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Deletion mutations conferring substrate spectrum extension in the class A ?-lactamase.

ABSTRACT: We describe four new deletion mutations in a class A ?-lactamase PenA in Burkholderia thailandensis, each conferring an extended substrate spectrum. Single-amino-acid deletions T171del, I173del, and P174del and a two-amino-acid deletion, R165_T167delinsP, occurred in the omega loop, increasing the flexibility of the binding cavity. This rare collection of mutations has significance, allowing exploration of the diverse evolutionary trajectories of ?-lactamases and as potential future mutations conferring high-level ceftazidime resistance on isolates from clinical settings, compared with amino acid substitution mutations.

SUBMITTER: Hwang J

PROVIDER: S-EPMC4187959 | biostudies-literature | 2014 Oct

REPOSITORIES: biostudies-literature

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Deletion mutations conferring substrate spectrum extension in the class A β-lactamase.

Hwang Junghyun J Cho Kwang-Hwi KH Song Han H Yi Hyojeong H Kim Heenam Stanley HS

Antimicrobial agents and chemotherapy 20140721 10

We describe four new deletion mutations in a class A β-lactamase PenA in Burkholderia thailandensis, each conferring an extended substrate spectrum. Single-amino-acid deletions T171del, I173del, and P174del and a two-amino-acid deletion, R165_T167delinsP, occurred in the omega loop, increasing the flexibility of the binding cavity. This rare collection of mutations has significance, allowing exploration of the diverse evolutionary trajectories of β-lactamases and as potential future mutations co ...[more]

PMID: 25049254

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