German researchers further characterize the 4 enzymes that Psilocybe uses to synthesize psilocybin. PsiD, PsiK, PsiM, and PsiH. PsiD represents a new class of fungal l-tryptophan decarboxylases. Using the enzymes, they synthesized psilocybin in the lab starting from 4-hydroxy-l-tryptophan. This paves the way for possible commercial production of the chemical.