title: Improved expression of His(6)-tagged strictosidine synthase cDNA for chemo-enzymatic alkaloid diversification.
abstract: Strictosidine synthase (STR1) catalyzes the stereoselective formation of 3alpha(S)-strictosidine from tryptamine and secologanin. Strictosidine is the key intermediate in the biosynthesis of 2,000 plant monoterpenoid indole alkaloids, and it is a key precursor of enzyme-mediated synthesis of alkaloids. An improved expression system is described which leads to optimized His(6)-STR1 synthesis in Escherichia coli. Optimal production of STR1 was achieved by determining the impact of co-expression of chaperones pG-Tf2 and pG-LJE8. The amount and activity of STR1 was doubled in the presence of chaperone pG-Tf2 alone. His(6)-STR1 immobilized on Ni-NTA can be used for enzymatic synthesis of strictosidines on a preparative scale. With the newly co-expressed His(6)-STR1, novel 3alpha(S)-12-azastrictosidine was obtained by enzymatic catalysis of 7-azatryptamine and secologanin. The results obtained are of significant importance for application to chemo-enzymatic approaches leading to diversification of alkaloids with novel improved structures.
authors.affiliation: Institute of Materia Medica, College of Pharmaceutical Sciences, Zhejiang University, 388 Yu Hang Tang Road, Hangzhou 310058, P. R. China.
authors.forename: Liuqing
authors.initials: L
authors.lastname: Yang
authors.forename: Hongbin
authors.initials: H
authors.lastname: Zou
authors.forename: Huajian
authors.initials: H
authors.lastname: Zhu
authors.forename: Martin
authors.initials: M
authors.lastname: Ruppert
authors.forename: Jingxu
authors.initials: J
authors.lastname: Gong
authors.forename: Joachim
authors.initials: J
authors.lastname: Stöckigt
mesh_terms: D000470:Alkaloids / Q000737:chemistry*; D055162:Biocatalysis; D019759:Carbon-Nitrogen Lyases / Q000235:genetics* / Q000302:isolation & purification / Q000378:metabolism*; D030008:Catharanthus / Q000201:enzymology; D006639:Histidine / Q000235:genetics; D057888:Iridoid Glucosides; D039823:Iridoids / Q000737:chemistry; D018832:Molecular Chaperones / Q000235:genetics / Q000378:metabolism; D009842:Oligopeptides / Q000235:genetics; D011993:Recombinant Fusion Proteins / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism; D014363:Tryptamines / Q000737:chemistry; D014748:Vinca Alkaloids / Q000096:biosynthesis / Q000737:chemistry
chemical_list: D000470:Alkaloids; C471213:His-His-His-His-His-His; D057888:Iridoid Glucosides; D039823:Iridoids; D018832:Molecular Chaperones; D009842:Oligopeptides; D011993:Recombinant Fusion Proteins; D014363:Tryptamines; D014748:Vinca Alkaloids; C021086:secologanin; C021093:strictosidine; C004259:7-azatryptamine; D006639:Histidine; D019759:Carbon-Nitrogen Lyases; C022684:strictosidine synthetase