Abstract
Hundreds and thousands varieties of anthocyanin molecules are generated by complicated and diverse modification with glycosyl and acyl moieties. It has been reported that glycosyl and acyl modifications to anthocyanidins catalyzed by transferases using UDP-glycoside and acyl-CoA, respectively, as donor molecules in cytosol. Recent researches on the mechanism of acyl modification have revealed that plants have the other type of the aliphatic and aromatic acyltransferases located in vacuoles, which use acyl-glucose as a donor. In case of glucosyltransfers, the enzyme activities has not been detected to 5 and 7 positions of anthocyanins in carnation and delphinium, respectively, using UDP-glucose as a donor. We purified a glucosyl-donor molecule from petals of carnation and succeeded to detect glucosyltransferase activity to 5 position of anthocyanin in the crude extract prepared from petals of carnation. The protein for this glucosyltransferase was purified and its partial amino acid sequences were determined. Using the degenerated primers based on the amino acid sequences, we succeeded to isolate a cDNA corresponding to the amino acid sequences from carnation.
