Malonyl-coenzyme A:isoflavone 7-O-glucoside-6"-O-malonyltransferase from roots of chick pea (Cicer arietinum L.).
A malonyltransferase which catalyzes the malonylation of isoflavone 7-O-glucosides in position 6 of the glucose moiety using malonyl-coenzyme A as acyl donor has been purified 157-fold from 4-day-old roots of chick pea (Cicer arietinum L.). The enzyme showed a pH optimum of 8.0 and a molecular weight of 112,000. The Km for malonylcoenzyme A was 48 microM and, for the chick pea isoflavones biochanin A and formononetin, 36 and 24 microM, respectively. Various other isoflavone, flavone, and flavonol 7-O-glucosides and chalcone 4'-O-glucosides were much poorer substrates. Flavonol 3-O-glucosides and isoflavone 4'-O-glucosides were not malonylated by the malonyltransferase.
D000214:Acyl Coenzyme A / Q000378:metabolism; D000217:Acyltransferases / Q000302:isolation & purification / Q000378:metabolism*; D002851:Chromatography, High Pressure Liquid; D004355:Drug Stability; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D008970:Molecular Weight; D010944:Plants / Q000201:enzymology*; D013379:Substrate Specificity; D013696:Temperature
D000214:Acyl Coenzyme A; D000217:Acyltransferases; C042862:malonyl-CoA-isoflavone-7-O-glucoside-6''-O-malonyltransferase