Biomaterial Database

Importance of the carboxyl-terminal four amino acid residues in the inhibitory activity of Streptomyces subtilisin inhibitor (with a revision of its carboxyl-terminal sequence). 1980

M Sakai, and S Odani, and T Ikenaka

The carboxyl-terminal amino acid sequence of Streptomyces subtilisin inhibitor (SSI) was reinvestigated by analysis of the amino acid sequences of the thermolysin peptides from the C-terminal decapeptide, and the sequence -Val110-Ala-Phe-Phe113, which was reported in J. Biochem. 76, 1191-1209 (1974), was revised to -Val110-Phe-Ala-Phe113. Carboxypeptidase A digestion of SSI resulted in loss of the inhibitory activity in parallel with the release of the carboxyl-terminal four amino acid residues. The resulting modified inhibitor, des(Val110-Phe113)-SSI, possessed almost full inhibitory activity against subtilisin BPN' when the inhibitor was incubated with the enzyme in amounts less than one mol of enzyme per mol of the inhibitor. However, no inhibitor activity was observed when the molar ratio of the inhibitor to the enzyme was less than one. This phenomenon suggests that the carboxyl-terminal four amino acid residues might play an important role in the maintenance of the three-dimensional structure of SSI, which resists the action of the proteinase. The addition of more than 30-fold molar excess of SSI-(104-113)-decapeptide (C-terminal decapeptide of SSI) to the modified inhibitor resulted in refolding of the polypeptide chain, rendering it immune from proteolytic digestion.

UI	MeSH Term	Description	Entries
D011487	Protein Conformation	The characteristic 3-dimensional shape of a protein, including the secondary, supersecondary (motifs), tertiary (domains) and quaternary structure of the peptide chain. PROTEIN STRUCTURE, QUATERNARY describes the conformation assumed by multimeric proteins (aggregates of more than one polypeptide chain).	Conformation, Protein,Conformations, Protein,Protein Conformations
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
D001426	Bacterial Proteins	Proteins found in any species of bacterium.	Bacterial Gene Products,Bacterial Gene Proteins,Gene Products, Bacterial,Bacterial Gene Product,Bacterial Gene Protein,Bacterial Protein,Gene Product, Bacterial,Gene Protein, Bacterial,Gene Proteins, Bacterial,Protein, Bacterial,Proteins, Bacterial
D013302	Streptomyces	A genus of bacteria that form a nonfragmented aerial mycelium. Many species have been identified with some being pathogenic. This genus is responsible for producing a majority of the ANTI-BACTERIAL AGENTS of practical value.
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
D013381	Subtilisins	A family of SERINE ENDOPEPTIDASES isolated from Bacillus subtilis. EC 3.4.21.-	Alcalase,AprA-Subtilisin,Bacillus amyloliquefaciens Serine Protease,Bacillus subtilis Alkaline Proteinase,Carlsberg Subtilisin,Maxatase,Nagarse,Novo Alcalase,Profezim,Protease VII,Subtilisin 72,Subtilisin A,Subtilisin BPN',Subtilisin Carlsberg,Subtilisin DY,Subtilisin E,Subtilisin GX,Subtilisin Novo,Subtilopeptidase A,Alcalase, Novo,AprA Subtilisin,Subtilisin, Carlsberg