Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound   Target Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound

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Query: EC:3.4.21.1 (chymotrypsin)
10,938 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The treatment of antibody-mediated spermagglutination by corticosteroid therapy has a high incidence of side-effects and sperm washing is often followed by re-agglutination. The possibility of enzymatic disagglutination was therefore investigated. In the first part of the study the effects of four proteases on sperm motility, vitality and longevity were evaluated. Subtilisin had prohibitively detrimental effects even at 10 U/ml. However, chymotrypsin (less than or equal to 500 U/ml), trypsin (less than or equal to 500 U/ml) and papain (less than or equal to 50 U/ml) had no adverse effects. In the second series of experiments one or more of these latter three enzymes was found to disagglutinate spermatozoa which had previously been incubated with sperm-agglutinating antibody-positive sera in 87% of cases. Although further investigation is required, enzymatic disagglutination may be beneficial for the treatment of immunologically mediated spermagglutination.
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PMID:Treatment of spermagglutination with proteolytic enzymes. I. Sperm motility, vitality, longevity and successful disagglutination. 218 62

Goat epididymal intact spermatozoa have been shown to possess on the external surface specific receptors that bind with high affinity to exogenous [8-3H]cyclic AMP. The ecto-cyclic AMP-receptor activity was not due to contamination of broken or "leaky" cells, if any. The binding reaction of [3H]cyclic AMP with the receptors was extremely rapid. Uptake of the labeled cyclic AMP to the sperm cytosolic fraction was undetectable. There was little leakage of cyclic AMP-receptors from intact spermatozoa during the binding assays. The binding reaction was proportional to cell concentration, specific and saturable at 250 nM cyclic AMP. The binding of the labelled cyclic nucleotide was nearly completely displaced at saturating concentrations (2.5 microM) of the unlabelled nucleotide. The ecto-receptors showed high specificity for binding to cyclic AMP. The Kd of the binding sites was approximately 1.7 X 10(-8) M. The binding interaction was highly sensitive to treatment with proteolytic enzymes: trypsin, chymotrypsin, or pronase (125 micrograms/ml). Sonication caused a nearly 450% increase of the ecto-receptor activity. The specific activity of the ecto-cyclic AMP-receptor was approximately twofold higher in the vigorously forwardly motile spermatozoa than in the "composite" cells, suggesting that the ecto-receptors may have a role in modulating flagellar motility.
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PMID:Ecto-cyclic AMP-receptor in goat epididymal intact spermatozoa and its change in activity during forward motility. 282 7

Using immunoaffinity chromatography on a Sepharose 4B column with adsorbed antibodies to the basic inhibitor in bovine organs (Kunitz-type), a proteinase inhibitor was isolated from boar seminal vesicle fluid. The isolated protein inhibited acrosin, trypsin, plasmin and chymotrypsin, but not kallikrein. Its molecular weight determined by gel filtration on Sephadex G-50 was 9,500 (+/- 500) and by SDS electrophoresis in polyacrylamide gel 12,000 (+/- 500) daltons. The protein was demonstrated by immunoprecipitation only in boar seminal vesicle fluid and seminal plasma, and by indirect immunofluorescence on ejaculated spermatozoa and in the epithelium of boar seminal vesicles. This inhibitor is the first acrosin inhibitor specific for the genital organs, which evidently belongs to the group of Kunitz type inhibitors, to be described.
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PMID:A Kunitz type of proteinase inhibitor isolated from boar seminal vesicle fluid. 293 36

Ram spermatozoa adenylate cyclase is insensitive to all usual regulatory processes. The purification of its active catalytic subunit was accomplished after proteolytic solubilization of a particulate fraction by alpha-chymotrypsin. The purification (26,000-fold from the particulate fraction or 125,000-fold from the whole-sperm proteins) was achieved by conventional procedures (DEAE-Trisacryl, Ultrogel AcA 34, DEAE-Sephacel, hydroxyapatite), in the absence of detergent, and with a yield of 5-10% and a final specific activity of 19 mumol cyclic AMP formed mg protein-1 min-1 at 30 degrees C in the presence of manganese as cosubstrate. The solubilized enzyme, stable at the beginning of the purification procedure, became unstable at the later stages. After the last step (chromatography on hydroxyapatite) half-lives of 27 min, 50 min and 160 min were obtained at 30 degrees C, 20 degrees C and 4 degrees C respectively. The enzyme was stabilized by addition of bovine serum albumin and Lubrol PX, 80% of the activity remaining after 24 h at 4 degrees C. The purified enzyme exhibited a Km value similar to that of the native enzyme (Km = 1.4 mM). Unlike the native enzyme, the purified enzyme has an absolute requirement for MnATP; no significant activity was recovered in the presence of MgATP. Adenosine inhibited the activity of both the native and purified forms of the enzyme to the same extent and in a non-competitive manner. This indicates that adenosine acts on the catalytic component itself and the inhibition site and the catalytic site are different. Data obtained with adenosine analogs indicate that adenosine interacts with the cyclase catalytic subunit with a 'P-site' specificity. The purified adenylate cyclase, which had an apparent molecular mass of 38 kDa on a high-performance liquid chromatography column [Stengel, D., Guenet, L. and Hanoune, J. (1982) J. Biol. Chem. 257, 10,818-10,826], gave a doublet of 36 kDa and 34 kDa on sodium dodecyl sulfate gel electrophoresis. This represents the smallest protein entity associated with adenylate cyclase activity so far reported.
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PMID:Purification of the proteolytically solubilized, active catalytic subunit of adenylate cyclase from ram sperm. Inhibition by adenosine. 302 85

Mouse oocytes matured in vitro in chemically defined medium were not penetrated by spermatozoa. The time required for dissolution of the zona pellucida of such oocytes by alpha-chymotrypsin was much longer than that for ovulated oocytes. Addition of fetal calf serum to the medium for maturation of oocytes improved the incidence of sperm penetration and shortened the time of enzymic dissolution of the zona pellucida. These results suggest that the low rate of fertilization of oocytes matured in vitro is mainly due to qualitative changes of the zona pellucida, which could be overcome by a factor or factors in fetal calf serum.
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PMID:Beneficial effect of serum on the fertilizability of mouse oocytes matured in vitro. 357 87

A new anionic acrosin inhibitor was found in an acidic extract of boar spermatozoa. The protein was purified by hydrophobic and ion exchange chromatography. According to gel filtration and SDS-electrophoresis the inhibitor preparation shows a molecular mass of Mr approximately 6000-7000 daltons. The isoelectric point is close to pH 4.5. It is an effective inhibitor of boar acrosin and bovine trypsin, but it does not inhibit porcine plasmin and pancreatic kallikrein or bovine chymotrypsin. An inhibitor with identical properties was found in high concentration (97% of the total acrosin inhibiting activity) in the fluid of cauda epididymis and also as a minor acrosin inhibiting component (2% of total acrosin inhibiting activity) in seminal plasma. The results indicate that binding of the inhibitor to spermatozoa may have taken place in the epididymis.
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PMID:Demonstration of an anionic acrosin inhibitor in spermatozoa epididymal fluid and seminal plasma of the boar. 390 26

A heat-labile, non-dialyzable factor(s) in soluble fractions from porcine, bull, rabbit and cock spermatozoa was found to incorporate the radioactivity of [14C]isoleucine into a 95 degrees C CCl3COOH-insoluble fraction. The incorporation required ATP, Mg2+, casein and 2-mercaptoethanol. Trypsin and alpha-chymotrypsin inhibited the incorporation, while RNase A and DNase I did not. A mixture of 19 amino acids other than isoleucine had no effect on the incorporation. The reaction product was identified as protein. The incorporated moiety was the isoleucyl moiety of isoleucine and it retained a free alpha-amino group in the product protein. Some other characteristics of this incorporation are also described.
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PMID:Incorporation of isoleucine into protein by a soluble fraction from spermatozoa. 398 5

The flagellar complex of the unusual motile spermatozoon of the fungus gnat, Rhynchosciara sp, does not conform to the usual "9 + 2" filament pattern but rather consists of over 350 pairs of filaments (doublet microtubules) distributed in a spiral array. Experiments were designed to disrupt and extract flagellar microtubular components from spermatozoa of the fungus gnat. Pepsin, chymotrypsin, potassium iodide, urea, and heat were used to extract specific portions of microtubule walls Such experiments provide information on the composition of the wall and the existence of wall sites selectively sensitive to various treatments Results obtained include: (a) doublet microtubules are comprised at least in part of protein, and all subunits are probably not identical; (b) a portion of the B subfiber is apparently more sensitive to disruption than other portions of the doublet microtubule; and (c) the ac cessory singlet microtubules may be chemically different from the doublet microtubules
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PMID:Electron microscope studies of spermatozoa of Rhynchosciara Sp. I. Disruption of microtubules by various treatments. 504 61

1. A method is described for the purification of a proteinase, present in human seminal plasma and previously shown to accelerate migration of spermatozoa through cervical mucus in vitro. A 25-fold purification was achieved in three steps, consisting of ammonium sulphate fractionation, chromatography on CM-cellulose and gel filtration. 2. The enzyme displays some properties similar to chymotrypsin: pH optimum 7.5-8.0; substrate preference of casein, haemoglobin and benzoyltyrosine ethyl ester but not benzoylarginine ethyl ester; mol.wt. 33000. However, it is unaffected by 1mm-di-isopropyl phosphofluoridate or 1mm metal cations, and in this respect differs from chymotrypsin. 3. The properties of the enzyme strongly resemble those of the ;chymotrypsin-like' enzyme discovered in seminal plasma by Lundquist et al. (1955). 4. The use of dimethyl-casein permitted the performance of enzyme assays at substrate concentrations five times higher (up to 50mg/ml) than could be achieved with ordinary casein (10mg/ml).
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PMID:Purification and properties of a human seminal proteinase. 507 26

A proacrosin conversion inhibitor present in boar spermatozoa has been purified and initially characterized. Purification methods included sequential acid extractions of washed spermatozoa at pH 4.0, pH 3.5, and pH 2.5 followed by successive gel filtrations of the pH 2.5 sperm extract supernatant over Sephadex G-75 and G-50. The resulting 8.8-fold purified materials were judged to be homogeneous by sodium dodecyl sulfate-polyacrylamide disc gel electrophoresis, had an estimated molecular weight of 12,800, and a constant specific activity of 65 units/mg. Treatment with the proteinases acrosin, trypsin, or chymotrypsin destroyed the highly purified proacrosin conversion inhibitor, indicating that it is a protein. Additional properties of the inhibitor included stability to long periods of storage at pH 3.0 and 4 degrees C, stability to boiling and lyophilization, and an absolute requirement for divalent cations to maintain activity. The highly purified proacrosin conversion inhibitor does not inhibit acrosin. Therefore, it apparently acts to prevent proacrosin conversion by selectively inhibiting the zymogen's self-catalyzed conversion mechanism.
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PMID:Proacrosin conversion inhibitor. Purification and initial characterization of a boar sperm protein which prevents the conversion of proacrosin into acrosin. 680 Oct 40


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