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)

An esterase which hydrolyses the cephalosporin antibiotic, cefuroxime axetil has been isolated from rat intestinal washings and purified. Closely related cefuroxime esters were extremely poor substrates, but p-nitrophenyl acetate and alpha-naphthyl acetate were slowly hydrolysed by the purified enzyme. Analysis by gel filtration gave an Mr = 51,000 and on SDS-polyacrylamide gel electrophoresis the esterase resolved into two main bands of Mr = 31,500 and 26,800. Analytical isoelectric focusing resolved purified esterase into multiple forms active toward alpha-naphthyl acetate, the isoelectric points of which ranged from pH 4.5 to 6.3. The esterase bound specifically to Con A-Sepharose suggesting it could be a glycoprotein. Esterase activity was unaffected by the presence of dihydroxy bile salts (1-8 mM) and inhibition studies using organophosphates and eserine salicylate have classified the enzyme as a carboxylesterase.
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PMID:Purification and partial characterization of rat intestinal cefuroxime axetil esterase. 360 43

Two arginine ester hydrolases, designated EI and EII, consist of multiple molecular forms with pI values in the range 4.0-4.6 for EI and 3.3-3.9 for EII. Isoforms had identical molecular weights: 38,500 for EI and 41,000 for EII (SDS electrophoresis). The N-terminal amino acid for both enzymes was valine and their amino acid contents were very similar, with both containing carbohydrate. After treatment of EI and EII with neuraminidase both enzymes migrated identically in the electrofocusing system. Neither esterase hydrolyzed casein, alpha-N-benzoyl-DL-arginine-p-nitroanilide (BAPNA), yet both hydrolyzed alpha-N-benzoyl-L-arginine methylester (BAEE), p-tosyl-L-arginine methylester (TAME) and Pro-Phe-Arg-MCA. The esterase activities of the two enzymes were inhibited by organophosphorus inhibitors and benzamidine. The Km value for EI with BAEE was 3.3 X 10(-5) M, with TAME 3.0 X 10(-5) M, and for EII 2.7 X 10(-5) M (BAEE) and 5.9 X 10(-5) M (TAME). EII possessed kinin-releasing activity, as shown by the twitch response of an isolated rat uterus. The physiological role of EI is unknown. Neither esterase has thrombin-like or fibrionlytic activities.
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PMID:Purification and characterization of two arginine ester hydrolases from Vipera berus berus (common viper) venom. 361 75

A relatively simple procedure for isolation and purification of human blood plasma kallikrein (HPK) by QAE-Sephadex A-50 SP-Sephadex C-50 and affinity chromatography on Sepharose 4B with immobilized soybean trypsin inhibitor with the activity yield of about 40% has been developed. The method allows for simultaneous isolation of low (LMW) and high molecular weight (HMW) kininogens from the same HPK sample. HPK preparations are homogeneous upon 7.5% polyacrylamide gel electrophoresis in the presence of 0.1% SDS; its Mr is 90,000. After treatment with beta-mercaptoethanol, HPK dissociates into two fragments with Mr of 43,000 and 37,000. HPK preparations have high specific activities of esterase (31 microM/min), amidase (78 microM/min), and kininogenase (420 micrograms equiv. bradikinin/min). The high degree of protein purification was demonstrated by titration of active centers with 4-methylumbelliferylguanidine benzoate. The values of equilibrium dissociation constants for the HPK complex with aprotinin (Ki) equal to 1 X 10(-8) M (ethyl ester of N-alpha-benzoyl-L-arginine) and 1,5 X 10(-9) M (HMW) were determined. The kinetics of HPK-induced liberation of bradikinin from purified preparations of HMW and LMW was studied. The kinetic parameters (Km, kcat and kcat/Km) of this reaction suggest a high affinity of HPK for HMW, but not for LMW. LMW does not compete with HMW for the enzyme active center. It is assumed that LMW is not a physiological substrate for HPK.
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PMID:[Various properties and kinetics of interaction of high and low molecular weight human kininogens with human plasma kallikrein]. 363 30

Acetyl esterase (acetic-ester acetylhydrolase, EC 3.1.1.6) from bull testes was purified 325-fold by ammonium sulphate precipitation, chromatography on DEAE-cellulose, hydroxyapatite and finally, gel filtration on a Sephadex G-200 column. The purified enzyme appeared as a single protein band on native polyacrylamide gel electrophoresis and in isoelectric focusing (pI 5.25). In both methods, the activity coincided with the protein band. A single protein band corresponding to Mr 70,000 was obtained by SDS-polyacrylamide gel electrophoresis. The reported amino-acid composition indicates that the enzyme contains three half-cystine residues, of which only one could be detected, by titration, as a free -SH group. No free amino terminal was detected by dansylation.
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PMID:Purification and characterization of acetyl esterase from bull testes. 368 93

The tissular origin of alkaline phosphatase was evaluated in canine seminal plasma. Alkaline phosphatase activity was most concentrated in the first fraction of the split ejaculate and was virtually undetectable in the third and fourth fractions. By contrast, arginine esterase, a known marker of dog prostatic secretion, was present in similar concentrations in all fractions of the split ejaculates analyzed by SDS gel electrophoresis. Similarly, arginine esterase was very abundant in secretory granules prepared from dog prostate homogenates, whereas these granules contained virtually no alkaline phosphatase. Among male sex accessory organs, alkaline phosphatase activity was very high in the epididymis and much lower in the testis and prostate. Furthermore, the specific activity in epididymal fluid collected from the cauda epididymis was about 10 times higher than in the corresponding epididymal homogenates. These results show that the major portion of alkaline phosphatase in dog seminal plasma does not come from the prostate but from the epididymis.
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PMID:Origin of alkaline phosphatase of canine seminal plasma. 377 20

Antibodies raised against esterase-4 and esterase-5 from Drosophila mojavensis were coupled to Protein A-Sepharose CL-4B to prepare high-efficiency immunomatrices used for their purification. Final purification was achieved by anion-exchange h.p.l.c., in the case of esterase-5 followed by gel-filtration h.p.l.c. The resultant esterase preparations were homogeneous, as judged by gel-filtration h.p.l.c., SDS/polyacrylamide-gel electrophoresis and non-denaturing gel electrophoresis. Esterase-4 and esterase-5 are the products of a duplicated gene. They are differently localized in the insect's body and expressed in different periods during development. Although both enzymes exhibit little immunological cross-reactivity, their amino acid compositions show few significant differences and their N-terminal sequences are largely identical, which clearly show their common origin.
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PMID:Structural comparison of two esterases from Drosophila mojavensis isolated by immunoaffinity chromatography. 380 Sep 57

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

We have cloned and determined the nucleotide sequence of the gene ereA of plasmid pIP1100 which confers high-level resistance to erythromycin (Em) in Escherichia coli. The gene was defined by initiation and termination codons and by in vitro insertion-inactivation into an open reading frame (ORF) of 1032 bp corresponding to a product with an Mr of 37 765. However, the enzyme, an Em esterase, displayed an apparent Mr of 43 000 upon electrophoresis of a minicell extract on the SDS-polyacrylamide gels. The G + C content (50.5%) of the gene ereA and the preferential codon usage in its ORF suggest that this resistance determinant should be indigenous to E. coli.
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PMID:Nucleotide sequence of the gene ereA encoding the erythromycin esterase in Escherichia coli. 389 61

Proteolytic enzymes in extracts of human sperm have been identified and partially characterized using a technique which incorporates gelatin into a sodium dodecyl sulfate-polyacrylamide gel electrophoresis (gelatin-SDS-PAGE) system. Initially, semen characteristics from four donors were evaluated. Following this, washed sperm were acid extracted and proacrosin and acrosin activities determined spectrophotometrically. Proteinase activity in unactivated sperm extracts was then extracts was then demonstrated using the gelatin-SDS-PAGE system. Three major (Mr approximately equal to 47,000-54,000) and four faint (Mr approximately equal to 34,000-38,000) bands of digestion were observed. Upon activation of sperm extracts it was observed that maximum esterase activity occurred within 7 min of activation while maximum proteinase activity required approximately 15 min. When gels were washed and incubated in the presence of 50 mM benzamidine, no digestion bands were observed. This indicates that all of the digestion bands were due to trypsin-like proteinases. Finally, upon serial dilution of sperm extracts it was found that this SDS-PAGE system is sensitive enough to detect proteinase activity from as few as 30,000 sperm.
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PMID:Evaluation of the human sperm proacrosin-acrosin system using gelatin-sodium dodecyl sulfate-polyacrylamide gel electrophesis. 392 46

Four active forms of chymotrypsin C (C1, C2A, C2B, and C3) were isolated from the autolyzed porcine pancreas glands. Their molecular weights were estimated by SDS-polyacrylamide gel electrophoresis to be 29 100 for C1, 26 300 for C2A and C3, and 25 500 for C2B. The kinetic analyses of esterase activity of the enzymes toward Ac-LLeu-OEt and Ac-LPhe-OEt showed that chymotrypsin C1 hydrolyzed the two substrates more efficiently than did chymotrypsin C3. Chymotrypsin C1 consisted of chain A (H-Cys-...-Asn-OH, Mr 886) and chain BC (H-Val-...-Lys-OH, Mr 28 200). Chymotrypsin C3 consisted of the two components of C3L and C3S that could be dissociated in the presence of 2.3% SDS. C3L consisted of the chain A and the chain C (H-Ser-...-Lys-OH, Mr 13 600). C3S was the chain B (H-Val-...-Lys-OH, Mr 11 800). These kinetic and chemical analyses show that chymotrypsins C1 and C3 correspond to chymotrypsin A delta and A alpha, respectively.
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PMID:Active forms of chymotrypsin C isolated from autolyzed porcine pancreas glands. 404 69


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