title: Characterization of a novel metallo-β-lactamases fold hydrolase from Pelagibacterium halotolerans, a marine halotolerant bacterium isolated from East China Sea.
abstract: In this study, a novel metallo-β-lactamases fold hydrolase PH-1 was identified from Pelagibacterium halotolerans B2(T). This novel member of the family Hyphomicrobiaceae was isolated from the East China Sea. In silico analysis demonstrated that PH-1 and its relative homologues cluster in a unique branch and constitute a new subgroup among MBLs. PH-1 was cloned and overexpressed in Escherichia coli BL21 in a soluble form. SDS-PAGE, MALDI-TOF/TOF-MS, and size-exclusion chromatography analysis demonstrated that the PH-1 was a monomer with molecular weight of about 29 kDa. Substrate specificity study showed PH-1 preferred penicillin type β-lactams and exhibited maximum activity toward penicillin-G. Additionally, our experiments also revealed that PH-1 was a halotolerant enzyme since it is active under 4 M NaCl. The enzyme activity of PH-1 was negatively affected by 1 mM Mn(2+) and EDTA. These observations lay a foundation for further study of MBLs from marine bacterium.
authors.affiliation: State Key Laboratory for Diagnosis and Treatment of Infectious Disease, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, The First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, China.
authors.forename: Beiwen
authors.initials: B
authors.lastname: Zheng
authors.affiliation: State Key Laboratory for Diagnosis and Treatment of Infectious Disease, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, The First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, China.
authors.forename: Xiawei
authors.initials: X
authors.lastname: Jiang
authors.affiliation: Ningbo Institute of Microcirculation and Henbane, Ningbo, China.
authors.forename: Zemin
authors.initials: Z
authors.lastname: Xu
authors.affiliation: State Key Laboratory for Diagnosis and Treatment of Infectious Disease, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, The First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, China.
authors.forename: Yunhui
authors.initials: Y
authors.lastname: Fang
authors.affiliation: State Key Laboratory for Diagnosis and Treatment of Infectious Disease, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, The First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, China. ljli@zju.edu.cn.
authors.forename: Lanjuan
authors.initials: L
authors.lastname: Li
mesh_terms: D000595:Amino Acid Sequence; D001426:Bacterial Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D041921:Hyphomicrobiaceae / Q000201:enzymology* / Q000235:genetics / Q000302:isolation & purification; D007769:Lactams / Q000378:metabolism; D008969:Molecular Sequence Data; D013379:Substrate Specificity; D001618:beta-Lactamases / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*
chemical_list: D001426:Bacterial Proteins; D007769:Lactams; D001618:beta-Lactamases
keywords: Halotolerant; Metallo-β-lactamase; Pelagibacterium halotolerans; Purification