Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.4.21.4 (trypsin)
 42,187 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Three natural proteinase isoinhibitors with low isoelectric points BUSI I A (pI = 3.9), BUSI I B1 (pI = 3.4 and BUSI I B2 (pI = 3.7) were isolated from bull seminal plasma by gel filtration on Sephadex G-50 and ion exchange chromatography on DEAE-Sephadex and SE-Sephadex. Isoinhibitors Bl and B2 have identical amino acid composition. Isoinhibitor A contains six amino acid residues less than isoinhibitors B1 and B2. Since sugars have been detected in the isoinhibitors, heterogeneity may also be due to the sugar component. The isoinhibitors show the same inhibitory properties; all of them inhibit acrosin, trypsin and chymotrypsin. Glandular kallikrein is also inhibited, but to a very low extent only. The molecular weight (Mr approximately 8 900) was determined by gel filtration.
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PMID:Isolation of acidic acrosin isoinhibitors (BUSI I A, BUSI IB1 and BUSI I B2) from bull seminal plasma. 39 5

Antibodies obtained from guinea pigs injected with rabbit pancreatic trypsin together with antibodies raised in rabbits against bovine acrosin or bovine pancreatic trypsin were reacted against various mammalian trypsins and acrosins in double diffusion tests. The results of immunodiffusion analyses reveal antigenic dissimilarity between rabbit acrosin and rabbit trypsin.
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PMID:Rabbit acrosin: immunological dissimilarity to rabbit trypsin (1). 41 15

The effects of trypsin inhibitors and phospholipase inhibitors on the acrosome reaction of washed cauda epididymal sperm of golden hamsters were studied using two different incubation systems. One incubation system, a non-synchronous acrosome reaction inducing system, included the use of a highly purified BSA and a protein-free motility factor preparation from hamster adrenal gland. The other system was a relatively synchronous acrosome reaction-inducing-system utilizing the calcium ionophore A23187. Acrosome reactions were inhibited by three low molecular weight synthetic trypsin inhibitors, benzamidine, NPGB and TLCK, when they were added five minutes prior to the initial occurrence of acrosome reactions in the non-synchronous system or five minutes prior to induction of acrosome reactions by A23187 in the synchronous system. Two phospholipase A inhibitors, p-bromophenacyl bromide and mepacrine, were also effective in inhibiting hamster sperm acrosome reactions in both incubation systems. TPCK, an inhibitor of several non-trypsin-like proteases, indomethacin, a prostaglandin synthetase inhibitor, and soybean trypsin inhibitor, a large molecular weight polypeptide, did not inhibit acrosome reactions. The inhibition of those acrosome reactions induced by A23187 provides further indirect evidence that the effective inhibitors were functioning at a site within the sperm. The overall results provide: (1) further support for our earlier work suggesting the involvement of an internal trypsin-like enzyme (presumably acrosin) rather than an exogenous trypsin-like enzyme in the hamster sperm acrosome reaction and (2) the first evidence suggesting the possibility that a sperm phospholipase may also be involved in the mammalian acrosome reaction.
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PMID:Further evidence in support of a role for hamster sperm hydrolytic enzymes in the acrosome reaction. 57 94

Gelatinolytic activity of whole mouse spermatozoa was demonstrated by the gelatin film test. The presence of a trypsin-like protease (acrosin) in acidic extracts of mouse spermatozoa was shown by an electrophoretic method to separate the enzyme from a putative inhibitor.
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PMID:Demonstration of acrosin in mouse spermatozoa. 64 3

A survey of the reactivity of 16 peptidyl-argininyl-chloromethanes with boar acrosin indicated that these compounds as a general group of reagents were highly effective in the inactivation of acrosin since at least half of the reagents tested rapidly inactivated this protease at a concentration of 0.10 micrometer or lower. For example, Dns-Glu-Gly-ArgCH2Cl inactivates acrosin by 50% in 1.8 min at a concentration of 75 nM, whereas in contrast, a 14000-fold higher concentration of Nalpha-tosyllysyl-chloromethane is required to obtain an equivalent rate of inactivation. A comparison of the reactivity of acrosin and trypsin with the peptides of arginyl-chloromethane containing different substituents in the P2 and P3 positions suggests that the secondary binding sites of these two proteases are very similar. Reagents with homoarginine, lysine and D-arginine in the P1 position have also been prepared and evaluated, but these were considerably less effective than the corresponding arginyl-chloromethanes in the inactivation of both acrosin and trypsin.
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PMID:Inactivation of boar acrosin by peptidyl-arginyl-chloromethanes. Comparison of the reactivity of acrosin, trypsin and thrombin. 71 Nov 59

Acidic extracts of washed, ejaculated human spermatozoa contain, besides acrosin, two proteinase inhibitors, a trypsin-chymotrypsin (elastase) inhibitor (HUSI-I) and a trypsin-acrosin inhibitor (HUSI-II). Using the indirect immunofluorescence technique these inhibitors could be localized in the spermatozoa. Ejaculated spermatozoa were treated with monospecific antibodies raised in rabbits against HUSI-I and HUSI-II, respectively, and with fluorescein-labeled IgG from goat directed against the rabbit IgG. If acetone-fixed spermatozoa were used, fluorescence appeared only in a small ring near or at the equatorial segment of the spermatozoa. After prefixation of washed spermatozoa with 0.36% formaldehyde, however, distribution of both inhibitors in the region of the acrosomal caps could clearly be demonstrated. Present results suggest that they are attached at the plasma membrane. Obviously, in the case of human spermatozoa the inhibitors are relatively easily detached together with the membrane so that prefixation is necessary to achieve proper localization.
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PMID:Localization of seminal plasma proteinase inhibitors in human spermatozoa as revealed by the indirect immunofluorescence technique. 79 87

Acrosin, a trypsin-like proteinase, was localized in the acrosome of methanol-fixed bovine spermatoza by the indirect immunofluorescent technique. Anti-acrosin immunoglobulin was obtained from a rabbit immunized with highly purified bovine acrosin. The results of agarose-gel immunnodiffusion analyses indicated that although the antibody was specific for the acrosomal enzyme, it cross-related with ovine acrosin.
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PMID:Immunofluorescent localization of bovine acrosin. 80 78

Two forms of proacrosin have been purified from ejacualted boar spermatozoa. The isolation method utilized benzamidine to inhibit the premeture activation of the zymogen and included pH precipitation, ammonium sulfate fractionation, and sodium chloride precipitation. Further purification was achieved by Sephadex G-200 FILTRATION OF THE PREPARATION AFTER IT WAS TREATED WITH 8 M urea. The overall proacrosin yield was 58% with a specific acitivity of 253 units/mg of protein. The molecular weights of the proacrosins determined by sodium dodecyl sulfate disc gel electrophoresis were 55,000 and 53,000. Proacrosin autoactivation followed the classical S-shaped activation curve and calcium was not required to obtain full activation. Time course activation studies in 0.1 M Tris/HCl, pH 8.4, at 0 degrees were monitored with sodium dodecyl sulfate-disc gel eletrophoresis and anlytical gel electrophoresis with staining techniques for protein and enzymatic activity. Under the conditions used, the zymogens were sequentially degraded to three different active specise of acrosin (alpha, beta, and gamma). The approximate molecualr weights of the acrosins were 49,000, 39,000, and 25,000 for the alpha, beta, and gamma forms, respectively. The autoactivation is concentration-dependent and can be proteolytically stimulated with either alpha- or beta-acrosin and trypsin, indicating the activation of proacrosin can via a bimolecular process.
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PMID:Boar proacrosin. Purification and preliminary activation studies of proacrosin isolated from ejaculated boar sperm. 84 51

Human acrosin was purified to electrophoretically homogeneous forms by acidic extraction of washed ejaculated spermatozoa and gel filtration of the acidic extracts on Sephadex G-75, followed by affinity chromatography on p-amino-benzamidine Sepharose. Human acrosin exists in at least four molecular forms. The apparent molecular weights of three forms were determined to be 64 000, 38 000 and 25 000, respectively. The high molecular weight form is transformed to the low molecular weight forms by incubation of the acrosin preparation obtained from freshly ejaculated spermatozoa in solutions of pH near 7. Like boar acrosin, human acrosin is also a glycoprotein and therefore reversibly bound to Concanavalin A-Sepharose. The amino acid composition of the 25 000 molecular weight form is similar to that of human trypsin. Rabbit anti-boar-acrosin gamma-globulins form a precipitate with human acrosin, but not with porcine trypsin or human plasmin. The relationship between the occurrence of multiple acrosin forms and proenzyme activation by limited proteolysis is discussed.
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PMID:Multiple forms of human acrosin: isolation and properties. 98 58

Human seminal plasma contains two acid-stable proteinase inhibitors, HUSI-II (Mr approximately 6500) and HUSI-I, (Mr approximately 11 000) with different inhibition specificities. The inhibitory activity of HUSI-II is strongly limited to trypsin and acrosin; both enzyme-inhibitor complexes are very stable (e.g. bovine trypsin-HUSI-II complex: Ki = 1 x 10(-10)M; human acrosin-HUSI-II complex: Ki = 2.7 x 10(-10)M). The inhibitor from human seminal plasma HUSI-II may therefore be seen as the natural antagonist of the sperm protease acrosin. In addition to pancreatic trypsin and alpha-chymotrypsin, HUSI-I forms strong complexes with neutral proteases of the lysosome-like granules from human granulocytes, for example, the elastase (Ki = 2.5 x 10(-9)M) and cathepsin G, the chymotrypsin like protease (Ki = 7 x 10(-8)M).
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PMID:Inhibitors of acrosin and granulocyte proteinases from human genital tract secretions. 99 78


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