阿魏酸脱羧酶的异源表达及酶学性质表征OA

Ferulic acid decarboxylase(FDC)can biocatalyze ferulic acid to produce 4-vinylguaiacol,which was widely used in food,medicine,cosmetics and other industries.To study the enzymatic properties and catalytic function of ferulic acid decarboxylase from non-Saccharomyces yeasts,ferulic acid decarboxylase XM from Wickerhamomyces anomalus was screened from the National Center for Biotech-nology Information(NCBI)database to achieve heterologous expression in Pichia pastoris.Molecular docking of ferulic acid decarboxylase XM with four acids(caffeic,ferulic,p-coumaric,and sinapic acids)predicted five amino acid residues(tyrosine,phenylalanine,histi-dine,glutamine,and glutamate)that might change the function of ferulic acid decarboxylase XM.The results showed that the enzyme ac-tivity of the recombinant protein were(19.72±0.32)IU/mg and(136.39±2.94)IU/mg in shake flasks and in fermenters after 84 h of induction,respectively.The recombinant enzyme showed maximum activity at 40 ℃ and pH 6.0.The enzyme had broad substrate specific-ity and was able to efficiently decarboxylate four acids at a substrate concentration of 4 mmol/L.The Km values of caffeic acid,ferulic acid,p-coumaric acid,and sinapic acid were(151.94±9.30),(133.70±5.62),(152.09±5.33),and(170.89±8.76)μmol/L,respectively,and the Vmax values were(156.23±2.19),(158.16±1.52),(156.86±1.14)and(128.64±0.96)IU/mg,respec-tively.This study laid a foundation for further exploring the catalytic mechanism of ferulic acid decarboxylase XM.