Biomaterial Database

Proteinase inhibitors from the excretory gland cells of Stephanurus dentatus. Purification and properties of three secretory proteinase inhibitors. 1978

M L Rhoads, and R D Romanowski, and R F Doherty, and K K Stewart

Three proteinase inhibitors designated as I, II, and III were isolated from the excretory gland cells of the swine kidney worm, Stephanurus dentatus. The inhibitors, which were trichloroacetic acid-soluble, were purified by affinity chromatography and ion exchange chromatography. The homogeneity of each inhibitor was shown by polyacrylamide gel electrophoresis and electrofocusing. The molecular weights of the inhibitors estimated by sodium dodecyl sulfate gel electrophoresis fell within a limited range of 9300 to 9700, and the isoelectric points were 6.45, 6.20, and 5.34 for Inhibitors I, II, and III, respectively. The inhibitors formed complexes with trypsin having apparent dissociation constants (Ki) of 2.9 X 10(-11), 7.6 X 10(-11), and 6.4 X 10(-11) M, respectively. Each inhibitor inhibits the esterolytic and proteolytic activities of both trypsin and chymotrypsin. A proteinase inhibitor present in the reproductive organs, intestines, body walls, and esophagi was identical with Inhibitor II found in the excretory gland cells. Culture medium collected after 24-h incubation with adult worms contained the same three inhibitors as the excretory gland cells. These data suggest that the gland cells may secrete the inhibitors internally and externally.

UI	MeSH Term	Description	Entries
D007700	Kinetics	The rate dynamics in chemical or physical systems.
D008970	Molecular Weight	The sum of the weight of all the atoms in a molecule.	Molecular Weights,Weight, Molecular,Weights, Molecular
D009348	Nematoda	A phylum of unsegmented helminths with fundamental bilateral symmetry and secondary triradiate symmetry of the oral and esophageal structures. Many species are parasites.	Phasmidia,Secernentea,Sipunculida
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
D011506	Proteins	Linear POLYPEPTIDES that are synthesized on RIBOSOMES and may be further modified, crosslinked, cleaved, or assembled into complex proteins with several subunits. The specific sequence of AMINO ACIDS determines the shape the polypeptide will take, during PROTEIN FOLDING, and the function of the protein.	Gene Products, Protein,Gene Proteins,Protein,Protein Gene Products,Proteins, Gene
D005088	Exocrine Glands	Glands of external secretion that release its secretions to the body's cavities, organs, or surface, through a duct.	Exocrine Gland,Gland, Exocrine,Glands, Exocrine
D000596	Amino Acids	Organic compounds that generally contain an amino (-NH2) and a carboxyl (-COOH) group. Twenty alpha-amino acids are the subunits which are polymerized to form proteins.	Amino Acid,Acid, Amino,Acids, Amino
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia
D014018	Tissue Distribution	Accumulation of a drug or chemical substance in various organs (including those not relevant to its pharmacologic or therapeutic action). This distribution depends on the blood flow or perfusion rate of the organ, the ability of the drug to penetrate organ membranes, tissue specificity, protein binding. The distribution is usually expressed as tissue to plasma ratios.	Distribution, Tissue,Distributions, Tissue,Tissue Distributions