RESUMO
Natural pesticides pyrethrins biosynthesized by Tanacetum cinrerariifolium are biodegradable and safer insecticides for pest insect control. TcGLIP, a GDSL lipase underpinning the ester bond formation in pyrethrins, exhibits high stereo-specificity for acyl-CoA and alcohol substrates. However, it is unknown how the enzyme recognizes the other structural features of the substrates and whether such specificity affects the product amount and composition in T. cinrerariifolium. We report here that the cysteamine moiety in (1R,3R)-chrysanthemoyl CoA and the conjugated diene moiety in (S)-pyrethrolone play key roles in the interactions with TcGLIP. CoA released from chrysanthemoyl CoA in the pyrethrin-forming reaction reduces the substrate affinity for TcGLIP by feedback inhibition. (S)-Pyrethrolone shows the highest catalytic efficiency for TcGLIP, followed by (S)-cinerolone and (S)-jasmololone, contributing, at least in part, to determine the pyrethrin compositions in T. cinerariifolium.
