Biomaterial Database

Primary structure and inhibitory properties of a proteinase inhibitor produced by Streptomyces cacaoi. 1994

S Kojima, and M Terabe, and S Taguchi, and H Momose, and K Miura

Institute for Biomolecular Science, Gakushuin University, Tokyo, Japan.

Protein proteinase inhibitors showing sequence homology with Streptomyces subtilisin inhibitor (SSI) have been found to be distributed widely in Streptomyces species, and accordingly have been named SSI-like (SIL) proteins. SIL1 from S. cacaoi was the first of these proteins to be isolated and to be given a serial number. To study the structure-function relationship of SIL proteins, we determined the primary structure of SIL1 and measured its inhibitory activities. It was found to be composed of 110 amino acids and to exist in dimer form. The amino-acid sequence of SIL1 was unique among other characterized SIL proteins in having a one-residue deletion in two regions and a three-residue insertion in the flexible loop region. Sequence comparison indicated that SIL1 was distantly related to other members of the SSI family, and that amino-acid replacements had occurred not only on the surface of the SIL1 molecule but also in the beta-sheet region. The reactive site of SIL1 was considered to be Arg70-Glu71 from sequence alignment with other SSI-family inhibitors. SIL1 inhibited subtilisin BPN' strongly with an inhibitor constant (Ki) of 2.8 x 10(-11) M, like other members of the SSI family possessing an Arg residue at the P1 site. In contrast, SIL1 exhibited weak inhibition toward trypsin with a Ki value of 5.5 x 10(-8) M, possibly as a consequence of insertion of the three residues in the flexible loop region near the reactive site. This contrast seems to be due to the difference in the subsite structure of the two proteinases.

UI	MeSH Term	Description	Entries
D008969	Molecular Sequence Data	Descriptions of specific amino acid, carbohydrate, or nucleotide sequences which have appeared in the published literature and/or are deposited in and maintained by databanks such as GENBANK, European Molecular Biology Laboratory (EMBL), National Biomedical Research Foundation (NBRF), or other sequence repositories.	Sequence Data, Molecular,Molecular Sequencing Data,Data, Molecular Sequence,Data, Molecular Sequencing,Sequencing Data, Molecular
D011480	Protease Inhibitors	Compounds which inhibit or antagonize biosynthesis or actions of proteases (ENDOPEPTIDASES).	Antiprotease,Endopeptidase Inhibitor,Endopeptidase Inhibitors,Peptidase Inhibitor,Peptidase Inhibitors,Peptide Hydrolase Inhibitor,Peptide Hydrolase Inhibitors,Peptide Peptidohydrolase Inhibitor,Peptide Peptidohydrolase Inhibitors,Protease Antagonist,Protease Antagonists,Antiproteases,Protease Inhibitor,Antagonist, Protease,Antagonists, Protease,Hydrolase Inhibitor, Peptide,Hydrolase Inhibitors, Peptide,Inhibitor, Endopeptidase,Inhibitor, Peptidase,Inhibitor, Peptide Hydrolase,Inhibitor, Peptide Peptidohydrolase,Inhibitor, Protease,Inhibitors, Endopeptidase,Inhibitors, Peptidase,Inhibitors, Peptide Hydrolase,Inhibitors, Peptide Peptidohydrolase,Inhibitors, Protease,Peptidohydrolase Inhibitor, Peptide,Peptidohydrolase Inhibitors, Peptide
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
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
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
D014357	Trypsin	A serine endopeptidase that is formed from TRYPSINOGEN in the pancreas. It is converted into its active form by ENTEROPEPTIDASE in the small intestine. It catalyzes hydrolysis of the carboxyl group of either arginine or lysine. EC 3.4.21.4.	Tripcellim,Trypure,beta-Trypsin,beta Trypsin
D016415	Sequence Alignment	The arrangement of two or more amino acid or base sequences from an organism or organisms in such a way as to align areas of the sequences sharing common properties. The degree of relatedness or homology between the sequences is predicted computationally or statistically based on weights assigned to the elements aligned between the sequences. This in turn can serve as a potential indicator of the genetic relatedness between the organisms.	Sequence Homology Determination,Determination, Sequence Homology,Alignment, Sequence,Alignments, Sequence,Determinations, Sequence Homology,Sequence Alignments,Sequence Homology Determinations