TITLE:
Breakdown of Corn Fiber by a Metagenomic Ferulolyl Esterase in Combination with Glycosyl Hydrolases
AUTHORS:
Dominic W. S. Wong, Victor J. Chan, Hans Liao
KEYWORDS:
Feruloyl Esterase, Ferulic Acid Esterase, Ferulic Acid, Metagenomics, Corn Fiber
JOURNAL NAME:
Advances in Enzyme Research,
Vol.9 No.4,
December
30,
2021
ABSTRACT: A feruloyl esterase (FAE-C6) gene of 957 bp was
isolated from rumen microbial metagenome, subcloned into pET32b vector, and
expressed in Escherichia coli.
The enzyme purified in active form, consisted of 319 amino acid residues, with
a molecular weight of 43.7 based on SDS-PAGE. Homology modeling showed that the
FAE contained the catalytic triad composed of Ser154-Asp263His295 and a classical Gly-X-Ser154-X-Gly nucleophile motif commonly found
in esterases. The FAE-C6 was characterized using corn fiber as substrate. Its
combining action with glycoside hydrolases (C, X, A) individually and in
various combinations was studied with focus on the difference in the effects on FA and sugar release. Glycoside
hydrolases with endo-xylanase included in the enzyme mixture showed significant
impact on increasing the FA yield. For the release of sugar, FAE enhanced the
yield in all hydrolase combinations moderately and endo-xylanase was not the
key factor in the enzyme formulation.