Purification of an isoflavonoid 7-O-beta-apiosyl-glucoside beta-glycosidase and its substrates from Dalbergia nigrescens Kurz.
A beta-glycosidase was purified from the seeds of Dalbergia nigescens Kurz based on its ability to hydrolyse p-nitrophenyl beta-glucoside and beta-fucoside. This enzyme did not hydrolyze various glycosidic substrates efficiently, so it was used to identify its own natural substrates. Two substrates were identified, isolated and their structures determined as: compound 1, dalpatein 7-O-beta-D-apiofuranosyl-(1-->6)-beta-D-glucopyranoside and compound 2, 6,2',4',5'-tetramethoxy-7-hydroxy-7-O-beta-D-apiofuranosyl-(1-->6)-beta-D-glucopyranoside (dalnigrein7-O-beta-D-apiofuranosyl-(1-->6)-beta-D-glucopyranoside). The beta-glycosidase removes the sugar from these glycosides as a disaccharide, despite its initial identification as a beta-glucosidase and beta-fucosidase.
Chuankhayan
Phimonphan
P
Institute of Science, Suranaree University of Technology, Schools of Biochemistry and Chemistry, 111 University Avenue, Nakhon Ratchasima 30000, Thailand.
Hua
Yanling
Y
Svasti
Jisnuson
J
Sakdarat
Santi
S
Sullivan
Patrick A
PA
Ketudat Cairns
James R
JR
D002384:Catalysis; D035782:Dalbergia / Q000201:enzymology*; D004187:Disaccharides / Q000737:chemistry* / Q000378:metabolism*; D006026:Glycoside Hydrolases / Q000302:isolation & purification* / Q000378:metabolism*; D006868:Hydrolysis; D007529:Isoflavones / Q000737:chemistry* / Q000378:metabolism*; D007700:Kinetics; D012639:Seeds / Q000201:enzymology; D013379:Substrate Specificity
D004187:Disaccharides; D007529:Isoflavones; C506795:dalnigrein7-O-beta-D-apiofuranosyl-(1-6)-beta-D-glucopyranoside; C506794:dalpatein 7-O-beta-D-apiofuranosyl-(1-6)-beta-D-glucopyranoside; D006026:Glycoside Hydrolases