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)

Two endopeptidases displaying similar specificities towards peptide hormone substrates but differing in molecular size have been identified in rabbit heart and isolated by a combination of ion-exchange chromatography, gel filtration and preparative gel electrophoresis. These two enzymes share several properties with the previously described rabbit brain endooligopeptidase A. They were shown to produce, by a single peptide bond cleavage, [Met5] enkephalin and [Leu5]enkephalin from small enkephalin containing peptides. They also hydrolyze the Phe5-Ser5 bond of bradykinin and the Arg8-Arg9 bond of neurotensin. Characteristically, the activity of both low and high Mr enzymes is restricted to oligopeptides. Both forms of heart endooligopeptidase A are inhibited by antibodies raised against the brain enzyme. When electrophoresed in SDS-polyacrylamide gel under denaturing conditions, the low Mr heart enzyme shows a major band of Mr = 73,000, comparable in size to the brain enzyme. The SDS-PAGE of the high and low Mr enzymes analyzed by immunoblotting with an antibody raised against low Mr brain endooligopeptidase A, showed a major antigen band corresponding to Mr = 72,000. In addition, immunoblotting has also demonstrated that a monoclonal antibody antitubulin reacts with a polypeptide corresponding to Mr = 50,000 present in the purified high Mr endooligopeptidase A. Both enzymes are activated by dithiothreitol and inhibited by thiol reagents, but are not affected by leupeptin, DFP or EDTA, thus indicating that they should be classified as nonlysosomal cysteinyl-endooligopeptidase A.
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PMID:Endooligopeptidase A activity in rabbit heart: generation of enkephalin from enkephalin containing peptides. 324 63

Human peripheral blood mononuclear cells, activated for 14 to 20 days with 1000 U/ml rIL-2, develop strong cytotoxicity for NK sensitive and resistant targets. This process is accompanied by the acquisition of cytoplasmic granules in approximately 60% of the cells and by the expression of esterase activity cleaving the synthetic substrate BLT. The esterase activity, localized in the cytoplasmic granules, was purified and characterized. Three proteins with 3H-DFP binding activity were isolated and had the following properties. Following the proposed nomenclature by Masson et al., the esterases were named human granzymes 1, 2, and 3. Human granzyme 1 on SDS-PAGE has an unreduced relative m.w. of 43,000 and can form disulfide-linked oligomers of relative higher m.w. All forms of granzyme 1 bind 3H-DFP. Upon reduction, granzyme 1 migrates with Mr 30,000 on SDS-PAGE. Additional proteolytic fragments of Mr 24,000 and Mr 28,000 are observed in some reduced preparations. Granzyme 1 cleaves the substrate BLT and appears homologous with murine granzyme A. Human granzyme 2 has an unreduced relative m.w. of 30,000; after reduction, it migrates at Mr 32,000. Even though granzyme 2 binds 3H-DFT, it does not cleave BLT. Human granzyme 2 has properties similar to those of murine granzymes B-H. Human granzyme 3 has unreduced and reduced relative m.w. of 25,000 and 28,000, respectively. It is active in cleaving the substrate BLT. A murine analog for human granzyme 3 has not been described previously. N-terminal sequencing of the purified human granzymes revealed that human granzyme 1 is the gene product of human Hanuka factor cDNA clone and that it represents the human homolog to murine granzyme A. Similarly, human granzyme 2 revealed absolute identity with cDNA-derived N-terminal sequence of a putative human lymphocyte protease cDNA clone.
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PMID:Characterization of three serine esterases isolated from human IL-2 activated killer cells. 326 82

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

1. Beta-fibrinogenase was isolated from the venom of Agkistrodon p. piscivorus by column chromatography on Sephadex G-100, DEAE-Sephacel and by chromatofocusing, with a yield of 2.5 mg of purified enzyme from 1 g of crude venom. 2. The enzyme was homogeneous by SDS and non-SDS disc electrophoresis on polyacrylamide gel at pH 8.3. 3. Beta-fibrinogenase is a glycoprotein possessing both TAME hydrolase and kinin-releasing activities. 4. A mol. wt of approximately 33,500 and an isoelectric point 4.5 was determined. 5. The enzyme is stable to heat treatment and to a pH range of 2-10. 6. Beta-fibrinogenase activity is inactivated by DFP, suggesting that serine is involved in the enzymatic activity. 7. The Michaelis constant (Km) of this enzyme for TAME and inhibition constant (Ki) for DFP were found to be 7.04 X 10(-3) and 4.13 X 10(-3) M, respectively.
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PMID:Beta-fibrinogenase from the venom of Agkistrodon p. piscivorus. 335 57

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

The thiol-dependent serine proteinase (inhibited by DFP, PMSF, pCMB and iodoacetate) was isolated from the whole krill specimens and from the content of the krill digestive tract. The enzyme was purified to homogeneity using a seven-step procedure. Its specific activity with denatured haemoglobin as a substrate was about 6.0 unit/mg. The molecular weight of the enzyme, as determined by gel exclusion chromatography was 33 000 and by polyacrylamide gel electrophoresis with SDS 31 600 (12.5% gel) and 27 000 (7.5% gel). The enzyme is an acidic glycoprotein (pI below 2.9) containing about 5% of carbohydrate. The pH optimum of the enzyme with haemoglobin was 6.0 at the optimal temperature of 40 degrees C in 15-min reaction. The enzyme showed the esterase activity (hydrolysis of BAEE) and was inactive with carbobenzoxy- and benzoyl-dipeptides with the following C-terminal amino acids: Phe, Tyr, Lys, Gly and Leu.
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PMID:Purification and characterization of a proteinase from Euphausia superba Dana (Antarctic krill). 353 51

A proteinase, which cleaves human third component of complement, was solubilized from erythrocyte membranes then purified by gel filtration chromatography, fluid phase electrophoresis, and hydroxylapatite chromatography. Labeling of the purified material by 125I or 3H-DFP and measurement of proteolytic activity subsequently isolated by SDS-polyacrylamide gel electrophoresis allowed to identify a 57 kDa single band, in non reducing conditions. Inhibition of this activity by PMSF supports covalent modification of an active serine residue. This membrane serine proteinase cleaved alpha and beta chains of human third component of complement, suggesting that p-57 is distinct from plasma serine proteinases.
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PMID:Identification of P-57, a serine proteinase, from human erythrocyte membranes, which cleaves both chains of human third component (C3) of complement. 353 96

A monoclonal antibody (V4G6) to rat tissue kallikrein (EC 3.4.21.35) has been developed and characterized. This clone showed no cross-reactivity with rat tonin, rat esterase A or human urinary kallikrein in either radioimmunoassay or enzyme-linked immunosorbent assay. The monoclonal antibody used in the direct radioimmunoassay detects purified rat urinary kallikrein in a range of 0.32 to 40 ng per tube. The displacement curves for rat submandibular gland, pancreatic and kidney extracts and urine were parallel with the standard curve of purified rat urinary kallikrein. Analysis of immunoprecipitates from [14C] DFP labeled submandibular gland extract with SDS-polyacrylamide gel electrophoresis, demonstrates that this antibody recognizes only one 38,000 dalton serine protease while polyclonal antiserum identifies multiple species. Using this specific monoclonal reagent, tissue kallikrein was localized immunohistochemically in the granular convoluted tubules and striated ducts of the rat submandibular gland and in the acinar cells of the rat pancreas. The results showed that the monoclonal antibody (V4G6) can specifically recognize a single kallikrein in the tissue extracts without cross-reacting with other kallikrein-related serine proteases. This monoclonal antibody can be used as a specific reagent for quantitation, identification and immunohistochemical studies of tissue kallikrein.
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PMID:A monoclonal antibody to rat tissue kallikrein: use in biochemical and immunohistochemical studies. 354 31

Larval acetylcholinesterase (acetylcholine acetylhydrolase) EC 3.1.3.7 of the trematode Schistosoma mansoni was characterized and purified by affinity chromatography. The enzyme was solubilized from sonicated cercarial tissue and showed a Km value of 1.83 mM and a Vmax value of 102 U/mg protein. It was characterized as a true AChE since it hydrolyses acetylthiocholine more than seven times faster than butyrylthiocholine, and since it was inhibited by high concentrations of substrate. The enzyme was purified by affinity chromatography on a Sepharose column of the inhibitor [N-(6-aminocaproyl-6-aminocaproyl)-m-aminophenyl] trimethyl ammonium. The purified enzyme eluted from the column by decamethonium bromide migrated as a single band of 500 kD on nondenaturing polyacrylamide gel electrophoresis (PAGE), whether stained for proteins or for enzymatic activity. Analysis by SDS-PAGE revealed two major polypeptide bands of 76 kD and 30 kD. By labeling the enzyme with 3H-DFP (di-isopropyl-fluorophosphate), the 30-kD polypeptide was shown to contain the active site of the enzyme, with an additional labeled band of 110 kD also being detected. On the basis of our data we suggest that the principal species of S. mansoni AChE is a tetramer of four subunit polypeptides each of MW ca. 110 kD which are not linked by disulfide bonds, and which are further cleaved into two fragments, one of MW 76,000 and one of MW 30,000, the latter bears the active site.
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PMID:Acetylcholinesterase of Schistosoma mansoni: purification and characterization. 372 10

A proteolytic activity associated with the microsomal fraction of L-5178Y/Esb tumor cells has been characterized. The enzyme has a molecular weight of 80-90 kD as determined by affinity-labelling with [3H]DFP and SDS-gel electrophoresis. It cleaves ester substrates at the carboxyl position of lysine and arginine and can activate the proenzyme plasminogen. The enzyme is found to be associated with the plasma membranes of high and low metastatic tumor cell lines and is shed in high-molecular-weight form mainly by the high metastatic variant. The pH optimum for esterase and protease activities was 7.5-8.5. Although similar to trypsin in substrate specificity, the enzyme was not inhibited by lima-bean trypsin inhibitor but was inhibited by DFP, PMSF, aprotinin and leupeptin. Partially purified preparations of the protease can alone degrade 125I-labelled endothelial cell extracellular matrix, pointing at the putative role of this enzyme in tumor invasion.
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PMID:Characterization of an extracellular matrix-degrading protease derived from a highly metastatic tumor cell line. 389 58


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