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)

Myosin from rabbit stomach was highly purified by ammonium sulfate fractionation in the presence of ATP and MgCl2, ultracentrifugation and Sepharose 4B chromatography. The myosin composed of one heavy and two light chains as determined by SDS-gel electrophoresis. The molecular weights of the light chains were the same as those of gizzard myosin, about 20,000 and 17,000, respectively. The pH-activity curve and the KCl concentration dependency of Ca-ATPase of the stomach myosin were similar to those of other smooth muscle myosins. The stomach myosin was more resistant to pepsin digestion than skeletal myosin. Other proteolytic enzymes, trypsin, chymotrypsin, papain, and nagarse, digested the myosin in the same way as skeletal myosin.
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PMID:Purification and some properties of rabbit stomach myosin. 1 37

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.
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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.
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PMID:Purification and characterization of rat pepsinogens whose contents increase with developmental progress. 3 74

Human properdin (P) was found to be sensitive to the action of trypsin, chymotrypsin, pepsin, and Streptomycetes caesipitosus protease. Incubation of P with these enzymes resulted in loss of its functional activity and the production of antigenically deficient components compared to untreated P. Upon incubation with trypin, P was initially cleaved into a minor fragment and a major fragment. Further degradation ot the fragments occurred with prolongation of inculation time. The minor fragment was highly susceptible to further proteolysis compared to the major fragment which contained the carbohydrate moiety of the molecule. SDS-polyacrylamide gel electrophoretic analysis of trypsin-digested P suggested that the subunit polypeptide chains were initially cleaved at similar points to produce the major and minor fragments. The sedimentation velocity of the major fragment was higher than that of the intact molecule. The implications of these observations of the configuration of P are discussed.
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PMID:Effect of proteolytic digestion on the structure and function of human properdin. 5 3

Studies were performed to determine if cultured human endothelial cells synthesized basement membrane collagen. In culture, endothelial cells were attached to grossly visible membranous structures which on light microscopy were composed of ribbons of dense, amorphous material. On transmission electron microscopy, these membranous structures consisted of amorphous basement membrane, and material morphologically similar to microfibrils and elastic fibers. By immunofluorescence microscopy, these membranous structures stained brightly with antisera to human glomerular basement membrane. Cultured endothelial cells incorporated [3H]proline into protein; 18% of the incorporated [3H]proline was solubilized by purified collagenase. When endothelial cells were cultured with [14C]proline, 7.1% of the incorporated counts were present as [14C]hydroxyproline. Cultured endothelial cells were labeled with [3H]glycine and [3H]proline and digested with pepsin. The resulting fractions on analysis by SDS-polyacrylamide gel electrophoresis contained two radioactive protein peaks of mol wt 94,200 and 120,500. Both these peaks disappeared after digestion with purified collagenase. The peak of mol wt 120,500 corresponds to that of alpha1 (IV) collagen; the peak of the mol wt 94,200 probably corresponds to that of alpha1 (III) collagen. Thus, cultured human endothelial cells synthesize material which is morphologically and immunologically like amorphous basement membrane and biochemically like basement membrane collagen. Cultured endothelial cells probably also synthesize material which is morphologically similar to microfibrils and elastic fibers.
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PMID:Synthesis of basement membrane collagen by cultured human endothelial cells. 5 57

NeF was shown to be antigenically and structurally similar to IgG by the following experiments: (1) NeF activity in serum was absorbed by and, under acid conditions, could be eluted from (a) anti-myeloma IgG antibody coupled to Sepharose and (b) protein A-Sepharose. (2) Purified NeF could bind to anit-myeloma IgG-Sepharose and could be eluted with acid, and this binding was blocked by myeloma IgG. (3) An antibody to beta2, microglobulin, showing strong cross-reactivity with normal IgG, bound NeF activity before, but not after, absorption of the antiserum with IgG. (4) Sepharose-coupled antibodies to NeF could bind activity which was recovered in the acid eluate. This binding capacity was lost after absorption of the antibody with normal and myeloma IgG. (5) Structural similarity was demonstrated by pepsin and papain digestion, which resulted in NeF activity eluting with F(ab')2 and Fab fragments from protein A-Sepharose and Sephadex G-150. (6) Autoradiography of PAGE-SDS of 125I-labelled NeF eluted from EA43bBb cells showed that NeF had a larger H chain than normal IgG, suggesting that NeF might be an abnormal IgG molecule.
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PMID:The immunogloblin nature of nephritic factor (NeF). 9 36

The findings establish that type III collagen is a major constituent of grossly proliferated rheumatoid and normal synovium. Unlike the collagen of normal synovium most of that in rheumatoid tissue could be solubilised by pepsin at 4 degrees C. Moore than half the pepsin-solubilised collage was identified as type III, the remainder being type I, by CM-cellulose chromatography; SDS-polyacrylamide electrophoresis with and without reduction of disulphide bonds; and amino acid analysis. Moreover, at least half the total collagen in several samples of normal as well as rheumatoid tissue was clearly type III when cyanogen bromide-derived peptides were run on SDS-polyacrylamide electrophoresis and compared with peptides prepared from purified types I and III collagens. This conclusion was supported by the isolation on phosphocellulose and quantitation by amino acid analysis of the collagen peptides alpha(1)CB2 and alpha(III)CB2 from a cyanogen bromide digest of rheumatoid synovium.
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PMID:Type III collagen: A major constituent of rheumatoid and normal human synovial membrane. 13 Feb 25

The cyanogen bromide peptides from insoluble and pepsin solubilised type I collagen of bovine bone, dentine, meniscus, tendon, skin and cornea were compared by SDS-polyacrylamide gel electrophoresis. In each case alpha 1CB6 was shown to be the only peptide of molecular weight greater than 10 000 involved in cross-linking. The major helical peptides alpha 1CB3, alpha 1CB8, alpha 1CB7 and alpha 2CB4 were not implicated in cross-linking in any tissue either by end overlap or helix-helix interaction. The C-terminal alpha 2 chain peptide alpha 2CB3,5, which contains a large helical region, was not involved in cross-linking to any large peptides, although a slight increase in molecular weight in all tissues examined did suggest a possible interaction(s) with a very small peptide of molecular weight 4--5000.
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PMID:Bovine type I collagen: A study of cross-linking in various mature tissues. 50 99

An acid protease from Monascus kaoliang was purified by consecutive applications of fractional acetone precipitation, batchwise CM-cellulose method and DEAE-cellulose column chromatography. The preparation was homogeneous on disc polyacrylamide gel electrophoresis at pH 4.5 and 7.5. The yield was about 30% with overall increase in specific activity of about 6-fold. The molecular weight as determined by SDS gel electrophoresis was about 34,000. The enzyme was a glycoprotease as indicated by specific carbohydrate staining on gels. It possessed the nature of an acid protease with a pH optimum at 3.0 toward heat-denatured casein and was stable over the range of pH 3.0 to 6.0. Reducing agents and thiol poisons had no effect on this enzyme, suggesting that free sulfhydryl groups were not required for enzyme activity. Diisopropyl fluorophosphate did not inactivate this protease, indicating the probable absence of serine residue in the active site. The enzyme was inactivated by reaction with the carboxy-group specific reagent, 1,2-epoxy-3-(p-nitrophenoxy) propane (EPNP). Pepstatin, a specific inhibitor for pepsin, was shown to inhibit this enzyme strongly. However, biacetyl (2,3-butadione) had little effect on this protease, although it inactivated pepsin to an 85% activity loss. Also, p-bromophenacyl bromide, another specific inhibitor of pepsin, failed to inactivate this acid protease.
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PMID:Purification and characterization of an acid protease from Monascus kaoliang. 74 88

For the first time, it has been possible to solubilize a significant amount of heart valve collagen from 6 month old pigs by pepsin treatment. Chromatographic and electrophoretic analysis of this pepsin-soluble collagen gives evidence for the presence of two types of collagen molecules: type I collagen and another type which has properties similar to those of type III collagen. For example, this collagen, present as a gamma component, gives rise, when reduced by dithiothreitol, to two bands by SDS-acrylamide gel electrophoresis: a beta band and an alpha band. Furthermore, the collagenic web of this tissue is highly polymerized, which explains the inability to solubilize all of the collagen molecules and the presence of high-molecular-weight molecules in the pepsin-soluble fractions.
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PMID:Collagen heterogeneity in pig heart valves. 77 39


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