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)

Proteinase R and T purified from Tritirachiam album limber were characterized in comparison with proteinase K using circular dichroism (CD), enzyme activity, thermal melting, and sodium dodecylsulfate polyacrylamide gel electrophoresis (SDS-PAGE). CD analysis suggested that these three proteins possess some beta-sheet structure, with little alpha-helix except for proteinase R which showed about 14% alpha-helix. SDS-PAGE and gel filtration in 0.1% SDS indicated that proteinase T and K are resistant to SDS-induced unfolding similar to subtilisin. Thermal denaturation experiments showed the melting temperature for proteinase T to be 67 degrees and that for proteinase K to be 65 degrees in the absence of Ca2+, with higher melting temperatures in the presence of Ca2+. However, the enzyme activities of proteinase T and R were significantly lower than those of proteinase K.
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PMID:Comparative study on proteinase R, T, and K from Tritirachiam album limber. 207 93

Proteinase inhibitors have been shown to be capable of preventing various aspects of fertilization. Diisopropyl fluorophosphate (DFP) is an irreversible inhibitor of trypsin-like enzymes that is commercially available in a radiolabeled form. The experiments described herein were designed to determine if DFP would prevent sperm function in live, motile sperm and to identify the sperm proteins bound with DFP. DFP at 5 mM concentrations had no observable effect on sperm motility, but inhibited the penetration of zona-free hamster ova by human sperm (5.5%) compared to controls (33.5%). Acid extracts of motile sperm that had been incubated with radiolabeled DFP and collected by the swim-up procedure demonstrated the presence of radiolabeled DFP, and the autoradiography of the sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) gels of these extracts localized the uptake of radiolabeled DFP to proteins in the molecular weight region of the proacrosin-acrosin system. Acid-extracted proteinases from semen samples incubated with DFP demonstrated a concentration-dependent inhibition of both esterolytic hydrolysis of benzoyl-arginine ethyl ester on spectrophotometric analysis and proteolytic activity on gelatin SDS-PAGE zymography. DFP-labeled proteins were precipitated by highly specific antibodies to proacrosin. These results demonstrated that DFP is capable of inhibiting sperm function, and that it associates with the proacrosin-acrosin system in live motile sperm.
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PMID:Diisopropyl fluorophosphate labeling of sperm-associated proteinases. 211 Aug 39

In crude extracts of eggs of the soft tick Ornithodoros moubata, maximum degradation of vitellin is at pH 3-3.5, whereas no proteolysis is detected at neutral or weakly acidic pHs. Acidic proteolysis is maintained at high level throughout embryonic development, and rapidly decreases in the larva, during the high phase of yolk degradation. Proteinase, acid phosphatase, and N-acetylglucosaminidase are localized within the yolk spheres; these can be considered as lysosomal-like organelles containing both substrate (vitellin) and the degradative machinery. Proteolytic activity has been essentially attributed to a cathepsin L-like enzyme through substrate specificity and inhibitors. The molecular weight is 37,000 to 39,000 as shown using gelatin-containing SDS-PAGE activity gels. At neutral pH the enzyme binds to vitellin, as demonstrated by gel filtration and PAGE under nondenaturing conditions. Acid proteinase activity at pH 5-6 is undetectable both with proteins and synthetic substrates, but is strongly increased after preincubation at pH 3-4. Activation at low pH could be important in the regulation of yolk degradation.
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PMID:Yolk degradation in tick eggs: I. Occurrence of a cathepsin L-like acid proteinase in yolk spheres. 213 78

Chemical cleavage at cysteine residues with nitrothiocyanobenzoic acid shows that the last 98 amino acids of the 380-amino-acid sequence of chick muscle creatine kinase are sufficient for binding of the monoclonal antibody CK-ART. Removal of the last 30 amino acids by cleavage at methionine residues with CNBr results in loss of CK-ART binding. CK-ART binding is also lost when these C-terminal methionine residues are oxidized to sulphoxide, but binding is regained on reduction. Proteinase K 'nicks' native CK at a single site near the C-terminus and two fragments of 327 amino acides and 53 amino acids can be separated by subsequent SDS or urea treatment. CK-ART still binds normally to 'nicked' CK, which is enzymically inactive. After treatment with either urea (in a competition enzyme-linked immunosorbent assay) or SDS (on Western blots), however, CK-ART binds to neither of the two fragments, although these treatments do not affect binding to intact CK. This suggests that parts of both CK fragments contribute to the CK-ART epitope. CK-ART is both species- and isoenzyme-specific, binding only to chick M-CK. The only C-terminal regions containing chick-specific sequences are residues 300-312 and residues 368-371, the latter group being close to the essential methionine residues. We suggest that one, or possibly both, of these regions is involved in forming the conformational epitope on the surface of the CK molecule which CK-ART recognizes. Native CK is resistant to trypsin digestion. The C-terminal half of urea-treated and partly-refolded CK is also resistant to trypsin digestion, whereas the N-terminal half is readily digested. The results suggest a C-terminal region which can refold more rapidly than the rest of the CK molecule and provide evidence for an intermediate in CK refolding.
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PMID:Monoclonal antibody studies of creatine kinase. The ART epitope: evidence for an intermediate in protein folding. 246 57

Outer membranes were extracted from seven strains of Bacteroides bivius and six strains of B. disiens by the Sarkosyl method. Lipopolysaccharides (LPS) were extracted from the same strains by the Proteinase K method, and from three strains of each species by an aqueous phenol method. Analysis of the outer-membrane proteins by SDS-PAGE demonstrated that, within a species, very similar patterns with many shared or common bands were produced, but there were sufficient differences between species to allow separation. Immunoblotting with antisera raised against whole cells of each of the type strains showed that many antigens were shared between species. Smooth LPS was present in both species. By immunoblotting, the O-antigen of B. disiens was shown to be common to all six strains, and there was no cross-reaction between the B. disiens antiserum and B. bivius LPS. The O-antigen of B. bivius was not detected by immunoblotting with homologous antiserum, but antiserum to B. bivius reacted with a series of common low molecular mass antigens that were present in LPS preparations from strains of both species.
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PMID:Immunochemistry of the cell surfaces of Bacteroides bivius and Bacteroides disiens. 246 88

Human pancreatic kallikrein (H.Panc.K.) was purified from human pancreas by ion exchange chromatography on DEAE-cellulose, affinity chromatographies on p-aminobenzamidine Sepharose 6B and aprotinin aminocellulofine, followed by gel filtration on Sephacryl S-200. The final preparation had a specific activity of 9.2 AU/A280 (AU; amidase unit for H-Pro-Phe-Arg-MCA) and its N-terminal sequence coincided with the reported sequence for H.Panc.K.. In HPLC (gel filtration), one symmetrical peak corresponding to a molecular weight of 48,000 was obtained. In SDS-PAGE without 2-mercaptoethanol (2-ME), one band corresponding to a molecular weight of 52,000 was obtained, but with 2-ME, 2 bands, 52,000 and 30,000, were obtained. Km value for MCA was 4.9 x 10(-2) mM. Proteinase inhibitor specificities of H.Panc.K. were the same as those of human urinary kallikrein (HUK) and hog pancreatic kallikrein (hog Panc.K.), while anti-HUK antibody inhibited the activities of H.Panc.K. and HUK, but not that of hog Panc.K.. From the analysis of affinity for concanavalin A (Con A) and erythroagglutinating phytohemagglutinin (E-PHA), the carbohydrate parts of H.Panc.K. are relatively rich in biantennary complex type sugar chains with bisecting GlcNAc compared with those of human salivary kallikrein (H.Saliv.K.) and HUK.
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PMID:Characterization of human pancreatic kallikrein. 261 57

alpha-1-Proteinase inhibitor, formerly called alpha-1-antitrypsin, was detected in human corneal epithelium, stroma, Descemet's membrane and endothelium using an indirect immunolocalization technique. The average alpha-1-proteinase inhibitor levels detected by an immunodot blot assay in the epithelium, stroma and Descemet's membrane-endothelium extracts per total human cornea were 29.5 micrograms, 54.3 micrograms and 3.5 micrograms, respectively. Immunolocalization on Western blots of SDS polyacrylamide electrophoresis gels revealed that all three layers contained a molecule with a molecular weight equal to the native alpha-1-proteinase inhibitor. Additionally, in the epithelial and stromal extracts minor bands at 75 kD and 110 kD were noted which are possibly due to complexes with proteases. The 110 kD band alternatively may be a dimer of the inhibitor. The epithelial extract contained bands at 40 kd and less than 30 kD indicating the presence of proteolysis products. alpha-1-Proteinase inhibitor probably plays a major role in the protection of the cornea from proteases released by inflammatory cells.
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PMID:Localization and quantification of alpha-1-proteinase inhibitor in the human cornea. 278 99

The acrosomal matrix of hamster spermatozoa was enriched and characterized. Acrosomal matrices were released from spermatozoa with shaking in a pH 5.2 buffer containing Triton X-100 and protease inhibitors, and enriched on a glass-bead column. Phase-contrast microscopy indicated that 70-80% of the acrosomal matrices were released from the spermatozoa and only minor contamination from sperm heads was detected. Transmission electron microscopy confirmed the low level of contamination in the preparation and revealed a bilaminar structure similar but not identical to that of guinea-pig acrosomal matrix. One- and two-dimensional SDS-polyacrylamide gel electrophoresis (SDS-PAGE) showed the acrosomal matrix to be a complex structure enriched for several polypeptides. Proteinase activity was demonstrated by gelatin-SDS-PAGE. The major activity corresponded to bands of relative molecular masses (Mr) of 56,000, 51,000 and 48,000 with two minor bands of Mr 30,000 and 28,000. The lectin Pisum sativum agglutinin (PSA) bound to the anterior head of spermatozoa and isolated acrosomal matrix as judged by fluorescence microscopy using FITC-PSA. Western blots of spermatozoa and acrosomal matrices followed by overlay with biotinylated PSA indicated that there are at least two PSA-binding glycoproteins of Mr 60,000 and 72,000.
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PMID:Characterization of isolated acrosomal matrices from hamster spermatozoa. 329 98

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

An alkaline proteinase, previously identified in rat liver and heart, has been purified from the soluble fraction of human erythrocytes. The proteinase has an apparent molecular weight of 600 000 and is composed of eight subunits with molecular weights ranging from 32 000 to 21 000. The proteinase degrades both protein and synthetic peptide substrates with a broad pH optimum of 7.5-11.0. Among the synthetic peptides tested, tripeptides with arginine at the P1 position (e.g. Z-Val-Leu-Arg-4-methoxy-2-napthylamine and Boc-Leu-Gly-Arg-4-methylcoumarin-7-amide) are particularly good substrates. The proteinase appears to be sulfhydryl-dependent and is inhibited completely by mersalyl acid and by hemin; inhibitors of serine and metallo-type proteinases have no effect on proteinase activity. Interestingly, a variety of other proteinase inhibitors such as leupeptin, chymostatin and N-ethylmaleimide failed to completely inhibit protein-hydrolyzing activities of the enzyme. These results indicate that these activities may be accounted for by at least two different catalytic sites. Proteinase activity is stable in the presence of 1 M urea, 0.5% Triton X-100 or 0.03% SDS and is not affected by ATP. Based on the high molecular weight and sulfhydryl-dependence, we have named this proteinase macropain.
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PMID:Purification and characterization of a high molecular weight proteinase (macropain) from human erythrocytes. 353 Mar 30


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