Molecular characterization of two plant flavonol sulfotransferases.

摘要: Abstract cDNA clones coding for flavonol 3- and 4'-sulfotransferases (STs) were isolated by antibody screening of a cDNA expression library produced from poly(A)+ RNA extracted terminal buds Flaveria chloraefolia. Sequence analysis revealed full-length with open reading frames 933 960 base pairs, which encode polypeptides containing 311 320 amino acids, respectively. This corresponds to molecular mass 36,442 Da the 3-ST 37,212 4'-ST. Expression these in Escherichia coli led synthesis beta-galactosidase-ST fusion proteins having same substrate position specificities as those 4'-flavonol ST enzymes plant. Comparison deduced acid sequence two an overall identity 69% residues. The STs F. chloraefolia also shared significant similarities steroid aryl found animal tissues senescence marker protein 2 rat liver, suggesting evolutionary link between plant STs.