Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P06889 (Mol)
 630,302 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

In Ciona intestinalis a chymotrypsin-like activity is involved in sperm penetration of the egg vitelline coat. A chymotrypsin-like enzyme has been purified from spermatozoa by a protocol including ion exchange chromatography, gel filtration, and native polyacrylamide gel electrophoresis. The purified enzyme resulted homogeneous when analyzed by SDS-PAGE. The molecular weight of the chymotrypsin-like enzyme was estimated to be 35 kDa by gel filtration and 24 KDa by SDS-PAGE in nonreducing conditions. The pH optimum of the enzyme is 8.4 and its activity is enhanced by Ca2+. It shows the highest activity towards the synthetic substrate Suc-Ala-Ala-Pro-Phe-AMC. Furthermore, by electron microscopy, the purified enzyme affects the structure of egg vitelline coat, and thus it fulfills one of the criteria of a lysin.
Mol Reprod Dev 1992 Aug
PMID:Purification and characterization of a vitelline coat lysin from Ciona intestinalis spermatozoa. 149 86

The egg jelly-induced acrosome reaction of the sea urchin, Strongylocentrotus intermedius, was inhibited by succinyl-Leu-Leu-Val-Tyr-4-methyl-coumaryl-7-amide (Suc-Leu-Leu-Val-Tyr-MCA), but not by Suc-Ala-Ala-Pro-Phe-MCA. The proteases with hydrolytic activity toward the former were purified from sperm extract by DEAE-Sephacel and hydroxylapatite chromatographies, Sephacryl S-300 gel filtration, and heparin-Sepharose CL-6B chromatography. Two types of protease were separated, and the molecular weights were estimated to be 65 and 700 kDa, respectively, by gel filtration. The former was accompanied by hydrolytic activity toward Suc-Ala-Ala-Pro-Phe-MCA, which was not hydrolyzed by the latter. Polyacrylamide gel electrophoresis of 700 kDa protease gave a single protein band under nondenaturing conditions and at least eight bands in the range of 22-33 kDa in the presence of sodium dodecyl sulfate (SDS). The substrate specificity and the inhibitor sensitivity of 700 kDa protease indicate that it contains two types of the activity, one is chymotrypsin-type and the other trypsin-type. The former activity was enhanced by poly-L-lysine or SDS. These properties of 700 kDa protease are similar to those of proteasomes (multicatalytic proteinases) isolated from various eukaryotic sources. We had previously shown that inhibitors of chymotrypsin-like proteases inhibit the increase of intracellular Ca2+ concentration by egg jelly, resulting in the inhibition of the acrosome reaction of St. intermedius (Matsumura and Aketa, Gamete Res 23:255-266, 1989). Bringing these findings together, we suggest that the chymotrypsin-like activity of sperm proteasome participates in the onset of the acrosome reaction of St. intermedius.
Mol Reprod Dev 1991 Jun
PMID:Proteasome (multicatalytic proteinase) of sea urchin sperm and its possible participation in the acrosome reaction. 187 26

High molecular weight, multicatalytic proteinases (named proteasomes) have been for the first time found, on the basis of different protein patterns, in the cytoplasmic soluble fractions of both non-hormone-treated (premature) and progesterone-treated (mature) oocytes of a frog (Rana pipiens). These enzymes, pooled separately as two fractions sedimenting between around 19S and the bottom (over 27S) on glycerol density gradient centrifugation, were composed of several molecular forms with apparent high molecular weights ranging from over 700 kDa, as judged on Sepharose 6B gel filtration. In addition, both the fractions hydrolyzed distinctly a Tyr-containing substrate in the presence of SDS as an activator, and exhibited higher activities toward Arg-containing substrates in the absence of SDS, and activity toward a Glu-containing substrate in the presence and absence of SDS. Immunological experiments using antibodies against proteasomes purified from ovaries of Xenopus laevis clearly revealed characteristic cross-reactivity with both the fractions found in Rana. These data suggest that these enzymes in the two fractions from the respective oocytes in Rana are very similar or identical to the proteasomes of Xenopus. The enzymes in premature oocytes eluted at 0.15-0.18M NaCl on a DEAE-cellulose column disappeared on treatment with TPCK, a well-known chymotrypsin inhibitor, suggesting that the 0.15-0.18M NaCl-eluate contained chymotrypsin-like proteinases probably latent in ovo. The enzymes in mature oocytes had not similar chromatographical patterns to those in premature oocytes. These results suggest that the enzymes already present in premature oocytes may be involved through conformational alterations as to the protein pattern in oocyte maturation following induction by progesterone.
Mol Cell Biochem 1991 Feb 02
PMID:High molecular weight-multicatalytic proteinases in premature and mature oocytes of Rana pipiens. 200 78

Recent studies have led to a rapid expansion of knowledge concerning the structure and biology of the two major mast cell proteinases, tryptase and chymase. Tryptase is an abundant, trypsin-like enzyme found in the secretory granules of all human lung mast cells. The subunits of the heparin-associated tryptase tetramer appear to be the products of a multigene family whose intron-exon organization is unique and is not closely related to that of other mast cell or leukocyte serine proteinases. In vitro studies suggest that tryptases may participate in lung and airway responses by regulating airway neuropeptide activity, bronchomotor tone, and fibroblast mitogenesis. Mast cell chymases are chymotrypsin-like proteinases related closely to neutrophil cathepsin G and lymphocyte granzymes. The cDNA-derived structures of tryptase and chymase suggest that the two enzymes may differ in modes of activation from proenzyme forms, although the mature enzymes are packaged and released together. Chymase expression appears to be limited to a subset of human lung mast cells most prevalent in the airway submucosa. Possible roles for chymase include inactivation of sensory neuropeptides, regulation of submucosal gland secretion, and potentiation of histamine-induced vascular permeability.
Am J Respir Cell Mol Biol 1991 May
PMID:The structure and airway biology of mast cell proteinases. 202 78

In Ciona intestinalis, sperm penetration through the egg vitelline coat is an essential event of fertilization. We investigated whether trypsin- and chymotrypsin-like enzymes are involved in this event. Inhibitors and peptide substrates for chymotrypsin-like enzymes blocked the overall process of fertilization in a concentration-dependent manner. The inhibitory activity was specifically exerted on the step of sperm penetration. Chymotrypsin-like protease activity was identified in spermatozoa with the fluorogenic synthetic substrate Suc-Ala-Ala-Phe-AMC, which was the most effective substrate in blocking sperm penetration. These data indicate that a chymotrypsin-like protease activity is a sperm lysin of Ciona intestinalis.
Mol Reprod Dev 1990 Aug
PMID:Chymotrypsin-like enzymes are involved in sperm penetration through the vitelline coat of Ciona intestinalis egg. 222 80

Factors that modulate neutrophil migration into the lung are poorly understood. However, there is evidence that neutrophil activation by formylmethionylleucylphenylalanine (FMLP) depends upon a surface proteinase with chymotrypsin-like activity. This suggests that chymotrypsin inhibitors such as alpha-1-proteinase inhibitor (alpha 1PI) could modify neutrophil migration in response to FMLP. We have studied neutrophil chemotaxis using the multiple blind well assay system. This article presents evidence that alpha 1PI is an inhibitor of neutrophil migration in response to FMLP. The effect is related to the inhibitory function of the protein. Alpha-1-antichymotrypsin is more potent than alpha 1PI as an inhibitor of this movement, whereas antileukoprotease is less potent. The results suggest that a cell membrane-bound serine proteinase (perhaps cathepsin G) is necessary for the enhancement of cell movement after receptor binding of FMLP. Oxidized alpha 1PI or a 4,000-D peptide cleaved from alpha 1PI by porcine pancreatic elastase or human neutrophil elastase are capable of enhancing cell motility. The results suggest that alpha 1PI may play a role in cell migration into the lung during acute inflammatory process.
Am J Respir Cell Mol Biol 1990 Feb
PMID:Effect of alpha-1-proteinase inhibitor on neutrophil chemotaxis. 230 72

Analysis of amino acid sequences of barley stripe mosaic virus (BSMV) proteins revealed the pentapeptide GDSGG, the sequence unique for catalytic centers of serine chymotrypsin-like proteases, in protein p14 encoded by open reading frame 4 of RNA beta. Computer-assisted comparisons revealed a statistically significant similarity between amino acid sequences of p14 and chymotrypsin-like proteases. The catalytic His and Asp residues tentatively identified in p14 together with the Ser residue of the GDSGG sequence, presumably, constitute the "catalytic triad" characteristic of chymotrypsin-like proteases. Based on these observations and on the presence of a potential N-proximal transmembrane domain in p14, this protein may be suggested to be a serine protease involved in processing of the replicase precursor within a membrane-bound replication complex of BSMV.
Mol Gen Mikrobiol Virusol 1989 Jun
PMID:[Amino acid sequence analysis of barley stripe mosaic viral proteins: tentative identification of viral serine proteases]. 281 97

The ability of synthetic inhibitors of trypsin-like (TLCK) and chymotrypsin-like (TPCK) proteinases and natural antiproteinase oligopeptides of animal (aprotinin) and microbial (enzistatin) origin to suppress multicycle replication of different alpha viruses (Semliki, Sindbis, Venezuelan equine encephalomyelitis viruses) in cultured cells was studied. Antiviral activity was found to be induced by TPCK and aprotinin (Gordox). These compounds were shown to reduce virus yield 100-fold and to prevent the involvement of cells into infection process. The mechanisms of antiviral activity and chemotherapeutic possibilities of antiproteinase compounds are discussed.
Mol Gen Mikrobiol Virusol 1985 Dec
PMID:[Antiviral activity of proteinase inhibitors in cultured cells infected with alpha-viruses]. 302 88

This review summarizes our knowledge of pituitary endopeptidases. Emphasis has been placed on well-characterized enzymes and their potential roles in proteolytic processes of the pituitary. Because of space limitations, degradation of biologically active peptide by crude preparations has generally not been discussed. Only a few proteolytic enzymes are at present adequately characterized, and knowledge of their physiological function in vivo is insufficient. Among the many functions of proteolytic enzymes, those that are specific for the pituitary as an endocrine gland are of primary interest. Such functions include inactivation of neuropeptides and factors that control the secretory function of the pituitary, processing of precursors destined for secretion, selective cleavage of prohormones into active fragments, and degradation of inactive fragments. While some of the enzymes described here, such as cathepsin D, could be expected to have primarily a degradative function, others could potentially be involved in hormonal metabolism, since they exhibit trypsin-like, chymotrypsin-like, and dipeptidyl carboxypeptidase-like activities, all potentially useful in hormonal conversions. Data suggestive of the presence in the pituitary of enzymes involved in removal of the 'signal sequence', and enzymes involved in hormone processing by cleavage of bonds after a pair of basic residues and in the subsequent removal of these residues by a carboxypeptidase B-like activity have been published. None of these enzymes, however, has been isolated or purified to a degree that would allow determination of its specificity, mechanisms of action, physicochemical properties, and susceptibility to specific inhibitors. Questions that remain unresolved ask whether differences in the processing pathways in various anatomical parts of the pituitary are due to the presence of proteases with different specificities, or to different disposition of these enzymes, and factors, such as conformation of the substrate and its secondary modification, for example by glycosylation or phosphorylation. Proof of a functional involvement of a protease in hormonal processing should include demonstration that inhibition of activity results in inhibition of processing in the intact cell. Specific inhibitors of processing enzymes could potentially be used to modulate pituitary function, and thus have pharmacological interest. Although there are few answers to the above problems at present, the questions are well defined, and it can be expected that the rapidly expanding research on pituitary proteases will soon provide some of the answers.
Mol Cell Biochem 1983
PMID:Pituitary endopeptidases. 634 52

Cathepsin G, the chymotrypsin-like enzyme from human polymorphonuclear leukocytes, cleaves human IgM and produces two major fragments that closely resemble those released by leukocyte elastase digestion of IgM. An F(ab)2 mu-like fragment, mol. wt 140,000, retains some reactivity with an anti-Fc mu antiserum and is antigenically deficient with respect to the IgM subunit. The other fragment is an Fab mu-like product with a mol. wt of 54,000. Both cathepsin G fragments are indistinguishable from the elastase counterparts by immunochemical analysis. An Fc mu fragment could not be recovered. The kinetic course of the cleavage shows that cathepsin G produces Fab mu fragments at a higher rate than F(ab)2 mu, whereas the contrary is valid for elastase. Beside the two major fragments and low mol. wt peptides, cathepsin G releases also a product with the same mol. wt and immunological reactivity as the IgM subunit. The biological significance of the interaction between IgM and leukocyte proteinases is discussed.
Mol Immunol 1982 May
PMID:Cathepsin G from human polymorphonuclear leukocytes cleaves human IgM. 692 88


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