ID 2.1.1.139 DE 3'-demethylstaurosporine O-methyltransferase. AN 3'-demethoxy-3'-hydroxystaurosporine O-methyltransferase. AN staurosporine synthase. CA 3'-demethylstaurosporine + S-adenosyl-L-methionine = H(+) + S-adenosyl-L- CA homocysteine + staurosporine. CC -!- Catalyzes the final step in the biosynthesis of staurosporine, CC an alkaloidal antibiotic that is a potent inhibitor of protein CC kinases, especially protein kinase C. //