title: Cloning, expression and characterization of the Ste6 gene encoding a UDP-glucose dehydrogenase in Streptomyces.
abstract: Streptomyces sp. 139 was identified to produce a new exopolysaccharide Ebosin (139A) with antirheumatic arthritis activity in vivo. The Ebosin biosynthesis gene cluster(31.3 kb; GenBank Accession Number: AY131229) containing 22 ORFs (ste1-ste22) of Streptomyces sp. 139 had been reported previously. In this paper,we present experimental evidence for the identity of the ste6 gene product as a UDP-glucose dehydrogenase (UDPGDH). With pET-30a as vector,the gene was cloned and expressed in Escherichia coli BL21 (DE3). The expressed protein was purified to homogeneity by His-Bind resin affinity chromatograpy and it was able to catalyze UDP-glucose to UDP-glucuronic acid. To evaluate the function of ste6, the gene was disrupted by a single-crossover homologous recombination event and the result showed that ste6 is required in Ebosin biosynthesis.
authors.affiliation: Institute of Medicinal Biotechnology, Chinese Academy of Medical Sciences, Beijing 100050, China.
authors.forename: Hao
authors.initials: H
authors.lastname: Li
authors.forename: Ling-Yan
authors.initials: LY
authors.lastname: Wang
authors.forename: Gui-Yun
authors.initials: GY
authors.lastname: Xu
authors.forename: Yang
authors.initials: Y
authors.lastname: Chen
authors.forename: Rong
authors.initials: R
authors.lastname: Jiang
authors.forename: Yuan
authors.initials: Y
authors.lastname: Li
mesh_terms: D000595:Amino Acid Sequence; D001483:Base Sequence; D003001:Cloning, Molecular; D015870:Gene Expression; D008969:Molecular Sequence Data; D013302:Streptomyces / Q000201:enzymology* / Q000235:genetics; D014533:Uridine Diphosphate Glucose Dehydrogenase / Q000235:genetics*
chemical_list: D014533:Uridine Diphosphate Glucose Dehydrogenase