Biomaterial Database

Binding of alkyl beta-D-xylopyranosides, containing branched-chain, cyclic, and substituted aglycon groups, to beta-D-xylosidase from Bacillus pumilus PRL B12. 1980

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

For a number of alkyl beta-D-xylopyranosides having branched-chain, cyclic, and substituted aglycon groups, and binding to beta-D-xylosidase from B. pumilus PRL B12, the binding constant Ki and (for some of them) the thermodynamic equilibrium parameters delta H0, delta S0, and delta G0 have been determined. Although the aglycon is bound through hydrophobic forces, no simple relationships between the binding parameters and the relative hydrophobicity of the alkyl beta-D-xylopyranosides could be demonstrated. All of the available evidence suggests that the aglycon sub-site has a highly specific structure which forces the atoms of the aglycon group to occupy well-defined positions. The supplementary energy-requirements resulting from the imposed restrictions seem to be the main reason for the irregular way in which the binding parameters depend on the aglycon structure.

UI	MeSH Term	Description	Entries
D011485	Protein Binding	The process in which substances, either endogenous or exogenous, bind to proteins, peptides, enzymes, protein precursors, or allied compounds. Specific protein-binding measures are often used as assays in diagnostic assessments.	Plasma Protein Binding Capacity,Binding, Protein
D002151	Calorimetry	The measurement of the quantity of heat involved in various processes, such as chemical reactions, changes of state, and formations of solutions, or in the determination of the heat capacities of substances. The fundamental unit of measurement is the joule or the calorie (4.184 joules). (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)
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
D013329	Structure-Activity Relationship	The relationship between the chemical structure of a compound and its biological or pharmacological activity. Compounds are often classed together because they have structural characteristics in common including shape, size, stereochemical arrangement, and distribution of functional groups.	Relationship, Structure-Activity,Relationships, Structure-Activity,Structure Activity Relationship,Structure-Activity Relationships
D013816	Thermodynamics	A rigorously mathematical analysis of energy relationships (heat, work, temperature, and equilibrium). It describes systems whose states are determined by thermal parameters, such as temperature, in addition to mechanical and electromagnetic parameters. (From Hawley's Condensed Chemical Dictionary, 12th ed)	Thermodynamic
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