Mechanistic basis for the evolution of chalcone synthase catalytic cysteine reactivity in land plants.

ABSTRACT: Flavonoids are important polyphenolic natural products, ubiquitous in land plants, that play diverse functions in plants' survival in their ecological niches, including UV protection, pigmentation for attracting pollinators, symbiotic nitrogen fixation, and defense against herbivores. Chalcone synthase (CHS) catalyzes the first committed step in plant flavonoid biosynthesis and is highly conserved in all land plants. In several previously reported crystal structures of CHSs from flowering plants, the catalytic cysteine is oxidized to sulfinic acid, indicating enhanced nucleophilicity in this residue associated with its increased susceptibility to oxidation. In this study, we report a set of new crystal structures of CHSs representing all five major lineages of land plants (bryophytes, lyco

SUBMITTER: Liou G 

PROVIDER: S-EPMC6290136 | biostudies-literature | 2018 Nov

REPOSITORIES: biostudies-literature