1979/08/21 by Hajime Mizukami, Hans Nordlöv, Siu-Leung Lee +1 · 77 citations
Biochemistry, Genetics and Molecular Biology · Chemistry · Medicine · Pharmacology, Toxicology and Pharmaceutics · #Alkaloids: synthesis and pharmacology #Berberine and alkaloids research #Biochemistry #Biology #Catharanthus roseus #Chemistry #Enzyme #Indole test #Plant tissue culture and regeneration #Tryptamine #Vindoline
paper · doi:10.1021/bi00584a018
published in Biochemistry 18(17), 3760-3763 (American Chemical Society)
openalex publication_date 1979/08/21 · openalex created_date 2025/10/10 · openalex updated_date 2026/06/11
Strictosidine synthetase, which catalyzes the condensation of tryptamine with secologanin to form strictosidine (isovincoside), was purified 740-fold to homogeneity from cultured cells of Catharanthus roseus in 10% yield. The specific activity is 5.85 nkat/mg. The molecular weight as estimated by gel filtration is 38,000. The isoelectric point is 4.6. Apparent Km values for tryptamine and secologanin are 0.83 and 0.46 mM, respectively. The enzyme shows a broad pH optimum between 5.0 and 7.5. The product of the enzymic reaction is exclusively strictosidine, while no trace of its epimer vincoside can be detected. Sulfhydryl inhibitors have no effect on the enzyme. End products in the biosynthetic pathway of indole alkaloids such as ajmalicine, vindoline, and catharanthine do not inhibit the activity of strictosidine synthetase.