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)

A fertilizing sperm of the anuran amphibians has to pass through the jelly envelopes and the vitelline envelope (VE) before making a successful fusion with the egg plasma membrane. Of these the jelly envelopes, secreted by the long pars convoluta (PC) portion of the oviduct, have long been known to be indispensable for the sperm entrance in the egg. The most recent experiments employing dejellied uterine eggs of the toad, Bufo bufo japonicus, revealed that the jelly plays its role in fertilization by its unique capacity of retaining divalent cations (Ca2+ and/or Mg2+) which are essential for a fertilizing sperm. There are other lines of evidence which implicate that the secretions of the uppermost portion of oviduct, p. recta (PR), render the VE penetrable by sperm. We show that the secretory granules (PRG) isolated from PR of ovulating Bufo females by centrifugation in Percoll possess such biological activities as an increase of fertilizability of coelomic eggs and the induction of both the acrosome reaction and a release of the VE lysin from sperm. In addition, the activities of the PRG are inhibited by trypsin inhibitors, and this trypsin-like activity is dependent on Ca2+. These results, combined with the previous immunohistochemical demonstration of the deposition of PR-substance(s) in the VE, lead us to propose that a fertilizing toad sperm is acrosome-reacted in response to the PRG substance deposited in the VE and finds a way of traversing the VE by the released lysin, both of which may be dependent on Ca2+ supplied by jelly envelopes, the product of PC.
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PMID:The role of oviducal secretions in mediating gamete fusion in the toad, Bufo bufo japonicus. 310 79

The sonicated supernatant of the sperm of the toad, Bufo japonicus, can digest easily the vitelline coat (VC) of uterine eggs, and to a lesser extent the VC of coelomic eggs, but not that of activated eggs. The VC lysis and fertilization were competitively inhibited in the presence of t-butyloxycarbonyl-L-Gln-L-Arg-L-Arg-4-methylcoumaryl-7-amide (Boc-Gln-Arg-Arg-MCA), suggesting the involvement of proteases in the fertilization process. Starting from a sonicated supernatant, a potent VC lysin, possessing hydrolytic activity on Boc-Gln-Arg-Arg-MCA, was obtained by anion-exchange chromatography and gel filtration. The activity of the partially purified lysin was inhibited by diisopropyl fluorophosphate (DFP) and by such trypsin inhibitors as soybean trypsin inhibitor, leupeptin, and (p-amidinophenyl) methanesulfonyl fluoride hydrochloride, but not by chymostatin, E-64, and ethylene glycol bis(beta-aminoethyl ether)-N,N,N',N'-tetraacetic acid. The molecular weight of the lysin was estimated to be 32K, based on the fluorographic image of 3H-DFP binding to the lysin on sodium dodecyl sulfate gel electrophoresis. The VC lysin was most active at pH 7.0-7.6 and under low ionic strength equivalent to fresh water. The release of the VC lysin was induced upon incubation of sperm with the contents of oviducal pars recta granules (PRG), which are known to induce the acrosome reaction. We conclude that the protease studied here represents the VC lysin of toad sperm that is involved in fertilization by digesting the VC of uterine eggs, probably released as a result of the acrosome reaction induced by PRG.
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PMID:Classification, inhibition, and specificity studies of the vitelline coat lysin from toad sperm. 323 42

A group A streptococcal strain rich in Fc receptors was selected by an immunoblotting technique and used as the source for isolation of a functionally active Fc receptor. A variety of extraction techniques were compared including (1) heat extraction at neutral, acid or alkaline pH, (2) treatment with the enzymes mutanolysin, hyaluronidase, trypsin, papain or phage lysin, or (3) autoclaving or heating in the presence of sodium dodecyl sulfate. The most homogeneous receptor was recovered following heat extraction and contained two molecular weight forms. The major form had a molecular weight of 56 000 daltons and the minor form had a molecular weight of 38 000 daltons. These two proteins could be isolated without loss of activity by binding to and elution from a column of immobilized human IgG. An antibody prepared against a single form of the affinity purified receptor demonstrated reactivity with both molecular weight forms of the heat extracted receptor. The group A receptor was found to be both antigenically and physicochemically distinct from either the type I receptor found on the majority of Staphylococcus aureus strains or the type III Fc receptors found on the majority of group C streptococcal strains.
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PMID:Isolation and partial characterization of a type II Fc receptor from a group A streptococcus. 352 Feb 93

Spermatozoa of the California red abalone (Haliotis rufescens; Phylum Mollusca, order Archeogastropoda) possess an acrosomal protein that dissolves the egg vitelline layer during fertilization. Evidence strongly suggests that the dissolution mechanism is a stoichiometric, nonenzymatic process that depends on the hydrophobic nature of the sperm protein which should therefore be termed an egg-lysin. Here we report the complete amino acid sequence of this unique protein. Peptides obtained by cyanogen bromide cleavage and trypsin and V8 protease digestions were isolated and subjected to automated Edman degradation. Seven unique CNBr fragments accounted for the intact lysin and the proteolytically derived peptides were used to establish the order of these fragments. The protein is composed of 134 amino acids and contains 36 charged amino acids. The majority of these occur at distances of 2 or 3 residues from each other. A stretch of 41 amino acids contains 10 positively charged amino acids and no negatively charged residue. Model building experiments demonstrated that the charged residues that may occur in alpha-helical regions of the protein would occupy one-half of the circumference of such helices. The other half would display predominantly hydrophobic residues. This arrangement of the charged and hydrophobic residues may account for the biological properties of the lysin.
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PMID:Amino acid sequence of an egg-lysin protein from abalone spermatozoa that solubilizes the vitelline layer. 389 51

The extraction of group A streptococcal antigens by group C phage-associated lysin has been confirmed. In addition to the T antigen the extract contained M-protein, group-specific polysaccharide and mucopeptide antigen which was difficult to remove. This method of extraction of the T antigen was compared with the trypsin method. The latter method was found to be of advantage in giving a pure specific antigen.
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PMID:Studies on two methods for extraction of streptococcal T antigens. 451 45

The sensitivity of Streptococcus faecalis (ATTC 8043) to S. zymogenes X-14 bacteriocin depends greatly on its physiological age. Sensitivity decreases from the mid-log phase on and is completely lost in the stationary phase. The sensitivity of erythrocytes to the hemolytic capacity of the bacteriocin showed considerable species variation. The order of increasing sensitivity was goose < sheep < dog < horse < human < rabbit. However, when red cell stromata were used as inhibitors of hemolysis in a standard system employing rabbit erythrocytes the order of increasing effectiveness was sheep < rabbit < human < horse < goose. When rabbit cells were used in varying concentrations with a constant hemolysin concentration, there was a lag of about 30 min, which for a given hemolysin preparation was constant for all red cell concentrations. Furthermore, the rate of hemolysis increased with increasing red cell concentration. If red cells are held constant and lysin varied, the time to reach half-maximal lysis varies directly with lysin but is not strictly proportional. Bacterial membranes were one to three orders of magnitude more effective than red cell stromata as inhibitors. The order of increasing effectiveness seems to be Escherichia coli < Bacillus megaterium < S. faecalis < Micrococcus lysodeikticus. In addition to membranes, a d-alanine containing glycerol teichoic acid, trypsin in high concentration, and deoxyribonuclease also inhibited hemolysis. Ribonuclease, d-alanine, l-alanine, dl-alanyl-dl-alanine, N-acetyl-d-alanine, N-acetyl-l-alanine did not inhibit hemolysis.
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PMID:Bacteriocin (hemolysin) of Streptococcus zymogenes. 497 10

A cationic protein of rabbit serum bactericidal for Staphylococcus aureus was purified. The specific activity per unit of protein of the purified staphylocidal preparation was approximately 37,000 times greater than that of the serum from which it was isolated. Similar techniques were used to purify serum beta-lysin active against Bacillus subtilis approximately 24,000 times. The staphylocidal activity cannot be attributed to the same beta-lysin active against B. subtilis, lysozyme, or antibody-complement systems. The concentrations of staphylocidal beta-lysin in the sera of the five mammalian species studied did not correlate with their beta-lysin activities against B. subtilis. The two beta-lysins are similar in that both were heat-stable, sensitive to trypsin digestion, had molecular weights near 6,000, and were found in higher concentrations in serum than in plasma. Furthermore, similar techniques can be used to absorb and elute both substances in highly purified forms using cellulose asbestos filter pads and ion exchange chromatography on carboxymethyl cellulose. In contrast to the beta-lysin against B. subtilis, the staphylocidal beta-lysin was not released from blood platelets, and it was inactive in the presence of heparin, sodium citrate, sodium oxalate, ethylenediaminetetraacetic acid, acidic phospholipids, and acid pH values. A variety of proteins, including those of normal serum, preferentially inhibited the bactericidal activity of staphylocidal beta-lysin but not the beta-lysin against B. subtilis.
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PMID:Purification of staphylocidal beta-lysin from rabbit serum. 497 97

T-proteins of Streptococcus pyogenes type 1 were extracted by enzymatic treatment of cells with trypsin, pepsin or C-phage-associated lysin and subsequently purified by ion exchange chromatography on DEAE cellulose as well as by immuno-adsorption on immobilized anti-T-type 1 antibodies. Immunochromatographical purified T1-proteins which were extracted by the different enzymes showed different properties in immuno-electrophoresis, SDS-electrophoresis and amino acid composition although a serological reaction of identity was found in Ouchterlony precipitation. Tryptic and peptic digestion was efficient for extraction of T protein while the extraction with C-phage-associated lysin was unsuitable for isolation of T-protein. The release of T-protein after treatment of cells with this lysin was very low and the preparation purified by this way exhibited cross-reaction with non-absorbed antisera of other types.
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PMID:[T-proteins of Streptococcus pyogenes. III. Communication: purification of T-proteins extracted with trypsin, pepsin and C-phage-associated lysin by means of immunochromatography (author's transl)]. 616 40

We have examined the effects of various mannans, glycoproteins, oligosaccharides, monosaccharides, and sugar phosphates on the binding and phagocytosis of yeast cell walls (zymosan) by mouse peritoneal macrophages. A phosphonomannan (PO(4):mannose ratio = 1:8:6) from kloeckera brevis was the most potent inhibitor tested; it inhibited binding and phagocytosis by 50 percent at concentrations of approximately 3-5 mug/ml and 10 mug/ml, respectively. Removal of the phosphate from this mannan by mild acid and alkaline phosphatase treatment did not appreciably reduce its capacity to inhibit zymosan phagocytosis. The mannan from saccharomyces cerevisiae mutant LB301 inhibits phagocytosis by 50 percent at 0.3 mg/ml, and a neutral exocellular glucomannan from pichia pinus inhibited phagocytosis by 50 percent at 1 mg/ml. Cell wall mannans from wild type S. cervisiae X2180, its mnn2 mutant which contains mannan with predominantly 1(arrow)6- linked mannose residues, yeast exocellular mannans and O-phosphonomannans were less efficient inhibitors requiring concentrations of 1-5 mg/ml to achieve 50 percent reduction in phagocytosis. Horseradish peroxidase, which contains high-mannose type oligosaccharides, was also inhibitory. Mannan is a specific inhibitor of zymosan binding and phagocytosis. The binding and ingestion of zymosan but not of IgG- or complement-coated erythrocytes can be obliterated by plating macrophages on substrates coated with poly-L-lysin (PLL)-mannan. Zymosan uptake was completely abolished by trypsin treatment of the macrophages and reduced by 50-60 percent in the presence of 10 mM EGTA. Pretreatment of the macrophages with chloroquine inhibited zymosan binding and ingestion. These results support the proposal that the macrophage mannose/N-acetylglucosamine receptor (P. Stahl, J.S. Rodman, M.J. Miller, and P.H. Schlesinger, 1978, Proc. Natl. Acad. Sci. U.S.A. 75:1399-1403, mediates the phagocytosis of zymosan particles.
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PMID:Yeast mannans inhibit binding and phagocytosis of zymosan by mouse peritoneal macrophages. 629 48

The synergistic hemolysis of sheep erythrocytes in the CAMP reaction by the sequential action of staphylococcal beta-lysin and the CAMP factor of group B streptococci is the only known function of this extracellular product of group B streptococci. The reaction forms the basis of the CAMP test used to identify group B streptococci because the CAMP factor is believed to be restricted to this group of organisms. However, on occasion other streptococci, notably group A streptococci, may produce a similar synergistic lysis of sheep erythrocytes. The nature of the synergistic lytic factor of group A streptococci responsible for this sequential hemolysis was investigated in a tube CAMP reaction system. The properties of this synergistic lytic factor were found to correspond to those of streptolysin O of group A streptococci. The synergistic lytic factor, like streptolysin O, was produced during the logarithmic phase of growth; the activity was increased by reducing agents and greatly decreased or abolished by heat, trypsin, cholesterol, and anti-streptolysin O, and it was immunogenic in rabbits. This would suggest that the synergistic hemolysis seen in the CAMP reaction system with group A streptococci is due to the action of those small amounts of streptolysin O which remain unoxidized and thus have a capacity to lyse the fragile beta-lysin-treated sheep erythrocytes.
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PMID:Streptococcus pyogenes streptolysin O as a cause of false-positive CAMP reactions. 637 Oct 51


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