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 digestive juice of Achatina balteata, a giant snail of the West African Coast catalyses the hydrolysis of several natural and synthetic compounds. Enzymatic activities on lactose, o- and p-nitrophenyl-beta-D-galactoside, p-nitrophenyl-beta-D-glucoside, p-nitrophenyl-beta-D (and alpha-L-) fucoside, o-nitrophenyl-beta-D-xyloside, p-nitrophenyl-N-acetyl-beta-D-glucosaminide and phenolphthalein-glucuronide have been shown to be present. The effect of pH and substrate concentration on these activities were studied. The galactosidase, glucosidase and fucosidase activities were studied with respect to temperature, heat inactivation, pH stability and incubation with trypsin. Kinetic experiments suggest the presence of several galactosidase activities. This hypothesis is confirmed by specific staining after polyacrylamide gel electrophoresis. These activities showed a broad specificity towards galactosides and glucosides. The digestive juice showed no action on acetyl-L-tyrosine and benzoyl-L-arginine ethyl esters. However a small protease activity was observed on hemoglobine. No lipase activity was found. Sulfatase content was low compared to that of Helix pomatia.
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PMID:[Characterization of some hydrolase activities in digestive juice of Achatina balteata]. 0 61

Mycobacterium ulcerans produces an exotoxin in culture which, when inoculated into guinea pig skin, causes inflammation, necrosis, edema, and other histopathological changes resembling those in infections of humans. The toxin was resistant to heat and to alkalies and was moderately acid labile. Toxic activity was destroyed by Pronase, phospholipase, lipase, amylase, and glucosidase but not by trypsin, collagenase, cellulase, lysozyme, hyaluronidase, or neuraminidase. Toxic activity was resistant to treatment with 2-mercaptoethanol, urea, guanidine hydrochloride, p-chloromercuribenzoate, ethylenediaminetetraacetate, and sodium deoxycholate but was destroyed by sodium m-periodate and sodium dodecyl sulfate. The toxin was precipitated by a wide range of ammonium sulfate concentrations. Extraction with chlorofrom-methanol or petroleum ether destroyed its activity. Isopycnic density gradient ultracentrifugation in KBr produced a high-density lipoprotein layer with a 24-fold increase in specific activity. The results indicate that this toxin is a high-molecular-weight phospholipoprotein-polysaccharide complex.
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PMID:Further characterization of Mycobacterium ulcerans toxin. 3 Jun 94

The zymograms of the digestive caeca and the intestine in seven species of Isopods are established. The glucidasic activities predominate. A relative proteasic poverty is noted as well as the absence of lipases however, the esterases exist. The enzymatic pattern of the gut suggests its participation in the alimentary digestion. The enzymes distribution allows us to establish relations with the food preference of the animals. Some particularities (trypsin, alpha and beta glucosidase) favour a comparison of the marine species with the supralittoral species on one hand and with terrestrial species on the other. This fact does not exclude however the systematic interest of the zymograms.
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PMID:[Comparison of the zymograms of isopod (Crustacea, Peracarides) digestive tubes]. 81 40

The influence of an absorbable glucosidase inhibitor (Bay o 1248) on the endocrine and exocrine rat pancreas was evaluated. Rats fed a standard diet containing Bay o 1248 over 10 days consumed less food, gained about 30% less body weight than controls and showed meteorism. In these animals postprandial plasma insulin and glucose levels were decreased, but the total pancreatic insulin content was not different versus controls. The early insulin secretory response studied by pancreas perfusions was found reduced after a stimulatory glucose load (10 mM). Addition of the glucosidase inhibitor (1 mM) to the incubation medium diminished the glucose-induced insulin release from isolated islets of rats fed a standard diet. The compound added to the perfusion medium (10 microM) induced a slight reduction of half-maximal glucose-induced (10 mM) insulin release from the perfused pancreas. This inhibitory effect disappeared during maximal stimulation (20 mM glucose) of insulin secretion. The compound neither altered basal nor arginine-induced (15 mM) insulin release from the perfused organ. The exocrine pancreas was studied after feeding a Bay o 1248-enriched standard diet over 10 days. Amylase and trypsin concentration and total output into the biliary-pancreatic juice in response to CCK and secretin (20 IU or CU/kg body weight each) were diminished. The pancreatic enzyme content did not differ compared to controls. A significant role of carbohydrate maldigestion, systemic effects of the glucosidase inhibitor, and endocrine-exocrine pancreatic interrelations are discussed to account for the effects of the compound on the rat pancreas.
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PMID:Influence of an absorbable alpha-glucosidase inhibitor (Bay o 1248) on the endocrine and exocrine pancreas of the rat. 243 69

A tumor-derived factor that inhibits cellular DNA synthesis was identified. The factor was extractable from a small-cell lung carcinoma cell line grown in either chemically defined medium or nu/nu mice and inhibited tritiated thymidine ([3H]dThd) incorporation by tumor cell lines of autologous, allogeneic, and xenogeneic origins. The viability of nonproliferating cells from normal tissue was not affected. Tumor extract inhibitory activity was trypsin labile but was resistant to other proteases, neuraminidase, lipase, DNase, RNase, glucosidase, extremes of pH-temperature, and reducing conditions. Inhibitory activity was reversibly bound to helix pomatia lectin but not to lentil, wheat germ, or concanavalin A lectins. Purification by size-exclusion high-performance liquid chromatography yielded a bioactive unimodal 12-kilodalton (kd) peak. The bioactive 12-kd moiety could be eluted from sodium dodecyl sulfate-polyacrylamide gels. Redosing of populations of the T-lymphoblastoid cell line CEM achieved an early (24 hr) sustained depression of pulse [3H]dThd incorporation and ultimately led to decreased population density of factor-treated populations. DNA histogram analysis demonstrated no change in cell cycle phase distribution after factor treatment. 5-Bromo-2'-deoxyuridine (BrdUrd) vs. propidium iodide with the two-parameter Fluorescence-Activated Cell Sorter analysis showed relative inhibition of non-S-phase BrdUrd uptake at 24 hours. A cell-free DNA polymerase assay demonstrated significant inhibition of non-alpha-polymerase-associated DNA synthesis in factor-treated cells. These studies suggest that this tumor-derived inhibitor of DNA synthesis represents a class of cellular products involved in the autoregulation of growth by regulation of DNA synthetic activity.
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PMID:Inhibition of DNA synthesis by a small-cell lung carcinoma-derived protein. 302 Mar 1

The effect of a variety of proteolytic, glycosidic and lipid hydrolyzing enzymes on the ability of mouse egg plasma membrane to interact with sperm was evaluated in this study. Zona-free mouse eggs were exposed to enzymes at various concentrations, washed, and inseminated; the number of sperm attached to or having penetrated the egg plasma membrane was determined at 20 and 180 min post-insemination, respectively. The proteases trypsin and chymotrypsin caused concentration-dependent reductions in both sperm attachment and sperm penetration levels when eggs were incubated at enzyme concentrations ranging from 1- to 1000 micrograms/ml for 30 min prior to insemination. Time-course studies revealed significant inhibition of both sperm attachment and sperm penetration levels after treating zona-free eggs for 5 min at 1000 micrograms/ml of either trypsin or chymotrypsin. Several of the phospholipases tested, including phospholipases C, D, and A2, had no inhibitory effect on sperm penetration levels, with phospholipase C and A2 (100 micrograms/ml) causing inhibition of sperm attachment. Of the glycosidic enzymes evaluated, glucuronidase (1000 micrograms/ml) caused significant inhibition of sperm binding but not sperm penetration, and glucosidase, galactosidase, and neuraminidase had no effect on either sperm attachment or sperm penetration. These findings indicate that the ability of the mouse egg plasma membrane to fuse with sperm can be preferentially altered by treatment with proteases.
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PMID:Enzymatic alteration of the ability of mouse egg plasma membrane to interact with sperm. 306 84

The enzymatic profiles of 109 clinical isolates of Acinetobacter calcoaceticus subsp. anitratus and lwoffi were determined with conventional plate tests and the rapid API ZYM system (Analytab Products, Plainview, N.Y.). The majority of strains tested lacked DNase, hemolysin, protease, elastase and gelatinase. Strong enzymatic activities of butyrate esterase (C4), caprylate esterase (C8) and leucine arylamidase were detected in all isolates. No trypsin, chymotrypsin, alkaline phosphatase or glucosidase activities were present. This profile was characteristic of all isolates examined by the API ZYM system and could serve as a useful diagnostic feature of Acinetobacter calcoaceticus subsp. anitratus and subsp. lwoffi.
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PMID:Enzymatic profile of clinical isolates of Acinetobacter calcoaceticus. 400 64

Transfection is a technique for inducing transformation of normal fibroblasts (NIH 3T3) with DNA (oncogenes) from human tumors. Our goal was to determine if these transformed cells expressed antigens associated with malignancy. NIH 3T3 cells were transfected with DNA fragments from a human acute lymphocytic leukemia (ALL 1-69), and transformed colonies were selected for growth in soft agar. Transfected cells containing human DNA sequences demonstrated by Southern blot analysis were used to immunize Balb/C mice. Monoclonal antibodies were produced and screened for binding to the parental leukemia (ALL 1-69), transfectant (17(2], and 3T3 cells in an enzyme-linked assay. A monoclonal antibody (IgM kappa) designated 17-9H3 bound to ALL 1-69 and secondary transfectant 17(2) but not to NIH 3T3 plasma membranes. Immunoperoxidase staining confirmed this binding pattern and demonstrated that the antigen was expressed on the cell surface. Expression of the antigen by transfectants directly correlated with the presence of a single 6.1 kilobase human DNA sequence. The antibody binding site of the antigen was inactivated by trypsin, glucosidase, and hyaluronidase. Binding of the 17-9H3 antibody was selective for acute lymphocytic leukemias (5/8) and osteogenic sarcomas (33/36), although other tumor types did demonstrate significant binding by immunoperoxidase staining. The majority of normal tissues did not bind 17-9H3 with the exception of some metabolically active cells (renal tubular epithelium, secretory epithelial cells, and cardiac smooth muscle), germ cells, Leydig cells of the testes, and some lymphoid cells. Monoclonal antibodies to oncogene-associated antigens may be potentially useful for cancer diagnosis and therapy and as probes for oncogene isolation.
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PMID:A novel approach to production of antitumor monoclonal antibodies: antibody to a cell surface glycoprotein associated with transformation by a human oncogene. 637 59

Glucosidase I initiates the processing of the oligosaccharide, Glc3Man9GlcNAc2, in newly assembled glycoproteins by excising the distal alpha 1,2-linked glucosyl residue in the oligosaccharide. Earlier, the enzyme purified from the ER of rat and bovine mammary gland has been found to have M(r) of 85 kDa, as examined by SDS-PAGE along with a domain structure in which a 39 kDa lumenally-oriented region is anchored to the ER through a transmembrane segment and a short cytoplasmic tail. These studies were further extended to include the enzyme from several different tissues of the rat, mouse, guinea pig and bovine mammary glands, sheep liver and pig kidney. Using anti-rat glucosidase I antibody as a probe and several biochemical parameters such as SDS-PAGE analysis, trypsin-catalyzed digestion, ConA-binding, endo H susceptibility and peptide mapping analysis by cleavage of the tryptophanyl peptide linkages within the enzyme, it was found that glucosidase I in all of the tissue sources examined has an M(r) of 85 kDa and is cross-reactive to anti-rat glucosidase antibody. The enzyme is a high mannose glycoprotein, and has domain features in its structure; the enzyme from mouse, rat, guinea pig and bovine mammary glands and sheep liver is sequentially cleaved by trypsin to generate fragments of 69, 55 and 39 kDa. The rate of release of the different fragments differs for different sources, indicating some evolutionary changes in its primary structure. The trypsin-released fragments from pig kidney enzyme are 69, 45 and 29 kDa in size, identical to the same observed earlier for pig liver.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Conserved structural features in glycoprotein processing glucosidase I from several tissues and species. 800 15

In the current model for Glc3Man9GlcNAc2-P-P-Dol assembly, Man5GlcNAc2-P-P-Dol, Man-P-Dol, and Glc-P-Dol are synthesized on the cytoplasmic face of the ER and diffuse transversely to the lumenal leaflet where the synthesis of the lipid-bound precursor oligosaccharide is completed. To establish the topological sites of Glc-P-Dol synthesis and the lipid-mediated glucosyltransfer reactions involved in Glc3Man9GlcNAc2-P-P-Dol synthesis in ER vesicles from pig brain, the trypsin-sensitivity of Glc-P-Dol synthase activity and the Glc-P-Dol:Glc0-2Man9GlcNAc2-P-P-Dol glucosyltransferases (GlcTases) was examined in sealed microsomal vesicles. Since ER vesicles from brain do not contain glucose 6-phosphate (Glc 6-P) phosphatase activity, the latency of the lumenally oriented, processing glucosidase I/II activities was used to assess the intactness of the vesicle preparations. Comparative enzymatic studies with sealed ER vesicles from brain and kidney, a tissue that contains Glc 6-P phosphatase, demonstrate the reliability of using the processing glucosidase activities as latency markers for topological studies with microsomal vesicles from non-gluconeogenic tissues lacking Glc 6-P phosphatase. The results obtained from the trypsin-sensitivity assays with sealed microsomal vesicles from brain are consistent with a topological model in which Glc-P-Dol is synthesized on the cytoplasmic face of the ER, and subsequently utilized by the three Glc-P-Dol-mediated GlcTases after "flip-flopping" to the lumenal monolayer.
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PMID:Topological studies on the enzymes catalyzing the biosynthesis of Glc-P-dolichol and the triglucosyl cap of Glc3Man9GlcNAc2-P-P-dolichol in microsomal vesicles from pig brain: use of the processing glucosidases I/II as latency markers. 985 42


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