1 Answers
Strictosidine synthase a key enzyme in alkaloid biosynthesis. It catalyses the condensation of tryptamine with secologanin to form strictosidine in a formal Pictet–Spengler reaction:
Thus, the two substrates of this enzyme are tryptamine and secologanin, whereas its two products are 3-alpha-strictosidine and H2O. Since the condensation of tryptamine and secologanin is the first committed step in alkaloid synthesis, strictosidine synthase plays a fundamental role for the great majority of the indole-alkaloid pathways.
This enzyme belongs to the family of lyases, specifically amine lyases, which cleave carbon-nitrogen bonds. It can be isolated from several alkaloid-producing plants from the family Apocynaceae. The systematic name of this enzyme class is 3-alpha-strictosidine tryptamine-lyase. Other names in common use include strictosidine synthetase, STR, and 3-alpha-strictosidine tryptamine-lyase. Originally isolated from the plant Rauvolfia serpentina, a medicinal plant widely used in Indian folk medicine, this enzyme participates in terpenoid biosynthesis and indole and ipecac alkaloid biosynthesis, both of which produce many compounds with significant physiological and medicinal properties.