Synergy between enzymes from Aspergillus involved in the degradation of plant cell wall polysaccharides

Abstract

Synergy in the degradation of two plant cell wall polysaccharides, water insoluble pentosan from wheat flour (an arabinoxylan) and sugar beet pectin, was studied using several main-chain cleaving and accessory enzymes. Synergy was observed between most enzymes tested, although not always to the same extent. Degradation of the xylan backbone by endo-xylanase and β-xylosidase was influenced most strongly by the action of α- l-arabinofuranosidase and arabinoxylan arabinofuranohydrolase resulting in a 2.5-fold and twofold increase in release of xylose, respectively. Ferulic acid release by feruloyl esterase A and 4- O-methyl glucuronic acid release by α-glucuronidase depended largely on the degradation of the xylan backbone by endo-xylanase but were also influenced by other enzymes. Degradation of the backbone of the pectin hairy regions resulted in a twofold increase in the release of galactose by β-galactosidase and endo-galactanase but did not significantly influence the arabinose release by arabinofuranosidase and endo-arabinase. Ferulic acid release from sugar beet pectin by feruloyl esterase A was affected most strongly by the presence of other accessory enzymes.