title: Deletion mutations conferring substrate spectrum extension in the class A β-lactamase.
abstract: 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 conferring high-level ceftazidime resistance on isolates from clinical settings, compared with amino acid substitution mutations.
authors: Department of Medicine, Korea University, Anam-Dong, Seongbuk-Gu, Seoul, South Korea.
authors: Junghyun
authors: J
authors: Hwang
authors: School of Systems Biomedical Science and Research Center for Integrative Basic Science, Soongsil University, Seoul, South Korea.
authors: Kwang-Hwi
authors: KH
authors: Cho
authors: Department of Medicine, Korea University, Anam-Dong, Seongbuk-Gu, Seoul, South Korea.
authors: Han
authors: H
authors: Song
authors: Department of Medicine, Korea University, Anam-Dong, Seongbuk-Gu, Seoul, South Korea.
authors: Hyojeong
authors: H
authors: Yi
authors: Department of Medicine, Korea University, Anam-Dong, Seongbuk-Gu, Seoul, South Korea Department of Biosystems and Biotechnology, Korea University, Anam-Dong, Seongbuk-Gu, Seoul, South Korea hstanleykim@korea.ac.kr.
authors: Heenam Stanley
authors: HS
authors: Kim
mesh_terms: D019117:Burkholderia / Q000201:enzymology* / Q000235:genetics*; D017384:Sequence Deletion / Q000235:genetics*; D001618:beta-Lactamases / Q000235:genetics*
chemical_list: D001618:beta-Lactamases