Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.1.27.4 (ribonuclease)
 6,621 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Purpura was grossly observable in albino mice 6 to 8 h after the intraperitoneal injection of sterile, deoxyribonuclease-treated, cell-free extracts prepared by sodium deoxycholate-induced lysis, sonic disruption, Parr bomb treatment, autolysis without sodium deoxycholate, or alternate freezing and thawing of washed suspensions of Streptococcus pneumoniae type I. Cell-free extracts obtained from sonically disrupted, heat-killed cells (100 degrees C for 20 min) did not contain purpurogenic activity. The reaction was maximal at approximately 24 h postinjection, started to fade slowly after 24 to 48 h, and usually was not grossly observable by 4 to 6 days postinjection. The purpura-producing principle (PPP) in the cell-free extract was purified by sequential ammonium sulfate precipitation, protamine sulfate precipitation, Sepharose 6B gel filtration, wheat germ lectin-Sepharose 6MB affinity chromatography, ribonuclease and trypsin treatment, and a second Sepharose 6B gel filtration step. The final preparation (i) contained glucosamine (5.6%), muramic acid (8.0%), neutral carbohydrate (12.8%), phosphate (8.0%), orcinol-reactive material (6.0%), and Lowry-reactive material (1.6%), and (ii) was free of detectable amounts of deoxyribonucleic acid, capsular polysaccharide, neuraminidase, cytolysin, and hyaluronidase. The isoelectric point and molecular size of the PPP were approximately pI 3.0 and several million daltons, respectively, and the activity remained in the supernatant fluid after centrifugation for 1 day at 105,000 x g. PPP activity was destroyed by incubation with egg white lysozyme and sodium metaperiodate but was resistant to trypsin, pronase, alpha-amylase, deoxyribonuclease, ribonuclease, alkaline phosphatase, pancreatic lipase, 7% trichloroacetic acid, 6 M urea, autoclaving (121 degrees C) for 30 min, and mild acid and alkali exposure. Our observations indicate that the PPP requires intact beta-1,4-glucosidic linkages for activity and support the working hypothesis that activity is associated with pneumococcal peptidoglycan solubilized by the bacterium's autolysin.
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PMID:Characterization of pneumococcal purpura-producing principle. 624 53

All strains of Legionella pneumophila tested produced detectable levels of extracellular protease, phosphatase, lipase, deoxyribonuclease, ribonuclease, and beta-lactamase activity. Weak starch hydrolysis was also demonstrated for all strains. Elastase, collagenase, phospholipase C, hyaluronidase, chondroitinase, neuraminidase, or coagulase were not detected in any of these laboratory-maintained strains.
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PMID:Extracellular enzymes of Legionella pneumophila. 626 49

The effect of various treatments on the activity of anti-treponemal lymphotoxin (ATL) produced by lymphocytes of syphilitic rabbits was studied. Treponema pallidum-killing activity of ATL was slightly reduced after heating at 56 degrees C and completely abolished at 100 degrees C. The significant reduction of the activity was also obtained after exposure of ATL to acidic conditions (pH 1-5) at room temperature, or by treatment with papain and neuraminidase. Activity of ATL was completely resistant to deoxyribonuclease, ribonuclease and trypsin treatment. ATL was eluted from the Sephadex G-100 column together with hemoglobin, that suggested the apparent molecular weight of ATL of about 65,000. The active fraction from the Sephadex G-100 column was further fractionated on DEAE-Sephadex A-50. The activity of ATL was widely spread in the column eluate, indicating the charge heterogeneity. All these data indicate that ATL is a relatively low molecular weight protein. The sensitivity to neuraminidase and heterogeneity of charge suggest that it is a glycosylated protein.
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PMID:Characterization of anti-treponemal lymphotoxin from lymphocytes of syphilitic rabbits. 638 57

The binding of human 125I-labeled lactoferrin (LF) to a population of adherent mononuclear cells (ADMC) and nonrosetting lymphocytes (E-) was abolished by prior treatment of the cells with deoxyribonuclease (DNase), but not ribonuclease (RNase). When DNase-treated ADMC were incubated with exogenous DNA, the binding of 125I-LF was restored. Enzymatic digestion with other enzymes, trypsin, phospholipase D, and neuraminidase, did not significantly influence 125I-LF binding. Saturable binding of LF at 0 degrees C was demonstrated for both E- and ADMC, with equilibrium dissociated constants of 0.76 x 10(-6) M and 1.8 x 10(-6) M, respectively. E- cells bound 2.5 x 10(7) and ADMC bound 3.3 x 10(7) molecules of Lf at saturation. Cell membranes were isolated from ADMC, E- and E+ and reacted with 125I-labeled LF; significant binding was only seen with ADMC and E-. Prior treatment of the membranes with DNase abolished the binding. Immunofluorescence studies indicated that a population of ADMC and E-, but not E+, exhibited a peripheral staining pattern for LF. Prior treatment of ADMC and E- with DNase abolished the surface immunofluorescence. This study provides evidence that cell membrane DNA acts as a binding site for exogenous LF. This is a novel role for DNA that has not been previously reported. Furthermore, it points to a basic difference between E+ cells vs. ADMC and E- cells in respect to their possession of cell surface DNA.
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PMID:Lactoferrin binds to cell membrane DNA. Association of surface DNA with an enriched population of B cells and monocytes. 660 Jul 47

The presence of glycosaminoglycans (GAG) has been histochemically demonstrated in the CNS of various mammalian species. They have been related with some nerve functions as neurotransmitters storage and synaptic transmission. In the present paper, the histochemical properties of nerve cell cytoplasmic GAG were studied in several regions of adult human CNS. Samples of brain cortex, pons, upper medulla, and cerebellar cortex obtained by autopsy from subjects not dying after neurological diseases were fixed by immersion in glutaraldehyde, dehydrated with ethanol, and embedded in paraffin. The sections were stained with Alcian blue solutions adjusted to pH 2.5, 4.0, and 5.7. To the latter solution MgCl2 was added in increasing concentration from 0.05 to 1.2 M. Testicular hyaluronidase, neuraminidase, and ribonuclease were applied on simultaneous sections with their respective controls. The sequence of these reactions allowed us to demonstrate the presence of hyaluronic acid along chondroitin-4- and/or 6-sulphate in the cytoplasm of most nerve cells. The sulphated GAG showed certain variability in the various regions studied related specially with their grade of sulphation.
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PMID:Histochemical demonstration of cytoplasmic glycosaminoglycans in the macroneurons of the human central nervous system. 670 30

Oral cholera vaccine contains 45% of O-antigen (serovars Ogawa and Inaba in equal parts) and at least 9 serologically active proteins; of these, toxoid (about 60% of the total amount of protein) and 5 enzymes have been identified: neuraminidase, proteinase, ribonuclease, phospholipase and ATPase. The safety, absence of reactogenicity and definite immunological effectiveness of the preparation in the primary immunization of volunteers have been shown.
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PMID:[Biochemical and immunochemical characteristics of a new oral, chemical cholera bivalent vaccine and results of a trial of the preparation on volunteers]. 676 Jun 28

A pancreas-specific antigen was identified by immunologic techniques and purified from saline extract of human pancreas. The purified pancreas-specific antigen was shown to be homogeneous by polyacrylamide gel electrophoresis under both denaturing and non-denaturing conditions. It had a molecular weight of 44000 as estimated by gel filtration or sodium dodecyl sulfate-gel electrophoresis, and a sedimentation coefficient of 3.4 S as analyzed by sucrose gradient centrifugation. Pancreas-specific antigen possessed an isoelectric point of 4.9 and migrated to alpha-beta region upon immunoelectrophoresis. By colorimetric assay procedures, pancreas-specific antigen exhibited no enzyme activity, such as amylase, protease, esterase, lipase, acid phosphatase, alkaline phosphatase peroxidase, deoxyribonuclease or ribonuclease. Immunoreactivity of pancreas-specific antigen was sensitive to proteolytic enzymes, perchloric acid and high temperature (70 degrees C, 10 min); but insensitive to neuraminidase or beta-glucosidase. Immunohistochemical staining revealed that pancreas-specific antigen was located in acinar cells of human pancreas. In addition, a higher concentration of pancreas-specific antigen was detected in pancreatic juice than in the saline extract of pancreas. This newly identified pancreas-specific antigen, therefore, may be a useful marker protein in physiological studies of pancreas and pancreatic secretion.
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PMID:Purification and characterization of a human pancreas-specific antigen. 678 69

Homogenates of human pancreas in saline were centrifuged at 27 000 X g and the supernates were fractionated by preparative polyacrylamide gel electrophoresis. The gels were divided into sections and each section was injected into rabbits; after absorption with polymerized serum from apparently normal humans, the antiserum obtained by injecting one of the sections was tested against a variety of human tissue extracts but reacted only with saline extracts of human pancreas. The absorbed antiserum, polymerized and made insoluble with glutaraldehyde, was used to purify a pancreas-specific antigen by immunoaffinity batch technique. The purified antigen proved to be a protein with some carbohydrate content (180 mg/g by weight) and a molecular mass of about 2.25 X 10(5) daltons. The antigen is relatively thermostable, and precipitates in the range of 245.64-340.2 g/L saturated ammonium sulfate; its antigenic activity is not affected by incubation with ribonuclease or deoxyribonuclease, but is destroyed by incubation with trypsin or neuraminidase and by extraction with perchloric acid. Immunofluorescence studies show that the antigen is diffusely present in the cytoplasm of pancreatic acinar cells.
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PMID:Isolation and characterization of a human pancreas-specific protein. 698 12

Circulating M antigen, specific for genus Schistosoma, was previously described in serum, urine, patients' milk, and in serum and urine of animals infected by S. mansoni. The M antigen was thermostable and soluble in trichloroacetic acid. It was not hydrolyzed by protease, ribonuclease, amylase, or neuraminidase but destroyed by sodium metaperiodate. In the present study, we have purified the M ag by using trichloroacetic acid solubility, DEAE Sephadex, and immunoadsorption. The M ag showed a neutral electric charge, a m.w. heterogeneity, and was only stained by periodic acid-Schiff. The composition study revealed M ag was a glycoprotein with a polysaccharide moiety (63% of the molecules) particularly rich in galactose, fucose, glucosamine, and mannose, and with a high molecular ratio of serine and threonine. The presence of O-glycosidic linkage allowed M ag to be considered as a mucin or a mucus glycoprotein-like component. It was localized in the cell wall of the gut of adult worms.
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PMID:Purification, immunochemical, and biologic characterization of the Schistosoma circulating M antigen. 698 17

The two major ribonuclease (EC 3.1.27.5) present in normal human urine have been highly purified and extensively characterized for their enzymatic, physical, chemical and structural properties. One of the enzymes, RNAase C, is a glycoprotein which exhibits a pH optimum of 8.5 with RNA as the substrate and preferentially degrades the synthetic homoribopolymer poly(C). This enzyme is resolved into multiple components by column electrofocusing. However, prior treatment with neuraminidase results in a single form of RNAase C with an isoelectric point of 10.4, indicating that the charge heterogeneity is the result of variability in sialic acid content. Amino acid composition and NH2- and COOH-terminal sequence analyses of RNAase C show that this enzyme is very similar to mammalian pancreatic RNAases; the data indicate a peptide chain of 126 amino acid residues and a 33% carbohydrate content. The second enzyme isolated from urine, termed RNAase U, is also a glycoprotein which has a pH optimum of 7.0 with RNA as substrate and is virtually inactive against poly(C). RNAase U lacks sialic acid and focuses as a single component with a highly basic isoelectric point of greater than pH 11.0. The NH2- and COOH-terminal sequences of RNAase U show little homology with the pancreatic RNAases. However, the amino acid composition of this enzyme indicates it is very similar to human spleen RNAase.
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PMID:Purification and properties of ribonucleases from human urine. 721 38


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