products of 260 and 267 amino acids with estimated molecular masses of 27 120 Da and 27,387 Da were obtained for the mature form of LCR-1 and OXA-5 proteins. A progressive alignment was used to evaluate the extent of identity between LCR-1 and OXA-5 with 29 other beta-lactamase amino acid sequences. The data showed that both belong to class D. We identified amino acids conserved in 24 positions for class A beta-lactamases and in 28 positions for five class D enzymes. The structural similarities between class A and class D beta-lactamases are more extensive than indicated by earlier biochemical studies with overall 16% identity between both classes. From the alignment, dendograms were constructed with a distance-matrix and parsimony methods which defined three major groups of proteins subdivided into clusters giving insight on beta-lactamase phylogeny and evolution.
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Affiliation(s)
- F Couture
- Département de Microbiologie, Faculté de Médécine, Université Laval, Sainte-Foy, Québec, Canada
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36
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Abstract
A disc diffusion method, based on the idea of Klundert, for screening of substrate profiles of beta-lactamases was developed in order to perform epidemiological studies. The method was tested against 30 different reference beta-lactamases and 59 clinical isolates known to produce TEM-1, SHV-1 and BRO-1. The reproducibility and discriminating power of the disc diffusion method made it possible to differentiate between eight types of substrate profiles for the 30 reference beta-lactamases and to differentiate between TEM-1, SHV-1 and BRO-1 from clinical isolates. In combination with analytical isoelectric focusing the disc diffusion method gives a reliable identification of beta-lactamases.
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Affiliation(s)
- H Schumacher
- Department of Hospital Infections and Antibiotics, Immunological R & D, Copenhagen, Denmark
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37
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Papanicolaou GA, Medeiros AA, Jacoby GA. Novel plasmid-mediated beta-lactamase (MIR-1) conferring resistance to oxyimino- and alpha-methoxy beta-lactams in clinical isolates of Klebsiella pneumoniae. Antimicrob Agents Chemother 1990; 34:2200-9. [PMID: 1963529 PMCID: PMC172023 DOI: 10.1128/aac.34.11.2200] [Citation(s) in RCA: 193] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
Klebsiella pneumoniae isolates from 11 patients at the Miriam Hospital were identified as resistant to cefoxitin and ceftibuten as well as to aztreonam, cefotaxime, and ceftazidime. Resistance could be transferred by conjugation or transformation with plasmid DNA into Escherichia coli and was due to the production of a beta-lactamase with an isoelectric point of 8.4 named MIR-1. In E. coli, MIR-1 conferred resistance to aztreonam, cefotaxime, ceftazidime, ceftibuten, ceftriaxone, and such alpha-methoxy beta-lactams as cefmetazole, cefotetan, cefoxitin, and moxalactam. In vitro, MIR-1 hydrolyzed cephalothin and cephaloridine much more rapidly than it did penicillin G, ampicillin, or carbenicillin. Cefotaxime was hydrolyzed at 10% the rate of cephaloridine. Cefoxitin inactivation could only be detected by a microbiological test. The inhibition profile of MIR-1 was similar to that of chromosomally mediated class I beta-lactamases. Potassium clavulanate had little effect on cefoxitin or cefibuten resistance and was a poor inhibitor of MIR-1 activity. Cefoxitin or imipenem did not induce MIR-1. The gene determining MIR-1 was cloned on a 1.4-kb AccI-PstI fragment. Under stringent conditions, probes for TEM-1 and SHV-1 genes and the E. coli ampC gene failed to hybridize with the MIR-1 gene. However, a provisional sequence of 150 bp of the MIR-1 gene proved to be 90% identical to the sequence of ampC from Enterobacter cloacae but only 71% identical to that of E. coli, thus explaining the lack of hybridization to the E. coli ampC probe. Plasmid profiles of the 11 K. pneumoniae clinical isolates were not identical, but each contained a plasmid from 40 to 60 kb that hybridized with the cloned MIR-1 gene. Both transfer-proficient and transfer-deficient MIR-1 plasmids belonged to the N incompatibility group. Thus, the resistance of these K. pneumoniae strains was the result of plasmid acquisition of a class I beta-lactamase, a new resistance determinant that expands the kinds of beta-lactam resistance capable of spread by plasmid dissemination among clinical isolates.
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Affiliation(s)
- G A Papanicolaou
- Division of Infectious Diseases, Miriam Hospital, Providence, Rhode Island 02906
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Papanicolaou GA, Medeiros AA. Discrimination of extended-spectrum beta-lactamases by a novel nitrocefin competition assay. Antimicrob Agents Chemother 1990; 34:2184-92. [PMID: 2073109 PMCID: PMC172021 DOI: 10.1128/aac.34.11.2184] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
We describe a nitrocefin competition assay for determining inhibition profiles as a useful adjunct to existing biochemical methods for the discrimination of beta-lactamases. The hydrolysis rate of nitrocefin was measured with a plate photometer as the change in A480 over 45 min in the presence of 17 inhibitors. Fourteen well-established beta-lactamases and 13 extended-spectrum beta-lactamases were tested. Correlations with data from isoelectric focusing and amino acid sequencing suggested that the inhibition profile reflects alterations in the active-site configuration of beta-lactamases. The method was especially useful in measuring the relative affinities of beta-lactamases against poorly hydrolyzed substrates and in screening large numbers of isolates for the detection of new beta-lactamase types.
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Affiliation(s)
- G A Papanicolaou
- Division of Infectious Diseases and Clinical Microbiology, Miriam Hospital, Providence, Rhode Island
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39
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Shlaes DM, Currie-McCumber C, Hull A, Behlau I, Kron M. OHIO-1 beta-lactamase is part of the SHV-1 family. Antimicrob Agents Chemother 1990; 34:1570-6. [PMID: 2121093 PMCID: PMC171875 DOI: 10.1128/aac.34.8.1570] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
The OHIO-1 beta-lactamase gene was subcloned in a 1.16-kilobase TaqI fragment in the 2.4-kilobase chimeric plasmid pSK04. After directional subcloning into M13, the DNA sequence of this fragment was determined. The results showed an open reading frame of 858 base pairs (bp) encoding a protein of 286 amino acids. The structural gene showed 95, 87, and 60% DNA sequence identity with SHV-1, LEN-1, and TEM-1, respectively, and 93, 85, and 62% predicted amino acid sequence identity, respectively. The 87 bp upstream of the OHIO-1 structural gene had 96% identity with the upstream flanking sequence of SHV-1, including the -35 and -10 consensus sequences and the putative ribosomal binding site. A 223-bp DNA probe derived from a PstI-HaeII fragment in the C-terminal sequence of OHIO-1 had predicted 96, 88, and 61% sequence identity with SHV-1, LEN-1, and TEM-1, respectively. This probe hybridized to SHV-1 and poorly to LEN-1, but not to TEM-1 or a variety of other plasmid-mediated beta-lactamase genes, under stringent conditions. Screening of plasmid DNA derived from 40 ampicillin-resistant clinical isolates by Southern hybridization with the 223-bp probe uncovered no strains encoding OHIO-1. Isoelectric focusing of the same collection did identify two strains producing enzymes resembling SHV-1, however. We have also performed a kinetic comparison of OHIO-1, SHV-1, and TEM-1. OHIO-1 and SHV-1 were indistinguishable from each other but could be distinguished from TEM-1. These data clearly place OHIO-1 within the SHV-1 family of beta-lactamases.
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Affiliation(s)
- D M Shlaes
- Infectious Diseases Section, Veterans Administration Medical Center, Cleveland, Ohio
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40
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Lafond M, Couture F, Vézina G, Levesque RC. Evolutionary perspectives on multiresistance beta-lactamase transposons. J Bacteriol 1989; 171:6423-9. [PMID: 2556363 PMCID: PMC210530 DOI: 10.1128/jb.171.12.6423-6429.1989] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
A series of intragenic DNA probes, encoding the major part of the transposase resolvase and inverted repeats of transposons Tn3, Tn21, and Tn2501, were used in hybridization assays for homologous DNA sequences in 18 transposons studied. The tnpA and tnpR probes detected extensive homology with Tn3-like and Tn21-like elements for 11 transposons. This high degree of homology was confirmed with the 38- and 48-base-pair inverted-repeat oligonucleotide probes of Tn3, Tn21, and Tn2501. The Southern-type gel hybridization experiments localized the tnpA-homologous sequences on the physical DNA maps constructed. The genetic and physical maps of the transposons were compared, as were their nucleic acid sequence homologies. These comparisons suggested a subfamily of mobile elements distinct from but related to the Tn21 group. Based on these results, an evolutionary model is proposed and a pedigree is presented for the genesis of multiresistance beta-lactamase transposons.
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Affiliation(s)
- M Lafond
- Département de Microbiologie, Faculté de Médecine, Université Laval, Quebec, Canada
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41
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Sentochnik DE, Eliopoulos GM, Ferraro MJ, Moellering RC. Comparative in vitro activity of SM7338, a new carbapenem antimicrobial agent. Antimicrob Agents Chemother 1989; 33:1232-6. [PMID: 2508543 PMCID: PMC172631 DOI: 10.1128/aac.33.8.1232] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
The comparative in vitro activity of SM7338 was tested against 670 routine clinical isolates and 130 cefoperazone-resistant isolates of bacteria by agar dilution methods. SM7338 was at least as active as imipenem against gram-negative organisms but was slightly less active against gram-positive organisms. SM7338 was particularly active against members of the family Enterobacteriaceae, with MICs for 90% of strains of less than or equal to 0.125 micrograms/ml for all species tested. Differences in activity between SM7338 and imipenem were particularly striking against Proteus vulgaris, Proteus mirabilis, and Morganella morganii, against which MICs of SM7338 and imipenem for 90% of strains were 0.125 and 4 micrograms/ml, respectively. The presence of unique plasmid-mediated beta-lactamases in Pseudomonas aeruginosa PU21 transconjugants did not affect activity substantially, except in the case of OXA-2 (eightfold-increased MIC) and OXA-3 (fourfold-increased MIC). SM7338 was also active against a laboratory-derived strain of P. aeruginosa which hyperproduced chromosomal beta-lactamase, inhibiting both the wild type and the mutant at a concentration of 1.0 micrograms/ml.
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Affiliation(s)
- D E Sentochnik
- Department of Medicine, New England Deaconess Hospital, Boston, Massachusetts 02215
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Boissinot M, Huot A, Mercier J, Levesque RC. Development of gene probes and evolutionary relationships of the PSE-4 bla gene to plasmid-mediated beta-lactamases of gram-negative bacteria. Mol Cell Probes 1989; 3:179-88. [PMID: 2788807 DOI: 10.1016/0890-8508(89)90028-5] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Six types of plasmid-mediated carbenicillinases can be distinguished on the basis of their substrate profiles, molecular mass isoelectric values and immunological properties. As yet, no structural classification has been attempted for these enzymes at the molecular level. We have isolated the PSE-4 structural gene responsible for carbenicillinase production in Pseudomonas aeruginosa strain Dalgleish and studied its expression in E. coli. A detailed physical map of the cloned fragment and the construction of deletion mutants permitted the precise localization of the PSE-4 structural gene. Various restriction endonuclease fragments known to be flanking or internal to the PSE-4 bla gene were used as DNA probes and tested for homologous sequences in other beta-lactamase genes. A collection of three restriction fragment probes internal or delimiting the PSE-4 structural gene were hybridized with purified plasmid DNA coding for 18 other beta-lactamases. Under high stringency conditions, only the PSE-1, CARB-3 and CARB-4 genes cross-hybridized with PSE-4; while one of the probes tested hybridized solely with CARB-3. Further analysis indicated that the PSE-1, PSE-4, CARB-3 and CARB-4 bla genes are related and could presumably have evolved from a common progenitor.
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Affiliation(s)
- M Boissinot
- Département de Microbiologie et d'Immunologie, Faculté de Médecine, Université Laval, Québec, Canada
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Proprietes des nouvelles beta-lactamases plasmidiques actives sur les cephalosporines de troisieme generation. position dans la classe a des beta-lactamases. Med Mal Infect 1989. [DOI: 10.1016/s0399-077x(89)80159-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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45
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Bush K. Classification of beta-lactamases: groups 2c, 2d, 2e, 3, and 4. Antimicrob Agents Chemother 1989; 33:271-6. [PMID: 2658781 PMCID: PMC171478 DOI: 10.1128/aac.33.3.271] [Citation(s) in RCA: 128] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Affiliation(s)
- K Bush
- Squibb Institute for Medical Research, Princeton, New Jersey 08540
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46
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Bush K. Classification of beta-lactamases: groups 1, 2a, 2b, and 2b'. Antimicrob Agents Chemother 1989; 33:264-70. [PMID: 2658780 PMCID: PMC171477 DOI: 10.1128/aac.33.3.264] [Citation(s) in RCA: 164] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Affiliation(s)
- K Bush
- Squibb Institute for Medical Research, Princeton, New Jersey 08540
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47
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Shaokat S, Sirot D, M'Boup S, Petat E, Rich C, Joly B, Denis F, Cluzel R. Resistance aux antibiotiques et distribution particuliere des beta-lactamases plasmidiques chez les colibacilles isoles de diarrhees infantiles aigues en Afrique. Med Mal Infect 1988. [DOI: 10.1016/s0399-077x(88)80198-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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48
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Labia R. β-Lactamases inductibles et constitutives. Med Mal Infect 1988. [DOI: 10.1016/s0399-077x(88)80339-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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49
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Gilbert MP, Summers AO. The distribution and divergence of DNA sequences related to the Tn21 and Tn501 mer operons. Plasmid 1988; 20:127-36. [PMID: 2853392 DOI: 10.1016/0147-619x(88)90015-7] [Citation(s) in RCA: 28] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
The mercury resistance (mer) operons of the Gram-negative bacterial transposons, Tn21 and Tn501, are phenotypically indistinguishable and have extensive DNA identity. However, Tn21 mer has an additional coding region (merC) in the middle of the operon which is lacking in Tn501 and there is also a discrete region of the mercuric ion reductase gene (merA) which differs markedly between the two operons. DNA fragment probes were used to determine the distribution of specific mer coding regions in two distinct collections of mercury-resistant (Hgr) Gram-negative bacteria. Colony blot hybridization analysis showed that merC-positive operons occur almost exclusively in Escherichia, although merC-negative operons can also be found in this genus. The merC-negative operons were found in Citrobacter, Klebsiella, and Enterobacter and in some Pseudomonas. Most of the Pseudomonas did not hybridize detectably with either of the two operons studied, indicating that they harbor an unrelated or more distantly related class of mercury resistance locus. Southern hybridization patterns demonstrated that the merC-positive mer operon is well conserved at the DNA level, whereas the merC-negative operons are much less conserved. The presence of merC also correlated with conservation of a specific variant region of the merA gene and with an antibiotic resistance pattern similar to that of Tn21. Tn501 appears to be an atypical example of the merC-negative subgroup of Hgr loci.
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Affiliation(s)
- M P Gilbert
- Department of Microbiology, University of Georgia, Athens 30602
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50
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Matsumoto Y, Ikeda F, Kamimura T, Yokota Y, Mine Y. Novel plasmid-mediated beta-lactamase from Escherichia coli that inactivates oxyimino-cephalosporins. Antimicrob Agents Chemother 1988; 32:1243-6. [PMID: 3056257 PMCID: PMC172385 DOI: 10.1128/aac.32.8.1243] [Citation(s) in RCA: 101] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
A highly cephem-resistant Escherichia coli strain, FP1546, isolated from the fecal flora of laboratory dogs previously administered beta-lactam antibiotics was found to produce a beta-lactamase, FEC-1, of 48-kilodalton size and pI 8.2. FEC-1 hydrolyzed cefuroxime, cefotaxime, cefmenoxime, and ceftriaxone, as well as the enzymatically less-stable antibiotics cephaloridine, cefotiam, and cefpiramide. Of the oxyimino-cephalosporins, ceftizoxime was fairly stable to FEC-1. FEC-1 differed notably from chromosomal E. coli cephalosporinase, especially in its broad-spectrum substrate profile and its high inhibition by clavulanic acid, sulbactam, and imipenem. A conjugation study revealed that FEC-1 was encoded by a 74-megadalton plasmid, pFCX1. This may be the first instance of a plasmid-mediated oxyimino-cephalosporinase from E. coli.
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Affiliation(s)
- Y Matsumoto
- Research Laboratories, Fujisawa Pharmaceutical Co., Ltd., Osaka, Japan
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