title: Purification and characterization of a novel cis-epoxysuccinate hydrolase from Klebsiella sp. that produces L(+)-tartaric acid.
abstract: A strain of Klebsiella sp. BK-58 that produces cis-epoxysuccinate was screened and identified. This novel enzyme hydrolyzes cis-epoxysuccinate to L(+)-tartaric acid and was purified to homogeneity. Its molecular mass was 30.1 kDa determined by MALDI-TOF-MS analysis. It was stable up to 50 °C and from pH 5 to 11 with optima at 50 °C and pH 8.5. The enzyme was metal-independent and was strongly inhibited by 1 mM Cu(2+) and Ag(+), and 1 % (w/v) SDS. The K m , V max and turnover number (k cat ) values for cis-epoxysuccinate were 19.3, 2.24 mM min(-1) and 220 s(-1), respectively.
authors.affiliation: College of Life Science, Institute of Biochemistry, Zhejiang University, Hangzhou, 310058, Zhejiang, People's Republic of China.
authors.forename: Yongqing
authors.initials: Y
authors.lastname: Cheng
authors.forename: Li
authors.initials: L
authors.lastname: Wang
authors.forename: Haifeng
authors.initials: H
authors.lastname: Pan
authors.forename: Wenna
authors.initials: W
authors.lastname: Bao
authors.forename: Weirong
authors.initials: W
authors.lastname: Sun
authors.forename: Zhipeng
authors.initials: Z
authors.lastname: Xie
authors.forename: Jianguo
authors.initials: J
authors.lastname: Zhang
authors.forename: Yuhua
authors.initials: Y
authors.lastname: Zhao
mesh_terms: D001426:Bacterial Proteins / Q000737:chemistry / Q000302:isolation & purification* / Q000378:metabolism; D004795:Enzyme Stability; D006863:Hydrogen-Ion Concentration; D006867:Hydrolases / Q000737:chemistry / Q000302:isolation & purification* / Q000378:metabolism; D007709:Klebsiella / Q000201:enzymology*; D008670:Metals; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; D013644:Tartrates / Q000378:metabolism*; D013696:Temperature
chemical_list: D001426:Bacterial Proteins; D008670:Metals; D013644:Tartrates; D006867:Hydrolases; C029768:tartaric acid