Gene characterization, cloning and over-expression of the acetyl xylan esterase from Ochrovirga pacifica

Abstract

We isolated novel genus strain from seaweed included seawater from coastal area of Chuuk state in Micronesia, and named Ochrovirga pacifica in family Flavobacteriaceae. Genome was analyzed from the strain by genome sequencer-FLX. Acetyl xylan esterase gene (Axe) was detected from the genome. Acetyl xylan esterase hydrolyzes ester linkages of acetic acid in xylan polysaccharide. It is known to help xylanase activity. The Axe was 864 bp which is encoding 287 amino acids. The deduced amino acid sequence of the Axe showed 35.1% similarity with both endo-1,4-β-xylanase B from Robiginitalea biformata HTCC2501. It has a theoretical molecular mass and an isoelectric point (pI) of 32 kDa and 5.9, respectively. The mature protein displays the catalytic residues classically found in the enzymes belonging to GH16 family. We cloned Axe into pET11a vector and expressed in E. coli BL21(DE3). Purified his-tagged acetyl xylan esterase checked optimum conditions and specific activity.an esterase gene (Axe) was detected from the genome. Acetyl xylan esterase hydrolyzes ester linkages of acetic acid in xylan polysaccharide. It is known to help xylanase activity. The Axe was 864 bp which is encoding 287 amino acids. The deduced amino acid sequence of the Axe showed 35.1% similarity with both endo-1,4-β-xylanase B from Robiginitalea biformata HTCC2501. It has a theoretical molecular mass and an isoelectric point (pI) of 32 kDa and 5.9, respectively. The mature protein displays the catalytic residues classically found in the enzymes belonging to GH16 family. We cloned Axe into pET11a vector and expressed in E. coli BL21(DE3). Purified his-tagged acetyl xylan esterase checked optimum conditions and specific activity.