Cloning, over-expression and enzymatic characterization of recombinant acetyl xylan esterase from Ochrovirga pacifica S85

Abstract

Acetyl xylan esterase hydrolyzes the ester linkages of the acetyl groups in position 2 and/or 3 of the xylose moieties of natural acetylated xylan present in the hardwood. The cooperation of acetyl xylan esterase with xylanase requires for complete biodegradation of this structurally complex polymer. Acetyl xylan esterase (S85-x1) gene from O. pacifica S85T were cloned and overexpressed in E. coli expression system. The S85-x1 gene had an open reading frame of 864 bp encoding a polypeptide of 287 amino acid residues. The deduced amino acid sequence of the S85-x1 showed 35.1% similarity with both endo-1,4-β-xylanase B from Robiginitalea biformata HTCC2501, and endo-1,4-β-xylanase from Mesoflavibacter zeaxanthinifaciens. The calculated molecular mass of protein was 32 kDa. Optimum conditions and specific activity of purified his-tagged S85-x1 were checked. The recombinant acetyl xylan esterase showed no activity against xylan. However, xylanase activity was markedly enhanced in the presence of acetyl xylan esterase. S85-x1 can be used alongside xylanase to take advantage of this synergistic effect during industrial applications.complete biodegradation of this structurally complex polymer. Acetyl xylan esterase (S85-x1) gene from O. pacifica S85T were cloned and overexpressed in E. coli expression system. The S85-x1 gene had an open reading frame of 864 bp encoding a polypeptide of 287 amino acid residues. The deduced amino acid sequence of the S85-x1 showed 35.1% similarity with both endo-1,4-β-xylanase B from Robiginitalea biformata HTCC2501, and endo-1,4-β-xylanase from Mesoflavibacter zeaxanthinifaciens. The calculated molecular mass of protein was 32 kDa. Optimum conditions and specific activity of purified his-tagged S85-x1 were checked. The recombinant acetyl xylan esterase showed no activity against xylan. However, xylanase activity was markedly enhanced in the presence of acetyl xylan esterase. S85-x1 can be used alongside xylanase to take advantage of this synergistic effect during industrial applications.