How the magic begins: The l-tryptophan decarboxylase PsiD initiates the biosynthesis of the psychotropic natural product psilocybin in Psilocybe mushrooms. Its in vitro biochemical characterization and in silico modeling of its structure identified a non-canonical serine protease triad for autocatalytic cleavage of the proenzyme. PsiD's substrate flexibility makes it a versatile catalyst for biotechnological applications.
The l-tryptophan decarboxylase PsiD catalyzes the initial step of the metabolic cascade to psilocybin, the major indoleethylamine natural product of the “magic” mushrooms and a candidate drug against major depressive disorder. Unlike numerous pyridoxal phosphate (PLP)-dependent decarboxylases for natural product biosyntheses, PsiD is PLP-independent and resembles type II phosphatidylserine decarboxylases. Here, we report on the in vitro biochemical characterization of Psilocybe cubensis PsiD along with in silico modeling of the PsiD structure. A non-canonical serine protease triad for autocatalytic cleavage of the pro-protein was predicted and experimentally verified by site-directed mutagenesis.Zum Volltext