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

Two kinds of cathepsin D were found in Japanese monkey lung and were named cathepsins D-I and D-II. Cathepsin D-I was partially purified by ammonium sulfate fractionation and DEAE-cellulose column chromatography. It had properties common to other ordinary cathepsins D in terms of the elution position from a DEAE-cellulose column at pH 8.0, the pH-dependence of activity toward acid-denatured hemoglobin, and the molecular weight of 35,000 as determined by Sephadex G-100 gel filtration. On the other hand, cathepsin D-II was purified about 1,000-fold by a combination of ammonium sulfate fractionation and column chromatographies on DEAE-cellulose and Sephadex G-100. It was a very acidic protein as judged from its elution position from a DEAE-cellulose column at pH 8.0, and the high mobility toward the anode on disc gel electrophoresis at pH 8.6. Its molecular weight was determined to be 35,000 by Sephadex G-100 gel filtration and 39,000 by SDS-polyacrylamide gel electrophoresis. It was optimally active at pH 2.8 against acid-denatured hemoglobin as a substrate, showing 80% of the optimal activity at pH 1.0, and almost no activity above pH 4.0. This pH-profile of activity was similar to that of monkey pepsin C (gastricsin). It did not hydrolyze N-acetyl-L-phenylalanyl-3,5-diiodo-L-tyrosine, a synthetic substrate for pepsin, but was inhibited by a series of pepsin inhibitors such as pepstatin, 1,2-epoxy-3-(p-nitrophenoxy)propane, p-bromophenacyl bromide, and diazoacetyl-DL-norleucine methyl ester, although the diazo reagent was a rather weak inhibitor of the enzyme. The amino acid composition of cathepsin D-II was found to be fairly different from those of other cathepsins D. However, it showed a striking resemblance to that of Japanese monkey pepsinogen C, suggesting some evolutionary relationship between them.
 ...
PMID:The structure and function of acid proteases. VIII. Purification and characterization of cathepsins D from Japanese monkey lung. 2 23

Two pepsinogens, the contents of which increase with developmental progress, were purified from the gastric mucosa of the adult rat by ammonium sulfate fractionation and chromatography on DEAE-cellulose and DEAE-Sepharose CL-6B columns. The purified zymogens, designated as pepsinogens I and II, were each shown to be homogeneous by polyacrylamide gel disc electrophoresis. Pepsinogen II had a greater electrophoretic mobility toward the anode at pH 8.0 than pepsinogen I. The molecular weights of both zymogens were estimated to be 38,000 by SDS-polyacrylamide gel electrophoresis. The activated enzymes, pepsins I and II, each had the same molecular weight of 32,000. The pH optima for both enzymes were found to be 2.0. The enzymes showed high stabilities at pH 8.0, while they lost their activities within 60 min at pH 10.0. The enzymes were inhibited by pepstatin and diazoacetyl-DL-norleucine methyl ester (DAN). The activities of the enzymes in hydrolyzing N-acetyl-L-phenylalanyl-3,5-diiodo-L-tyrosine (APDT) were about 1/8 of that of porcine pepsin. These results suggest that pepsins I and II are very similar.
 ...
PMID:Purification and characterization of rat pepsinogens whose contents increase with developmental progress. 3 74

C1 inactivator (C1 INA) was highly purified from rabbit serum. C1 INA thus purified was a single polypeptide chain with a molecular weight of 105,000 or 140,000, as estimated by SDS-polyacrylamide gel electrophoresis or gel filtration on Sephadex G-200, respectively. It inhibited rabbit and also human C1, when the C1 activities were measured in terms of hydrolyses of acetylglycyl-L-lysine methylester, N-alpha-acetyl-L-arginine methylester and N-alpha-acetyl-L-tyrosine ethylester. These properties showed that rabbit C1 INA bears a marked structural similarity to human C1 INA. Furthermore, rabbit C1 INA was capable of inhibiting similarly both rabbit C1s and its active fragment lacking a half of the H chain of C1s, indicating that deletion of a half of the H chain did not affect the susceptibility of C1s to the inhibitory activity of C1 INA.
 ...
PMID:Purification and some properties of rabbit C1 inactivator. 92 87

A high affinity cyclic nucleotide binding phosphatase was purified to homogeneity from potato tubers by a rapid procedure involving batchwise elution from carboxymethylcellulose and gel filtration. The phosphatase has a molecular weight of 28,000 as estimated from both SDS-PAGE and gel filtration. The phosphatase binds to Con A-agarose and is eluted by 0.5 M alpha-methylglucoside. The phosphatase catalyses the hydrolysis of nucleoside monophosphates, p-nitrophenylphosphate and O-phospho-L-tyrosine, but not of O-phospho-L-serine or O-phospho-L-threonine. N-terminal sequencing of the phosphatase has revealed significant homology with two similar-size soybean leaf and stem storage glycoproteins.
 ...
PMID:Rapid purification and N-terminal sequencing of a potato tuber cyclic nucleotide binding phosphatase. 138 14

1. The L-amino acid oxidase of the monocellate cobra (Naja naja kaouthia) venom was purified to electrophoretic homogeneity. The molecular weight of the enzyme was 112,200 as determined by Sephadex G-200 gel filtration chromatography, and 57,400 as determined by SDS-polyacrylamide gel electrophoresis. 2. The enzyme had an isoelectric point of 8.12 and a pH optimum of 8.5. It showed remarkable thermal stability, and, unlike many venom L-amino acid oxidase, was also stable in alkaline medium. The enzyme was partially inactivated by freezing. 3. The enzyme was very active against L-phenylalanine and L-tyrosine, moderately active against L-tryptophan, L-methionine, L-leucine, L-norleucine, L-arginine and L-norvaline. Other L-amino acids were oxidized slowly or not oxidized. 4. Kinetic studies suggest the presence of a side-chain binding site in the enzyme, and that the binding site comprises of at least four hydrophobic subsites.
 ...
PMID:Purification and properties of the L-amino acid oxidase from monocellate cobra (Naja naja kaouthia) venom. 161 86

Marthasterias glacialis sperm cells were treated with ionophore A23187, centrifuged, and the supernatants were assayed for esterase activity. With N-benzoyl-L-arginine ethyl ester-HCl (BAEE) as substrate, a net activity was determined which was not detectable when N-acetyl-L-tyrosine ethyl ester (ATEE) was used. The BAEE trypsin-like activity was inhibited by soybean trypsin inhibitor (SBTI), N-alpha-p-tosyl-L-lysine chloromethyl ketone-HCl (TLCK), and phenyl methyl sulfonyl fluoride (PMSF), but not by L-1-tosylamido-2-phenylethyl chloromethyl ketone (TPCK). The presence of proteolytic activity in acrosomal exudates was further demonstrated by gelatin-sodium dodecyl sulfate-polyacrylamide gel electrophoretic zymography (gelatin-SDS-PAGE). The presence of several bands of low proteolytic activity and of one band of high proteolytic activity, which also has the lower molecular weight, together with the fact that all are inhibited by benzamidine, suggests the existence of a trypsin-like proteinase system. The effect of the acrosomal exudate on the oocyte jelly coat was investigated by SDS-PAGE analysis. All jelly proteins appeared to be digested by the acrosomal enzymes. Furthermore, if SBTI is added shortly after insemination, the sperm fail to fertilize the oocytes. These results indicate that the starfish sperm acrosomal vesicle contains a trypsin-like protease which may be involved in sperm penetration through the oocyte jelly coat.
 ...
PMID:Presence of a trypsin-like protease in starfish sperm acrosome. 162 66

A protein that catalyzes the decoloration of dopachrome has been partially purified from B16 mouse melanoma tumors. The enzyme is preferentially associated to the melanosomes, but it is also found in the microsomal and cytosolic fractions of cellular homogenates. The protein is clearly different from tyrosinase, and should be related to the dopachrome oxidoreductase (Barber et al. (1984) J. Invest. Dermatol. 83, 145-149) and the dopachrome conversion factor (Korner and Pawelek (1980) J. Invest. Dermatol. 75, 192-195) since the reaction product of dopachrome conversion is 5,6-dihydroxyindole-2-carboxylic acid. The protein appears to have an oligomeric structure, with a molecular mass slightly higher than 300 kDa estimated by gel filtration, whereas the molecular mass of the monomer might be approx. 46 kDa estimated by SDS-PAGE electrophoresis. Its Km for dopachrome is around 100 microM. The enzyme is competitively inhibited by indoles and is unaffected by metal chelators. It also has the ability to increase the amount of melanin formed from L-tyrosine by melanoma tyrosinase, and therefore, cannot be considered an 'indole blocking factor' as was suggested for the related dopachrome oxidoreductase. Since the reaction catalyzed by the enzyme is a tautomeric shift on dopachrome, we would propose dopachrome tautomerase (EC 5.3.2.3) as the most precise and informative name.
 ...
PMID:Regulation of mammalian melanogenesis. I: Partial purification and characterization of a dopachrome converting factor: dopachrome tautomerase. 216 85

An enzyme which catalyzes the transamination of L-aspartate with 2-oxoglutarate has been purified 400-fold to electrophoretic homogeneity from the unicellular green alga Chlamydomonas reinhardtii 6145c. An apparent relative molecular mass of 138,000 was estimated by gel filtration. The enzyme is a dimer consisting of two identical subunits of Mr 65,000 each as deduced from PAGE/SDS studies. A stoichiometry of two molecules pyridoxal 5-phosphate/enzyme molecule was calculated. The enzyme has an isoelectric point of 8.48 and its absorption spectrum exhibits a maximum at 412 nm which is shifted to 330 nm upon addition of L-aspartate. L-Aspartate or pyridoxal 5-phosphate, but not 2-oxoglutarate, protected the enzyme from heat inactivation. The purified enzyme was able to transaminate, although to a low extent, L-phenylalanine and L-tyrosine with 2-oxoglutarate, and L-serine, L-alanine and L-glutamine with oxaloacetate. L-Aspartate aminotransferase exhibited hyperbolic kinetics for 2-oxoglutarate and oxaloacetate, and nonhyperbolic behaviour for L-aspartate and L-glutamate. Apparent Km values were 0.55 mM for 2-oxoglutarate, 0.044 mM for oxaloacetate, 2.53 mM for L-aspartate and 3.88 mM for L-glutamate. Transamination of L-aspartate in C. reinhardtii is a bisubstrate reaction with a bi-bi ping-pong mechanism, and is not inhibited by substrates.
 ...
PMID:Purification and properties of L-aspartate aminotransferase of Chlamydomonas reinhardtii. 233 83

The synthetic monovalent antigen L-tyrosine-p-azophenyltri-methylammonium (tyr (TMA)) induces in A/J mice, a cascade of regulatory T cells in the absence of any detectable effector function (e.g., CTL, delayed-type hypersensitivity, etc.). An important component of the activated T cells is a first order suppressor T cell or Ts1 that is Ly-1+2-, functions only at the afferent limb of the anti-TMA response, binds the TMA ligand and bears cross-reactive idiotypes associated with anti-TMA antibodies. This Ts1 produces a suppressor factor (TsF1) that binds the TMA ligand, bears the cross-reactive idiotypes and I-J determinants and functions to induce an idiotype-specific Ts2 population. To study the biochemistry of this TsF, use was made of T cell hybridomas that constitutively produce TMA-TsF1 (8A.1 and 8A.3). The TsF1 was purified from culture supernatant or cell extracts by (NH4)2SO4 precipitation, reverse phase HPLC and either affinity chromatography or by preparative IEF. The TsF1 has an isoelectric point of 6.5 and a m.w. of 26,000 or 62,000 as analyzed by SDS-PAGE or high performance molecular sieve chromatography. Its precipitation in 30 to 40% (NH4)2SO4; elution pattern from reverse phase high performance columns; its capacity to bind to a mAb specific for L-glutamic acid 60L-alanine30-L-tyrosine10 (GAT)-TsF1 strongly suggest that this protein belongs to the same family of proteins as do the GAT-TsF1 described previously. Most noteworthy is that although these TsF1 proteins show remarkable similarities, they are absolutely specific in their biologic activity; TMA-TsF1 will not suppress the response to GAT-BA-TNP and GAT-TsF1 will not suppress the response to TMA-BA-TNP. Thus the TMA-TsF1 represents a second example of a unique group of Ag-specific proteins whose function is to induce or activate other suppressor T cells in the primary immune response to Ag.
 ...
PMID:Purification and analysis of an antigen-specific suppressor factor from a T cell hybridoma specific for phenyltrimethylamino hapten. 246 88

Microbial tyrosine decarboxylase (EC 4.1.1.25) and mammalian aromatic-L-amino-acid decarboxylase (EC 4.1.1.28) catalyse the formation of tyramine from L-tyrosine. These enzymes were characterised after isolation to purity by methods including fast polymer liquid chromatography (FPLC). Tyrosine decarboxylase was isolated from Streptococcus faecalis by FPLC anion exchange chromatography (11-times purification; 72% recovery; 23.2 U/mg protein). FPLC on Phenyl-Superose resulted in purification to 115 U/mg protein. Aromatic-L-amino-acid decarboxylase was isolated from pig kidney by ammonium sulfate fractionation, DEAE chromatography, and FPLC anion exchange chromatography (21-times purification; 22% recovery; 0.71 U/mg protein). By FPLC chromatofocusing, tyrosine decarboxylase eluted at pH 4.3 and aromatic-L-amino-acid decarboxylase at pH 5.0. Isoelectric focusing of tyrosine decarboxylase gave two bands (pI 4.4 and 4.5). With pyridoxal 5'-phosphate removed by ultrafiltration, only one band (pI 4.4) appeared, and SDS polyacrylamide electrophoresis confirmed the purity. FPLC gel filtration resulted in molecular weights 143,000 and 86,000, respectively, for tyrosine decarboxylase and aromatic-L-amino-acid decarboxylase. In SDS electrophoresis, tyrosine decarboxylase had the monomer molecular weight 75,000, showing a dimer structure for the enzyme.
 ...
PMID:Purification and characterisation of tyrosine decarboxylase and aromatic-L-amino-acid decarboxylase. 250 58


1 2 3 4 5 Next >>