TEM-89 β-Lactamase Produced by a Proteus mirabilis Clinical Isolate: New Complex Mutant (CMT 3) with Mutations in both TEM-59 (IRT-17) and TEM-3

ABSTRACT TEM-89 (CMT-3) is the first complex mutant β-lactamase produced by a clinical strain of Proteus mirabilis (strain Pm 631). This new enzyme, which has a pI of 6.28, is derived from TEM-3 and has a single amino acid substitution also encountered in TEM-59 (inhibitor-resistant TEM β-lactamase IRT-17): Ser-130 to Gly. TEM-89 hydrolyzed penicillins to the same extent that TEM-3 did but lost almost all hydrolytic activity for cephalosporins and, like TEM-59, was highly resistant to inhibitors.

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A single amino acid substitution in PmrB is associated with polymyxin B resistance in clinical isolate ofPseudomonas aeruginosa

FEMS Microbiology Letters ◽

10.1111/j.1574-6968.2009.01720.x ◽

2009 ◽

Vol 298 (2) ◽

pp. 249-254 ◽

Cited By ~ 31

Author(s):

Neethu Abraham ◽

Dong H. Kwon

Keyword(s):

Amino Acid ◽

Clinical Isolate ◽

Amino Acid Substitution ◽

Polymyxin B ◽

Single Amino Acid Substitution ◽

Single Amino Acid

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NDM-4 Metallo-β-Lactamase with Increased Carbapenemase Activity from Escherichia coli

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.05961-11 ◽

2012 ◽

Vol 56 (4) ◽

pp. 2184-2186 ◽

Cited By ~ 87

Author(s):

Patrice Nordmann ◽

Anne E. Boulanger ◽

Laurent Poirel

Keyword(s):

Escherichia Coli ◽

Amino Acid ◽

Amino Acid Substitution ◽

Active Sites ◽

Hydrolytic Activity ◽

Single Amino Acid Substitution ◽

Single Amino Acid ◽

Amino Acid Substitutions ◽

Content Type

ABSTRACTA clinicalEscherichia coliisolate resistant to all β-lactams, including carbapenems, expressed a novel metallo-β-lactamase (MBL), NDM-4, differing from NDM-1 by a single amino acid substitution (Met154Leu). NDM-4 possessed increased hydrolytic activity toward carbapenems and several cephalosporins compared to that of NDM-1. This amino acid substitution was not located in the known active sites of NDM-1, indicating that remote amino acid substitutions might also play a role in the extended activity of this MBL.

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Capnocytophaga ochracea: Characterization of a Plasmid-Encoded Extended-Spectrum TEM-17 β-Lactamase in the Phylum Flavobacter-Bacteroides

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.44.3.760-762.2000 ◽

2000 ◽

Vol 44 (3) ◽

pp. 760-762 ◽

Cited By ~ 21

Author(s):

Agnes Rosenau ◽

Blandine Cattier ◽

Nathalie Gousset ◽

Patrick Harriau ◽

Alain Philippon ◽

...

Keyword(s):

Amino Acid ◽

Clinical Isolate ◽

Amino Acid Substitution ◽

Single Amino Acid Substitution ◽

Single Amino Acid ◽

Extended Spectrum

ABSTRACT A plasmid-encoded extended-spectrum TEM β-lactamase with a pI of 5.5 was detected in a Capnocytophaga ochracea clinical isolate. The bla gene was associated with a strong TEM-2 promoter and was derived from bla TEM-1a with a single-amino-acid substitution: Glu104→Lys, previously assigned to TEM-17, which is thus the first TEM β-lactamase to be reported in the phylum Flavobacter-Bacteroides.

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A New SHV-Derived Extended-Spectrum β-Lactamase (SHV-24) That Hydrolyzes Ceftazidime through a Single-Amino-Acid Substitution (D179G) in the Ω-Loop

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.44.6.1725-1727.2000 ◽

2000 ◽

Vol 44 (6) ◽

pp. 1725-1727 ◽

Cited By ~ 20

Author(s):

Hiroshi Kurokawa ◽

Tetsuya Yagi ◽

Naohiro Shibata ◽

Keigo Shibayama ◽

Kazunari Kamachi ◽

...

Keyword(s):

Escherichia Coli ◽

Amino Acid ◽

Clinical Isolate ◽

Amino Acid Substitution ◽

Single Amino Acid Substitution ◽

Single Amino Acid ◽

Extended Spectrum ◽

High Level ◽

Level Resistance

ABSTRACT A new SHV-derived extended-spectrum β-lactamase (SHV-24) conferring high-level resistance to ceftazidime but not cefotaxime and cefazolin was identified in Japan. This enzyme was encoded by a transferable 150-kb plasmid from an Escherichia coliclinical isolate. The pI and Km for CAZ of this enzyme were 7.5 and 30 μM, respectively. SHV-24 was found to have a D179G substitution in the Ω-loop of the enzyme.

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