Xylanase IV, an exoxylanase of Aeromonas caviae ME-1 which produces xylotetraose as the only low-molecular-weight oligosaccharide from xylan

Abstract

A novel xylanase (xylanase IV) which produces xylotetraose as the only low-molecular-weight oligosaccharide from oat spelt xylan was isolated from the culture medium of Aeromonas caviae ME-1. By sodium dodecyl sulfate- polyacrylamide gel electrophoresis, the xylanase IV molecular weight was 41,000. Xylanase IV catalyzed the hydrolysis of oat spelt xylan, producing exclusively xylotetraose. The acid hydrolysate of the product gave D-xylose. The enzyme did not hydrolyze either p-nitrophenyl-β-D-xyloside, small oligosaccharides (xylobiose and xylotetraose), or polysaccharides, such as starch, cellulose, carboxymethyl cellulose, laminarin, and β-1,3-xylan.