title: Characterization of sterol glucosyltransferase from Salinispora tropica CNB-440: potential enzyme for the biosynthesis of sitosteryl glucoside.
abstract: A sterol glucosyltransferase-encoded gene was isolated from Salinispora tropica CNB-440, a marine, sediment-dwelling, Gram positive bacterium that produces the potent anticancer compound, salinosporamide A. The full-length gene consists of 1284 nucleotides and encodes 427 amino acids with a calculated mass of 45.65kDa. The gene was then cloned and heterologously expressed in Escherichia coli BL21(DE3). The amino acid sequence shares 39% similarity with the glycosyltransferase from Withania somnifera, which belongs to glycosyltransferase family 1. Enzyme reactions were carried out with the various free sterols (acceptor) and NDP-sugars (donor). The purified protein only showed activity for glucosylation of β-sitosterol with UDP-D-glucose and TDP-D-glucose donors, and optimal activity at pH 7.5 and 37°C. Among these two donors, UDP-D-glucose was preferred.
authors.affiliation: Department of Pharmaceutical Engineering, Institute of Biomolecule Reconstruction, SunMoonUniversity, #100, Kalsan-ri, Tangjeong-myeon, Asan-si, Chungnam 336-708, Republic of Korea.
authors.forename: Nguyen Huy
authors.initials: NH
authors.lastname: Thuan
authors.forename: Tokutaro
authors.initials: T
authors.lastname: Yamaguchi
authors.forename: Joo Ho
authors.initials: JH
authors.lastname: Lee
authors.forename: Jae Kyung
authors.initials: JK
authors.lastname: Sohng
mesh_terms: D000595:Amino Acid Sequence; D001426:Bacterial Proteins / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism*; D005798:Genes, Bacterial; D005960:Glucosides / Q000096:biosynthesis*; D005964:Glucosyltransferases / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism*; D007700:Kinetics; D008848:Micromonosporaceae / Q000201:enzymology* / Q000235:genetics; D008969:Molecular Sequence Data; D010802:Phylogeny; D017386:Sequence Homology, Amino Acid; D012855:Sitosterols / Q000378:metabolism*; D013379:Substrate Specificity
chemical_list: D001426:Bacterial Proteins; D005960:Glucosides; D012855:Sitosterols; D005964:Glucosyltransferases; C085360:sterol 3-beta-glucosyltransferase