Title: Predicted metabolic engineering of formation of unnatural cyanogenic glucosides in Arabidopsis

The first steps in cyanogenic glucoside synthesis are catalyzed by a multifunctional cytochrome P450 being a paralog to sorghum CYP79A1 whereas subsequent steps are catalyzed by less specific enzymes being paralogs to sorghum CYP71E1 and UGT85B1. Introduction of CYP71E1 in Arabidopsis might be expected to enable CYP71E1 to interact with the endogenous Arabidopsis CYP79s catalyzing synthesis of glucosinolates and thus mediate cyanogenic glucoside formation for the parent amino acids tryptophan,  methionine and phenylalanine and chain elongated forms of these. In Arabidopsis mutants where the glucosinolate pathway is blocked by knock-out of CYP83B1 (rnt1-1 mutant), the expression of CYP71E1 may serve to rescue the auxin over-production phenotype by redirecting the flux of indolylacetaldoxime towards production of a tryptophan derived cyanogenic glucoside and lower the flux towards indolylacetic acid production. The phenotypes and the metabolite profiles of the engineered plants are currently being analyzed.

 

Researchers involved: Marc Morant, Birger Lindberg Møller, Søren Bak

 

Financial support: Marie Curie Training Grant, Danish National Research Foundation