Open AccessPurification and characterization of two xylanases from Trichoderma longibrachiatum
Author(s) -
ROYER John C.,
NAKAS James P.
Publication year - 1991
Publication title -
european journal of biochemistry
Language(s) - English
Resource type - Journals
eISSN - 1432-1033
pISSN - 0014-2956
DOI - 10.1111/j.1432-1033.1991.tb16404.x
Subject(s) - xylobiose , xylanase , xylan , xylose , carboxymethyl cellulose , chemistry , biochemistry , enzyme , hydrolysis , organic chemistry , fermentation , sodium
Two endoxylanases were purified from the culture medium of Trichoderma longibrachiatum . Both enzymes were highly basic, and lacked activity on carboxymethyl‐cellulose. An enzyme of 21.5 kDa (xylanase A) had a specific activity of 510 U/mg protein, a K m of 0.15 mg soluble xylan/ml, possessed transglycosidase activity and generated xylobiose and xylotriose as the major endproducts from xylan or xylose oligomers. A larger enzyme of 33 kDa (xylanase B) had a specific activity of 131 U/mg protein, a K m of 0.19 mg soluble xylan/ml, lacked detectable transglycosidase activity and generated xylobiose and xylose as major endproducts from xylan and xylose oligomers. Xylotriose was the smallest oligomer attacked by both enzymes. In addition, xylotriose inhibited hydrolysis of xylopentanose by both enzymes, while xylobiose appeared to inhibit xylanase B, but not xylanase A.