Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0272170 (SDS)
 50,377 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A chymotrypsin-like enzyme (CTLE) was isolated from the digestive tract of the African migratory locust Locusta migratoria migratorioides by ion-exchange chromatography on diethylaminoethyl (DEAE) cellulose followed by affinity chromatography on phenylbutylamine (PBA) Sepharose. The purity and homogeneity of CTLE have been shown by SDS-PAGE and on cellulose acetate strips. The enzyme has a molecular weight of 24,000, determined by SDS-PAGE and on a Sephadex G-75 calibrated column. It has an isoelectric point of 10.1 and contains 0-1 half cystine residues. Sequence analysis of the first 20 N-terminal amino acids has shown 25% homology with bovine chymotrypsin and 40% homology with Vespa crabo and Vespa orientalis chymotrypsins and with Hypoderma lineatum trypsin. The optimal pH for enzyme activity and stability was in the range of 8.5-9.0. The Km and kcat values, determined on substrates for proteolytic, esterolytic and amidolytic activity, similar to those for bovine chymotrypsin. CTLE was inactivated by PMSF and TPCK indicating the involvement of serine and histidine in its active site. The enzyme was fully inhibited by the proteinaceous, double-headed, chymotrypsin-trypsin inhibitors BBI from soybeans and CI from chickpeas, by chicken ovomucoid (COM) and turkey ovomucoid (TOM), as well as by the Kunitz soybean trypsin inhibitor (STI) which hardly inhibits bovine chymotrypsin. Inhibition studies of CTLE with amino acid and peptide-chloromethylketones point towards the existence of an extended binding site.
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PMID:Purification and characterization of Locusta migratoria chymotrypsin. 324 83

An inhibitor of factor XIIa has been purified from bovine plasma and characterized (Thornton, R.D. and Kirby, E.P. (1987) J. Biol. Chem. 262, 12714-12721). This inhibitor interacts with XIIa to form a very stable complex with a 1:1 stoichiometry. The active site of XIIa, located on the light chain, is directly involved in the interaction, and complex formation between factor XIIa inhibitor and XIIa can be blocked by diisopropyl fluorophosphate, corn trypsin inhibitor, or the chromogenic substrate S2302. Incubation of the complex with excess XIIa does not result in cleavage of the complex. The complex does not spontaneously dissociate and is stable to boiling, SDS, thiocyanate, acid, and hydroxylamine or Tris at pH 7-10. In addition to complex formation, a cleaved form of factor XIIa inhibitor can be observed. We suggest that the inhibitor is acting as a mechanism-based inactivator, using the criteria of time-dependent inactivation under pseudo-first-order conditions, 1:1 stoichiometry, active site involvement, kinetic protection by substrate or by an active site inhibitor, and partitioning between cleavage of factor XIIa inhibitor and inactivation by complex formation.
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PMID:Interaction of bovine factor XIIa with an inhibitor from bovine plasma. 325 42

Venom samples of Russell's viper (Vipera russelli) from three localities in India were analysed for their composition and toxicity. Column chromatographic fractionation on CM-Sephadex C-25 showed the absence of three fractions in the venom samples of southern India compared with the samples from northern and western India. The SDS-PAGE pattern of southern Indian venom samples also showed lack of three protein bands corresponding to molecular weights of 66,000, 39,000 and 9000. Venom samples from northern and western India possessed high acidic phospholipase activity while acidic phospholipase activity was absent in the samples from southern India, which in contrast showed large basic fractions with phospholipase activity. Proteolytic activity was present in all the venom samples; however, this activity, as well as trypsin inhibitor activity, was very low in the southern Indian samples. The ratio of proteolytic activity to inhibitor activity remained constant in most of the venom samples studied. LD50 values for most of the venom samples from northern and western India were twice as high as that of the samples from southern India. High phospholipase activity correlated with high lethal potency in the venom samples studied.
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PMID:Geographical variation in India in the composition and lethal potency of Russell's viper (Vipera russelli) venom. 329 65

A proteinase from the venom of Vipera lebetina was purified by chromatography on Sephadex G-100 and CM-cellulose. The purified proteinase was homogeneous on SDS-polyacrylamide gel electrophoresis and consisted of a single chain with molecular weight of 37,000 +/- 1500. The isoelectric point of the proteinase was over 10. The enzyme was active on casein but not on esters and amides of arginine. It split the oxidized insulin B-chain at the peptide bonds of Tyr16-Leu17, Phe24-Phe25 and Phe25-Tyr26, and glucagon at the bonds Tyr10-Ser11, Leu14-Asp15 and Leu26-Met27. The enzyme was inhibited by DFP and PMSF, and partially by soybean trypsin inhibitor, but not with EDTA.
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PMID:Purification and properties of a proteinase from Vipera lebetina (snake) venom. 330 28

Cathepsin B was purified from rabbit skeletal muscle by ammonium sulfate fractionation and successive chromatographies on Sephadex G-75, phosphocellulose, peptide-conjugated Sepharose, DEAE-Toyopearl and Sephadex G-100. The purified enzyme gave a single protein band on SDS/polyacrylamide gel electrophoresis. The enzyme did not abolish the Ca sensitivity of the ATPase activity of myofibrils. The molecular mass of the enzyme was found to be 27 kDa on gel filtration and SDS/polyacrylamide gel electrophoresis. The optimum pH for the hydrolysis of N alpha-benzoyl-DL-arginine-beta-naphthylamide was 6.5. The enzyme was stable in the range of pH 4.5-5.5. Tetrathionate reacted with thiol groups of the enzyme reversibly so that it stabilized the enzyme. The enzyme was strongly inhibited by iodoacetate, HgCl2, antipain, leupeptin, N alpha-p-tosyl-L-lysine chloromethane and L-tosylphenylalanylchloromethane, but not by pepstatin or trypsin inhibitor.
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PMID:Purification and some properties of cathepsin B from rabbit skeletal muscle. 333 70

The present studies were undertaken to characterize a serine protease released by N-formyl-L-Met-L-Leu-L-Phe (fMet-Leu-Phe)-stimulated neutrophils that rapidly induces platelet calcium mobilization, secretion and aggregation. The biological activity associated with this protease was unaffected by leupeptin, was only weakly diminished by N-p-tosyl-L-Lys-chloromethane, but was strongly inhibited by alpha 1-antitrypsin, soyabean trypsin inhibitor, N-tosyl-L-Phe-chloromethane and benzoyloxycarbonyl-Gly-Leu-Phe-chloromethane (Z-Gly-Leu-PheCH2Cl). These observations indicated that the biological activity of neutrophil supernatants could be attributed to a chymotrypsin-like enzyme such as cathepsin G. Furthermore, platelet aggregation and 5-hydroxytryptamine release induced by cell-free supernatants from fMet-Leu-Phe-stimulated neutrophils were found to be blocked by antiserum to cathepsin G in a concentration-dependent manner but were unaffected by antiserum to elastase. The biological activity present in neutrophil supernatants co-purified with enzymic activity for cathepsin G during sequential Aprotinin-Sepharose affinity chromatography and carboxymethyl-Sephadex chromatography. SDS/polyacrylamide-gel electrophoresis of the reduced, purified protein, demonstrated three polypeptides with apparent Mr values of 31,500, 29,000 and 28,000 and four polypeptides were resolved on acid-gel electrophoresis. Purified cathepsin G from neutrophils cross-reacted with anti-(cathepsin G) serum in a double immunodiffusion assay and elicited platelet calcium mobilization, 5-hydroxytryptamine secretion and aggregation. Calcium mobilization and secretion induced by low concentrations of cathepsin G were partially dependent on arachidonic acid metabolites and ADP, while stimulation by higher enzyme concentrations was independent of amplification pathways, indicating that cathepsin G is a strong platelet agonist. These results suggest that pathological processes which stimulate neutrophils and release cathepsin G can in turn result in the recruitment and activation of platelets.
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PMID:Cathepsin G is a strong platelet agonist released by neutrophils. 339 Jan 56

Three intracellular proteinases termed A, B and C were purified to homogeneity from the unicellular form of the yeast Candida albicans. Enzyme A is an aspartic proteinase that acts on a variety of proteins. Its optimal pH is around 5 and it is displaced to 6.5 by KSCN. It is not significantly inhibited by PMSF, TLCK (Tos-Lys-CHCl2) or soybean trypsin inhibitor but it is inhibited by pepstatin. Its molecular weight is 60 000. Enzyme B is a dipeptidase that acts on esters or on dipeptides without blocks in either the carboxyl or amino ends. Its pH optimum is around 7.5 and the molecular weight is 57 000. It is inhibited by PMSF, TLCK and DANME (N2Ac-Nle-OMe). Proteinase C is an aminopeptidase with an optimum pH around 8. Its molecular weight was 67 000 when determined by SDS gel electrophoresis and 243 000 when determined by gel weight was 67 000 when determined by SDS gel electrophoresis and 243 000 when determined by gel filtration. It is active towards dipeptides in which at least one amino acid is apolar and is not active when the N-terminal amino acid is blocked. It is inhibited by EDTA or o-phenanthroline and activated by several divalent cations.
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PMID:Purification and properties of three intracellular proteinases from Candida albicans. 351 44

The thiol protease was purified from adult Paragonimus ohirai by alpha 1-antitrypsin-Sepharose, Sephadex G-75 and CM-cellulose, measuring its activities to hydrolyze hemoglobin and tosyl-L-lysine alpha-naphthyl-ester. The purified protease showed a single band on polyacrylamide disc gel isoelectrophoresis as zymogram with Tos-Lys-NE and also by protein staining, and its pI was found to be 6.4. The molecular weight was calculated to be 29,000 by gel filtration and 27,000 by SDS-polyacrylamide gel electrophoresis as a single polypeptide. The protease hydrolyzed hemoglobin and Tos-Lys-NE optimally at pH 4.0 and 5.0, respectively. The both hydrolyzing activities were inhibited by alpha 1-AT and soybean trypsin inhibitor as well as thiol protease inhibitors such as antipain, E-64 and p-hydroxymercuriphenylsulfonate. These results indicate that this enzyme is a new type thiol protease.
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PMID:Purification and properties of a thiol protease from lung fluke adult Paragonimus ohirai. 351 8

A collagenolytic enzyme was purified to homogeneity from the activated pancreatic extract of the catfish Parasilurus asotus by chromatography on DEAE-cellulose, hydroxylapatite, and Cellulofine columns. The molecular weight of the enzyme was estimated to be 29,500 by SDS-polyacrylamide gel electrophoresis. The enzyme is capable of degrading native, reconstituted calf skin collagen fibrils at pH 7.5 and 37 degrees C, and also of reducing the viscosity of native calf skin collagen at pH 7.5 and 20 degrees C. The SDS-polyacrylamide gel electrophoresis of thermally denatured enzyme-collagen reaction mixtures showed that the enzyme can cleave peptide bonds in the non-helical and triple-helical regions of the collagen. The enzyme was inhibited by DFP, PMSF, soybean trypsin inhibitor, and chicken ovoinhibitor, but not by metal-chelating reagents EDTA, EGTA, o-phenanthroline, or L-cysteine. These results indicate that the enzyme is a unique collagenolytic proteinase belonging to the group of serine proteinases and is a new member of the class of pancreatic enzymes.
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PMID:Purification and characterization of a collagenolytic serine proteinase from the catfish pancreas. 351 83

Concanavalin A, a specific glycoprotein probe, was optimally labelled to a maximum stoichiometry of 0.4 mol of chlorotriazinylaminofluorescein (CTAF)/mol of concanavalin A monomer under mild reaction conditions (pH 8.0, 6 h), and under these conditions the CTAF concanavalin A preparation retains its carbohydrate-binding ability and is able to penetrate SDS/7.5-15%-polyacrylamide gradient gels. CTAF-concanavalin A gives fluorescent bands for the glycoproteins transferrin, fetuin and deoxyribonuclease and shows no fluorescent response for the non-glycoproteins bovine serum albumin and soya-bean trypsin inhibitor. The detection limit of sensitivity for CTAF-concanavalin A, which is similar to that of fluorescein isothiocyanate-concanavalin A, is in the range 5-25 micrograms of glycoprotein. CTAF-concanavalin A is a suitable probe for the detection of glycoproteins in higher-percentage (greater than or equal to 10%) SDS/polyacrylamide gels, and will probably have other applications in, for example, fluorescent energy transfer and other structure-function studies.
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PMID:The synthesis of fluorescent chlorotriazinylaminofluorescein-concanavalin A and its use as a glycoprotein stain on sodium dodecyl sulphate/polyacrylamide gels. 363 34


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