TITLE

A Fungal α-Galactosidase from Tricholoma matsutake with Broad Substrate Specificity and Good Hydrolytic Activity on Raffinose Family Oligosaccharides

AUTHOR(S)
Xueran Geng; Guoting Tian; Yongchang Zhao; Liyan Zhao; Hexiang Wang; Tzi Bun Ng
PUB. DATE
August 2015
SOURCE
Molecules;Aug2015, Vol. 20 Issue 8, p13550
SOURCE TYPE
Academic Journal
DOC. TYPE
Article
ABSTRACT
An acidic α-galactosidase designated as TMG was purified from the fruiting bodies The purification protocol entailed ion exchange chromatography on Q-Sepharose and of Tricholoma matsutake with 136-fold purification and a specific activity of 909 units/mg. Mono-Q and fast protein liquid chromatography on Superdex 75. TMG is a monomeric protein exhibiting a molecular mass of 47 kDa in SDS-PAGE and gel filtration. The purified enzyme was identified by LC-MS/MS and three inner amino acid sequences were obtained. The optimum pH and temperature for TMG with pNPGal as substrate were pH 4.5 and 55 °C, respectively. The α-galactosidase activity was strongly inhibited by K+, Ca2+, Cd2+, Hg2+, Ag+ and Zn2+ ions. The enzyme activity was inhibited by the chemical modification agent N-bromosuccinimide (NBS), indicating the importance of tryptophan residue(s) at or near the active site. Besides hydrolyzing pNPGal, TMG also efficaciously catalyzed the degradation of natural substrates such as stachyose, raffinose, and melibiose. Thus TMG can be exploited commercially for improving the nutritional value of soy milk by degradation of indigestible oligosaccharides.
ACCESSION #
109108929

 

Related Articles

Share

Read the Article

Courtesy of THE LIBRARY OF VIRGINIA

Sorry, but this item is not currently available from your library.

Try another library?
Sign out of this library

Other Topics