title: Cloning, expression and characterization of meso-2,3-butanediol dehydrogenase from Klebsiella pneumoniae.
abstract: The budC gene encoding the meso-2,3-BDH from Klebsiella pneumoniae XJ-Li was expressed in E. coli BL21 (DE3) pLys. Hypothetical amino acid sequence alignments revealed that the enzyme belongs to the short chain dehydrogenase/reductase family. After purification and refolding, the recombinant enzyme had activities of 218 U/mg for reduction of acetoin and 66 U/mg for oxidation of meso-2,3-butanediol. Highest activities were at pH 8.0 and 9.0 respectively. These are higher than other meso-2,3-butanediol dehydrogenases from K. pneumoniae. The low K (m) value (0.65 mM) for acetoin indicated that the enzyme can easily reduce acetoin to meso-2,3-butanediol. There were no significant activities towards 2R,3R-2,3-butanediol, 1,4-butanediol and 2S,3S-2,3-butanediol, suggesting that the enzyme has a high stereospecificity for the meso-dihydric alcohol.
authors.affiliation: School of Life Science, Beijing Institute of Technology, Beijing, 100081, China. zhgl_food@sina.com
authors.forename: Gen Lin
authors.initials: GL
authors.lastname: Zhang
authors.forename: Cui Wei
authors.initials: CW
authors.lastname: Wang
authors.forename: Chun
authors.initials: C
authors.lastname: Li
mesh_terms: D000429:Alcohol Oxidoreductases / Q000096:biosynthesis* / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D001426:Bacterial Proteins / Q000096:biosynthesis* / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D002072:Butylene Glycols / Q000737:chemistry / Q000378:metabolism; D003001:Cloning, Molecular; D004591:Electrophoresis, Polyacrylamide Gel; D004926:Escherichia coli / Q000201:enzymology / Q000235:genetics; D006863:Hydrogen-Ion Concentration; D007711:Klebsiella pneumoniae / Q000201:enzymology* / Q000235:genetics; D010084:Oxidation-Reduction; D011994:Recombinant Proteins / Q000096:biosynthesis / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D013379:Substrate Specificity; D013696:Temperature
chemical_list: D001426:Bacterial Proteins; D002072:Butylene Glycols; D011994:Recombinant Proteins; C026978:2,3-butylene glycol; D000429:Alcohol Oxidoreductases; C019801:butanediol dehydrogenase