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:3.4.21.4 (trypsin)
42,187 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

Antibody-mediated spermagglutination is responsible for infertility in some couples and fertilization in vitro can also be impaired by these antibodies. Having previously demonstrated the possibility of enzymatic disagglutination in such situations, the functional potential of disagglutinated spermatozoa has now been assessed. Chymotrypsin (500 U/ml) and papain (50 U/ml) resulted in impairment of oocyte penetration in the zona-free hamster egg penetration test. Trypsin (500 U/ml), while having no effect on egg penetration of normal spermatozoa, significantly improved oocyte penetration of spermatozoa which had been previously incubated with spermagglutinating antibody-positive sera. Sperm-mucus interaction was not improved, however, by trypsin treatment of agglutinated spermatozoa. This technique may be of value in conjunction with in-vitro fertilization in situations where spermagglutination exists, and also possibly with intra-uterine insemination if improved fertilizing ability can be confirmed in vitro.
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PMID:Treatment of spermagglutination with proteolytic enzymes. II. Sperm function after enzymatic disagglutination. 218 63

Buffalo blood serum is a potent source of antisticking factor (ASF) that inhibits with high affinity adhesion of goat epididymal spermatozoa to the glass surface of hemocytometer counting chamber. The serum is also capable of inhibiting glass-sticking of spermatozoa of the buffalo, ram, and bull. The serum ASF activity is nondialyzable and stable to heat treatment at 100 degrees C for two minutes. The activity of the serum ASF was lost completely when treated with trypsin (50 micrograms/ml) at 37 degrees C for thirty minutes indicating the polypeptide nature of the ASF. Serum ASF activity consists of at least two factors (A and B) as shown by concanavalin A-agarose affinity chromatography. ASF-A and -B represent nearly 75% and 25% of the total serum ASF activity. ASF-B is a glycoprotein as it binds with high affinity to concanavalin A. The sera of species such as man, goat, and rat possess ASF activity.
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PMID:Antisticking protein factors in buffalo blood serum. 222 76

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.
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PMID:Chymotrypsin-like enzymes are involved in sperm penetration through the vitelline coat of Ciona intestinalis egg. 222 80

During spermatogenesis, DNA in the sperm head becomes more tightly condensed as histones are replaced by protamine-like molecules. In this article, the question is asked whether, during the production of this highly differentiated cell, controls are imposed on the spatial organization of DNA within the nucleus. Heads from bull spermatozoa were isolated by a technique that removed the plasma membrane and acrosomal contents, and the DNA was induced to decondense by addition of 2-mercaptoethanol and trypsin. Under these conditions, decondensation was induced in all regions of the head. To determine whether there was any spatial restraint on packaging of the genome, three DNA probes were used (pl.709-512, containing an interspersed repetitive sequence; pCSIH, containing a copy of the major bovine centromeric statellite sequence; p18 s and p28 s, containing the 18 S and 28 S ribosomal genes) that might be expected to hybridize to different regions. Results showed that the interspersed repetitive probe hybridized to all regions of the head, whereas the ribosomal and centromeric probes hybridized to sequences that were largely confined to the equatorial region of the sperm. We conclude that organization of the genome in the bovine sperm nucleus is not random.
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PMID:Spatial organization of repetitive DNA sequences in the bovine sperm nucleus. 225 88

The kinetic properties and inhibitor sensitivity of human sperm phospholipase A2 (PLA2; EC 3.1.1.4) were studied. Phospholipase activity was isolated from human spermatozoa by acid extraction. Hydrolysis of dipalmitoyl phosphatidylcholine was specific to the sn-2 position. Activity was sensitive to product inhibition (60% inhibition by 0.1 mM lysophosphatidylcholine). The effects of Ca2+ and sodium deoxycholate on enzyme activity were biphasic; maximal activities were observed at 0.5 mM concentration of each agent. PLA2 was stimulated (135%) by 3% dimethylsulfoxide and was inhibited by elevated ionic strength (approximately 70% inhibition with either 0.2 M NaCl or 0.2 M KCl). Two molecular forms of PLA2 were kinetically distinguishable, one with an apparent Michaelis constant and maximal reaction velocity of 3.0 microM and 0.64 mlU/mg protein and the other with respective constants of 630 microM and 32.0 mlU/mg protein. Both forms of the enzyme were Ca2+ dependent and heat stable; however, the low-Km activity was less resistant to 60 degrees C preincubation at pH 7.5 (28% inactivation of low-Km activity after 45 min, as compared to no effect on high-Km activity). Quinacrine was a noncompetitive PLA2 inhibitor with Kis for low- and high-Km activities of 0.42 mM and 0.49 mM, respectively. Trifluoperazine (calmodulin antagonist) inhibited the high-Km activity noncompetitively (Ki = 87 microM) and the low-Km activity by a mechanism consistent with the removal of a nonessential activator. Dissociation and rate constants for inactivation of low- and high-Km activities by p-bromophenacyl bromide were 0.28 mM and 0.032 min-1, and 0.73 mM and 0.066 min-1, respectively. PLA2 was inhibited by p-nitrophenyl-p'-guanidinobenzoate, at higher concentrations (10(-4)-10(-3) M) than required to inhibit trypsinlike proteinases; p-aminobenzamidine, another potent trypsin/acrosin inhibitor, stimulated (approximately 40%) PLA2 at concentrations from 2-5 mM but inhibited PLA2 (40-50%) at a concentration of 10 mM. MnCl2 (5mM) inhibited low- and high-Km PLA2 activities by 77% and 76%, respectively. Quinacrine (0.4 mM), trifluoperazine (20 microM), p-bromophenacyl bromide (20 microM), and MnCl2 (5 mM) were tested as inhibitors of the ionophore A23187-induced human acrosome reaction. Inhibition was noted only with quinacrine (32%) and MnCl2 (93%). The effect of MnCl2 was restricted to an interaction with A23187, rather than with PLA2; p-Bromophenacyl bromide inhibited (P less than 0.05) PLA2 (29%) when added to intact spermatozoa but had no effect on the acrosome reaction. PLA2 inhibition was poorly correlated with the acrosome reaction.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:Characterization and inhibitor sensitivity of human sperm phospholipase A2: evidence against pivotal involvement of phospholipase A2 in the acrosome reaction. 226 93

Water-extracted proteins from nine geographically diverse strains of Renibacterium salmoninarum, all of which agglutinated rabbit erythrocytes and rainbow trout spermatozoa, were compared by SDS-PAGE. Extracts from eight strains, including the type strain, ATCC 33209, were similar, containing a major protein of 57 kDa and a minor protein of 58 kDa. The SDS-PAGE protein profile of the Char strain did not contain the 58 kDa protein. A non-agglutinating strain, MT-239, which was also non-hydrophobic, did not produce any water-extractable protein. Immunoblot reactions with rabbit antiserum prepared against whole cells of the type strain demonstrated that the water-extracted haemagglutinins from the various strains were antigenically related. When purified by polyacrylamide gel zone electrophoresis, the haemagglutinin from R. salmoninarum ATCC 33209 formed a doublet band with molecular masses of 57 and 58 kDa, similar to the previously described F antigen. The water-extracted haemagglutinin agglutinated salmonid spermatozoa, was degraded by protease K and trypsin, and was shown to self-assemble onto the cell surface.
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PMID:Characterization of the Renibacterium salmoninarum haemagglutinin. 238 Jun 89

Lactate dehydrogenase C4 (LDH-C4) is an antigenic protein that occurs only in spermatozoa and the mature testis. The antibody-combining sites of this enzyme were mapped by measuring the binding of anti-LDH-C4 by isolated peptides. Pure mouse LDH-C4 was digested with trypsin, and the resulting fragments were fractionated by reverse-phase high-pressure liquid chromatography. Rabbit anti-mouse LDH-C4 bound to 13 pure peptides. Amino acid compositions and partial or complete sequencing by the Edman degradation was used to identify eight of these fragments in the complete structure of the molecule. The relationship between structure and antigenicity of these peptides is discussed in detail. These data fit best to the domain model of protein antigenicity. This antigenic map of LDH-C4 will be useful in the design of a synthetic contraceptive vaccine.
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PMID:Antigenic domains of the sperm-specific lactate dehydrogenase C4 isozyme. 241 Jul 78

In a series of experiments the influence of the trypsin inhibitors aprotinin (Trasylol) and TLCK (N-p-tosyl-L-lysin chloromethyl ketone) on the gelatinolytic activity of acrosin and motility of rabbit spermatozoa was tested. Ejaculated, highly motile spermatozoa were washed in Brackett-Medium. 12.5 to 1000 microns Aprotinin and 50 to 1000 micrograms TLCK, respectively, were added to samples of 1 ml sperm suspension: the specimens were incubated at 37 degrees C. Increasing aprotinin concentrations reduced the gelatinolytic activity of acrosin and the sperm incubation at a concentration of 1000 micrograms Aprotinin/ml sperm. Spermatozoa in all TLCK specimens were entirely immotile 1.5 hours after incubation. The gelatinolytic activity of acrosin was obviously not inhibited at any TLCK concentration. These results suggest that, under these experimental conditions, aprotinin and TLCK may impair primarily the motility spermatozoa.
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PMID:[The effect of the trypsin inhibitor aprotinin (Trasylol) and TLCK on the gelatinolytic activity of acrosin and the motility of rabbit sperm in vitro]. 247 24

The endocervical canal is filled with a mucus gel, the properties of which vary during the ovulatory cycle. At mid-cycle the amount of mucus increases, mainly owing to an oestrogen-induced increased hydration of the gel, mucus becomes less visco-elastic and the penetration of the spermatozoa is facilitated. In contrast, under the influence of progesterone during the luteal phase, mucus turns into a less hydrated, highly visco-elastic structure which acts as a barrier to sperm. The mucus gel is formed by very large and structurally complex glycoproteins perfected by evolution to tease and disunite the scientists engaged in unravelling their secrets. The macromolecules are referred to as the mucus glycoproteins or the mucins. Hydrodynamic studies show that cervical mucus glycoproteins (Mr 10-15 x 10(6] behave as random coils, which occupy large spheroidal domains in dilute solution. The predicted 'linear' structure is supported by evidence obtained with electron microscopy. By this technique, the macromolecules are visualized as 'threads' with a skewed and polydisperse distribution of contour lengths (number-average length, 1.5 microns; range 0.5-5 microns). The macromolecules may be cleaved into subunits (Mr 2-3 x 10(6] by reduction of disulphine bonds and these fragments can be divided into large glycopeptides (T-domains; Mr 300,000-400,000) by trypsin. Most of the carbohydrate, which accounts for approximately 80% by weight of the macromolecule and occurs as a heterogeneous population of oligosaccharides, is enriched within the T-domains. The high-Mr glycopeptides thus correspond to long (of the order 100 nm) stretches of protein covered with 100-300 oligosaccharides which protect the core from proteolysis. These regions of the macromolecule are referred to as oligosaccharide 'clusters' and subunits of cervical mucins contain, on average, 3-5 of these 'clusters'. Each 'cluster' is flanked by stretches of protein which are less substituted with carbohydrate and, consequently, more sensitive to proteolysis. There is evidence that these parts of the core, referred to as the 'naked' regins, are folded and stabilized by disulphide bonds. Cervical mucus glycoproteins may thus be viewed as a linear array of oligosaccharide-rich 'clusters' alternating with structures reminiscent of a globular protein. Little is known about how the mucus glycoproteins interact to form the gel. The classical 'Odeblad concept' postulates that the mucins form bundles ('micelles') which are then interconnected in a hormone-dependent way. In contrast, light-scattering studies suggest that cervical mucus is an entangled net-work of long and flexible macromolecules.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:Structure and macromolecular properties of cervical mucus glycoproteins. 270 81


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