Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound   Target Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound

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Query: EC:3.1.27.1 (RNase)
16,360 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The molecules occurring as terminal residues on the external surfaces of nuclei prepared from rat liver by either sucrose-CaCl(2) or citric acid methods and nucleoli derived from the sucrose-CaCl(2) nuclei were studied chemically and electrokinetically. In 0.0145 M NaCl, 4.5% sorbitol, and 0.6 mM NaHCO(3) with pH 7.2 +/- 0.1 at 25 degrees C, the sucrose-CaCl(2) nuclei had an electrophoretic mobility of -1.92 microm/s/V/cm, the citric acid nuclei, -1.63 microm/s/V/cm, and the nucleoli, -2.53 microm/s/V/cm. The citric acid nuclei and the nucleoli contained no measurable sialic acid. The sucrose-CaCl(2) nuclei contained 0.7 nmol of sialic acid/mg nuclear protein; this was essentially located in the nuclear envelope. Treatment of these nuclei with 50 microg neuraminidase/mg protein resulted in release of 0.63 nmol of sialic acid/mg nuclear protein; treatment with 1 % trypsin caused release of 0.39 nmol of the sialic acid/mg nuclear protein. The pH-mobility curves for the particles indicated the sucrose-CaCl(2) nuclei surface had an acid-dissociable group of pK. approximately 2.7 while the pK for the nucleoli was considerably lower. Nucleoli treated with 50 microg neuraminidase/mg particle protein had a mobility of -2.53 microm/s/V/cm while sucrose-CaCl(2) nuclei similarly treated had a mobility of -1.41 microm/s/V/cm. Hyaluronidase at 50 microg/mg protein had no effect on nucleoli mobility but decreased the sucrose-CaCl(2) nuclei mobility to -1.79 microm/s/V/cm. Trypsin at 1 % elevated the electrophoretic mobility of the sucrose-CaCl(2) nuclei slightly but decreased the mobility of the nucleoli to -2.09 microm/s/V/cm. DNase at 50 microg/mg protein had no effect on the mobility of the isolated sucrose-CaCl(2) nuclei but decreased the electrophoretic mobility of the nucleoli to -1.21 microm/s/V/cm. RNase at 50 microg/mg protein also had no effect on the electrophoretic mobility of the sucrose-CaCl(2) nuclei but decreased the nucleoli mobility to -2.10 microm/s/V/cm. Concanavalin A at 50 microg/mg protein did not alter the nucleoli electrophoretic mobility but decreased the sucrose-CaCl(2) nuclei electrophoretic mobility to -1.64 microm/s/V/cm. The results are interpreted to mean that the sucrose-CaCl(2) nuclear external surface contains terminal sialic acid residues in trypsin-sensitive glycoproteins, contains small amounts of hyaluronic acid, is completely devoid of nucleic acids, and binds concanavalin A. The nucleolus surface is interpreted to contain a complex made up of protein, RNA, and primarily DNA, to be devoid of sialic acid and hyaluronic acid, and not to bind concanavalin A.
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PMID:Molecules at the external nuclear surface. Sialic acid of nuclear membranes and electrophoretic mobility of isolated nuclei and nucleoli. 476 32

Synaptic vesicles isolated from guinea-pig cerebral cortex had an electrophoretic mobility of -3.55mum.s(-1).V(-1).cm in saline-sorbitol, pH7.2, at 25 degrees C (ionic strength 0.015g-ions/1). The mobility was pH-dependent, varied with ionic strength and indicated that the vesicular surface contained weak acidic functions with a pK(a) in the range 3.0-3.8. Although the vesicular surface was determined to be highly negatively charged, treatment with neuraminidase had no effect on mobility and indicated that the relatively strong carboxyl groups of sialic acid do not contribute significantly to vesicular electrokinetic properties. Treatment of synaptic vesicles with trypsin or trypsinized concanavalin A resulted in increases in mobility, but treatment with ribonuclease, deoxyribonuclease, chrondroitinase ABC or hyaluronidase had no significant effect on mobility. Mn(2+) or Ca(2+) was more effective in decreasing vesicle mobility than was Mg(2+), Sr(2+) or Ba(2+). The electrokinetic properties of the synaptic vesicle surface are discussed and contrasted with the properties of the synaptosomal membrane.
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PMID:Electrokinetic properties of isolated cerebral-cortex synaptic vesicles. 478 38

Osteoclast-activating factor (OAF) is a soluble mediator found in supernates of human peripheral leukocytes which have been cultured with antigens or phytomitogens. OAF is a potent stimulator of osteoclastic resorption of fetal bone in organ culture. The present studies were designed to characterize OAF chemically. Bone resorbing activity from supernates of leukocytes cultured without added plasma was not lost on dialysis using a membrane with a molecular weight cutoff of 3,500, but was lost when heated to 60 degrees C for 30 min. The activity was lost after treatment with trypsin or pronase but not after treatment with ribonuclease or neuraminidase. Papain, which inactivated parathyroid hormone at a concentration of 25 mug/ml, did not inactivate OAF at 250 mug/ml. OAF did not react with an antibody to bovine parathyroid hormone which cross-reacts with human parathyroid hormone. OAF was also distinguished from active metabolites of vitamin D and from prostaglandin by extraction procedures and immunoassay for prostaglandin E(2). When the medium from activated leukocytes cultured with autologous plasma was fractionated by gel filtration on Sephadex, bone resorbing activity eluated both with plasma proteins and in lower molecular weight fractions. However, when medium from leukocytes cultured without added plasma was chromatographed, all the OAF activity was eluted in a sharp low molecular weight peak located between chymotrypsinogen (25,000 molecular weight) and ribonuclease A (13,700 molecular weight). This peak contained about 4% of the total protein originally present in the supernate. Its activity was destroyed by overnight incubation at 37 degrees C at pH 6 or 8, but not at pH 7.2. After incubation at 4 degrees C, the activity was lost at pH 3 or 10, but not at pH 4-9. The active fraction from Sephadex G-100 was therefore chromatographed at pH 7.2 on DEAE cellulose and carboxymethyl cellulose. The active material was not adsorbed; however, about sevenfold further purification was achieved by removal of contaminants. The material obtained after sequential Sephadex, DEAE and, carboxymethyl cellulose chromatography stimulated resorption of fetal rat bone in culture at concentrations of 0.75-3 mug protein/ml, indicating that this preparation of OAF was nearly as potent as bovine parathyroid hormone in this system.
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PMID:Partial purification of osteoclast-activating factor from phytohemagglutinin-stimulated human leukocytes. 482 37

This paper reports the isolation and characterization of a soluble antigen shared by the liver and kidney of human and some other animal species. Homogenates of human liver in saline were centrifugated at 27,000 g and the supernatants were fractionated by preparative polyacrylamide gel electrophoresis. The gels were divided in sections and each was injected into rabbits; after absorption with polymerized normal human serum, the antiserum obtained by injecting one of the sections reacted only with saline extracts of human liver and kidney when tested against a variety of human tissue extracts. The absorbed antiserum, polymerized and insolubilized with glutaraldehyde, was used to purify the antigen by affinity chromatography. The purified antigen proved to be a glycoprotein containing 19 percent carbohydrate, had a molecular weight of 5.8-6.0 x 10(4) Daltons and a pI of 7.2-7.4. The antigen, relatively thermostable, was precipitated by 35-55 percent ammonium sulphate; its antigenic activity was not affected by extraction with 0.6 N perchloric acid or by incubation with ribonuclease, deoxyribonuclease or neuraminidase but was destroyed by incubation with ttypsin or chymotrypsin. Immunoperoxidase studies showed that the antigen appeared concentrated in the neclei of liver and kidney glomerular epithelial and tubular epithelial cells in humans and rats. The antigen could not be detected in human hepatomas or hypernephromas or in the rat Morris hepatoma 5123.
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PMID:Isolation and characterization of a human liver and kidney-specific protein: the hepato-renal (H-R) antigen. 615 31

A cell suspension derived from a single murine spontaneous mammary adenocarcinoma was resolved on a linear gradient of Ficoll, into twelve distinct neoplastic cell subpopulation. A second cell suspension, also derived from a single murine mammary adenocarcinoma was first treated with vibrio cholera neuraminidase (VCN) then was resolved on an identical gradient of Ficoll into twelve distinct subpopulation. Each cell population was seeded and allowed to proliferate. The cell subpopulations differed in their doubling time, cloning efficiency, tumorigenicity and metastatic capacity. Although in vivo the murine spontaneous mammary adenocarcinoma (SMMAdCa) never metastasized, SMMAdCa-10 subpopulation metastasized into lymph nodes and lungs. All VCN-modified subpopulations were non-oncogenic. Cells from each population were used to immunize groups of syngeneic mice. The spleens of each group were pooled and Immune-RNA's were extracted with the phenol-water standard technique. The IRNA's preparations stimulated DNA synthesis in normal murine spleenocytes. The various I-RNA's differed in their biological activities, base composition and their sensitivity to ribonuclease.
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PMID:Enzymically-mediated changes in murine mammary adenocarcinoma cell membrane induces changes in lymphoid tissue immune ribonucleic acids. 616 33

Human seminal fluid, at low dilutions, prevented the binding of aggregated human IgG (AHG) to bull spermatozoa. Seminal fluids from vasectomized men were also inhibitory. Preincubation of the seminal fluid with the spermatozoa prior to washing and addition to AHG had no inhibitory effect, indicating that the fluid component was reacting directly with AHG. Human seminal fluid was fractionated by gel exclusion chromatography on Ultrogel AcA-34, and AHG inhibitory activity was found in fractions corresponding to a molecular weight of 94,000. The activity in this fraction was stable to boiling for 10 min. It was sensitive to pronase but resistant to glycosidase, phospholipase C, neuraminidase, ribonuclease, and deoxyribonuclease, indicating that it was a protein. The gel filtration fraction readily bound recrystallized Fc and AHG; IgG was bound to a lesser extent, and no reactivity was observed with F(ab')2, IgA, or IgM. Thus, the seminal fluid fraction appeared to specifically react with the Fc portion of IgG. The seminal fluid Fc-binding protein was isolated by affinity chromatography on Fc coupled to CNBr-activated Sepharose 4B. Scatchard analysis revealed that the binding of the seminal fluid Fc-binding protein to recrystallized Fc is reversible and had a Kd of approximately 3 x 10(-6) M.
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PMID:An IgG-Fc binding protein in seminal fluid. 622 60

A specific binding site for somatotropin was solubilized by 1% (v/v) Triton X-100 from a crude particulate membrane fraction of pregnant rabbit liver, partially purified and characterized. The solubilized binding site retained many of the characteristics observed in the original particulate fraction, indicating that extraction of the binding site with Triton X-100 does not cause any major changes in its properties. The binding of human 125I-labelled-somatotropin to the solubilized binding site is a saturable and reversible process, depending on temperature, incubation time, pH and ionic environment. Analysis of the kinetic data revealed a finite number of binding sites with an affinity constant of 0.32 x 10(10)M-1. The binding activity for human 125I-labelled-somatotropin was adsorbed to a concanavalin-A-Sepharose column and was dissociated from the column with alpha-methyl-D-glucoside, suggesting that the binding protein may be a glycoprotein. Using affinity chromatography on concanavalin-A-Sepharose, ion-exchange chromatography on DEAE-cellulose and gel filtration on Sepharose 6B, the binding protein was purified 1000-4000-fold from the original liver homogenate. When the partially purified preparation was chromatographed on Sepharose 6B, the binding protein eluted as a molecule with an apparent molecular weight of 200000, with a Stokes' radius of 4.9 nm. Sucrose-density-gradient centrifugation of the preparation showed that the sedimentation coefficient of the binding protein was 7.2S. Isoelectric focusing experiments revealed that a major part of the protein has an acidic pI (4.2-4.5). Exposure of the protein to trypsin decreased the binding activity for human 125I-labelled-somatotropin or bovine 125I-labelled-somatotropin, whereas ribonuclease, deoxyribonuclease, phospholipase C or neuraminidase had little or no effect.
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PMID:Characteristics of solubilized human-somatotropin-binding protein from the liver of pregnant rabbits. 624 70

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


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