Biomaterial Database

beta-D-xylosidase from Bacillus pumilus PRL B12: hydrolysis of aryl beta-D-xylopyranosides. 1978

H Kersters-Hilderson, and E Van Doorslaer, and C K De Bruyne

The influence of substituents on the binding and hydrolysis of several substituted beta-D-xylopyranosides by beta-D-xylosidase from Bacillus pumilus PRL B12 has been investigated. From a comparison of the inhibition constants of 1-thio-beta-D-xylopyranosides with the apparent Michaelis-Menten constants of the substrates, it followed that the latter constants are good approximations of the true equilibrium constants. The influence of the substituent on the rate and activation parameters is small. The results are in agreement with, but do not prove, a one-step mechanism without the formation of a glycosyl-enzyme intermediate.

UI	MeSH Term	Description	Entries
D007700	Kinetics	The rate dynamics in chemical or physical systems.
D006026	Glycoside Hydrolases	Any member of the class of enzymes that catalyze the cleavage of the glycosidic linkage of glycosides and the addition of water to the resulting molecules.	Endoglycosidase,Exoglycosidase,Glycohydrolase,Glycosidase,Glycosidases,Glycoside Hydrolase,Endoglycosidases,Exoglycosidases,Glycohydrolases,Hydrolase, Glycoside,Hydrolases, Glycoside
D001407	Bacillus	A genus of BACILLACEAE that are spore-forming, rod-shaped cells. Most species are saprophytic soil forms with only a few species being pathogenic.	Bacillus bacterium
D013865	Thioglycosides
D014994	Xylose		D-Xylose,D Xylose
D014995	Xylosidases	A group of enzymes that catalyze the hydrolysis of alpha- or beta-xylosidic linkages. EC 3.2.1.8 catalyzes the endo-hydrolysis of 1,4-beta-D-xylosidic linkages; EC 3.2.1.32 catalyzes the endo-hydrolysis of 1,3-beta-D-xylosidic linkages; EC 3.2.1.37 catalyzes the exo-hydrolysis of 1,4-beta-D-linkages from the non-reducing termini of xylans; and EC 3.2.1.72 catalyzes the exo-hydrolysis of 1,3-beta-D-linkages from the non-reducing termini of xylans. Other xylosidases have been identified that catalyze the hydrolysis of alpha-xylosidic bonds.	Xylobiases,Xylan Hydrolases,Hydrolases, Xylan