Increased transglycosylation activity of Rhodotorula glutinis endo-beta-glucanase in media containing organic solvent

The transglycosylation of p-nitrophenyl-beta -D-cellotrioside to cellotetra ose catalyzed by endo-1,4-beta -glucanase (cellulase, EC 3.2.1.4) from a ps ychrotrophic yeast, Rhodotorula glutinis KUJ 2731, was increased by additio n of a miscible organic solvent in the reaction mixture. Among various orga nic solvents tested, acetone was most effective. The transglycosylation act ivity increased with an increase in acetone concentrations, while hydrolysi s activity was suppressed. The transglycosylation preferably occurred at ac idic pH with the optimum pH at 2 in 10 mm Gly-HCl buffer. The optimum tempe rature of transglycosylation was found to be 50 degreesC in the presence of 40% acetone.