Biomaterial Database

The active centers of Streptomyces griseus protease 3 and alpha-chymotrypsin. Enzyme-substrate interactions beyond subsite S'1. 1976

C A Bauer

A series of N-acetylated tetra- to heptapeptide amides has synthesized for the study of enzyme-substrate interactions beyond the S1' subsite in Streptomyces griseus Protease 3 (SGP3) and alpha-chymotrypsin (EC 3.4.21.1). Evidence was obtained that S2'-P2' enzyme-substrate interactions can play a significant role for the rate of substrate hydrolysis in both enzymes. No important interaction could be demonstrated beyond the nitrogen atom of residue P3'. This provides supplementary evidence that the active site of SGP3 extends over 6-7 subsites and that of alpha-chymotrypsin over 5-6 subsites. SGP3 is a considerably more efficient protease than alpha-chymotrypsin, kcat/Km being approximately 5-10(6) S-1-M-1 for the best substrates, thus being about 100 times higher than for alpha-chymotrypsin. However, an analysis of the kinetic data indicates that, for both enzymes, the acylation rates for the best peptide substrates approach their deacylation rates.

UI	MeSH Term	Description	Entries
D007700	Kinetics	The rate dynamics in chemical or physical systems.
D008433	Mathematics	The deductive study of shape, quantity, and dependence. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)	Mathematic
D009842	Oligopeptides	Peptides composed of between two and twelve amino acids.	Oligopeptide
D010447	Peptide Hydrolases	Hydrolases that specifically cleave the peptide bonds found in PROTEINS and PEPTIDES. Examples of sub-subclasses for this group include EXOPEPTIDASES and ENDOPEPTIDASES.	Peptidase,Peptidases,Peptide Hydrolase,Protease,Proteases,Proteinase,Proteinases,Proteolytic Enzyme,Proteolytic Enzymes,Esteroproteases,Enzyme, Proteolytic,Hydrolase, Peptide
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
D002918	Chymotrypsin	A serine endopeptidase secreted by the pancreas as its zymogen, CHYMOTRYPSINOGEN and carried in the pancreatic juice to the duodenum where it is activated by TRYPSIN. It selectively cleaves aromatic amino acids on the carboxyl side.	Alpha-Chymotrypsin Choay,Alphacutanée,Avazyme
D000595	Amino Acid Sequence	The order of amino acids as they occur in a polypeptide chain. This is referred to as the primary structure of proteins. It is of fundamental importance in determining PROTEIN CONFORMATION.	Protein Structure, Primary,Amino Acid Sequences,Sequence, Amino Acid,Sequences, Amino Acid,Primary Protein Structure,Primary Protein Structures,Protein Structures, Primary,Structure, Primary Protein,Structures, Primary Protein
D001665	Binding Sites	The parts of a macromolecule that directly participate in its specific combination with another molecule.	Combining Site,Binding Site,Combining Sites,Site, Binding,Site, Combining,Sites, Binding,Sites, Combining
D013305	Streptomyces griseus	An actinomycete from which the antibiotics STREPTOMYCIN, grisein, and CANDICIDIN are obtained.
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