Sinapis phylogeny and evolution of glucosinolates and specific nitrile degrading enzymes

The crucifers Sinapis alba and Sinapis arvensis are distantly related but both contain 4-hydroxybenzylglucosinolate (sinalbin) and enzymatic activity converting the corresponding nitrile to amide and carboxylic acid. Distribution of 4-hydroxyphenylacetonitrile degrading activity and 27 glucosinolates in the genus Sinapis and related species is presented. The specificity of the reaction and low nitrile degrading activity in related species both with and without sinalbin, suggest a facultative metabolic connection with sinalbin that evolved twice.