Salicylic acid biosynthesis via the PAL pathway requires benzaldehyde synthase and a benzyl salicylate-specific esterase.

ABSTRACT: Salicylic acid (SA) biosynthesis in plants occurs via the isochorismate synthase (ICS) and phenylalanine ammonia-lyase (PAL) pathways. The critical steps from benzyl-CoA to SA in the PAL-mediated pathway remain unknown. To probe benzenoid metabolism, we generated CRISPR/Cas9-mediated knockouts of benzaldehyde synthase in poplar. These plants produce less benzyl benzoate, benzyl salicylate and SA, yet accumulate more benzoic acid. We show that HSR203J encodes a carboxylesterase that specifically hydrolyzes benzyl salicylate. Virus-induced gene silencing (VIGS) of HSR203J in Nicotiana benthamiana led to reduced benzyl salicylate hydrolysis to SA. Based on these data, we propose a biosynthesis model and provide evidence that benzoyl-CoA is esterified to benzyl benzoate and converted to benzyl

SUBMITTER: Ma D 

PROVIDER: S-EPMC12574334 | biostudies-literature | 2025 Oct

REPOSITORIES: biostudies-literature