Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.1.27.5 (RNase)
 17,967 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Cell walls isolated from competent streptococci (group H strain Challis) were shown to bind more homologous and heterologous deoxyribonucleic acid (DNA) than noncompetent walls. Heat- and alkali-denatured DNA was not bound by either wall preparation. Pretreatment of cell walls with cetyltrimethylammonium bromide sharply increased the binding of DNA but did not increase transformation of whole cells. Pretreatment of the walls with either sodium dodecylsulfate, deoxyribonuclease and ribonuclease, or with crude competence-provoking factor did not affect the binding of DNA. Antiserum prepared against whole competent cells completely blocked transformation and also inhibited DNA binding to competent cell walls. Adsorption of this antiserum with competent Challis cells removed its blocking action for both binding and transformation. Pretreatment of walls with trypsin and Pronase destroyed their ability to bind DNA. Trypsin treatment also blocked transformation in whole cells. The transforming activity of DNA bound to cell walls was found to be protected from deoxyribonuclease action. Significant differences were observed in the arginine, proline, and phenylalanine content of competent and noncompetent walls. With few exceptions, the amino acids released from competent cell walls by trypsin were several-fold greater than from noncompetent walls. The results indicate that (i) two binding sites exist, one in competent cells only and essential for subsequent transformation, and a second, present in all cells, which is not involved in transformation; (ii) both sites are protein in nature; (iii) the transformation site is blocked by antibody; and (iv) the competent cell wall possesses tryptic-sensitive protein not present in the noncompetent wall.
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PMID:Binding of deoxyribonucleic acid by cell walls of transformable and nontransformable streptococci. 510 95

Zeya, H. I. (University of North Carolina, Chapel Hill), and J. K. Spitznagel. Cationic proteins of polymorphonuclear leukocyte lysosomes. I. Resolution of antibacterial and enzymatic activities. J. Bacteriol. 91:750-754. 1966.-A lysosomal fraction from polymorphonuclear (PMN) leukocytes of guinea pig peritoneal exudate was subjected directly to electrophoresis on cellulose acetate paper treated with cetyltrimethyl ammonium bromide. The Iysosomal components resolved into seven bands moving towards the cathode. Assay of the eluted bands showed that the antibacterial activity was distinct from lysosomal enzymes and was associated with three cationic components (bands I, II, and III) which migrated most rapidly towards the cathode, ahead of lysozyme ribonuclease and deoxyribonuclease. Qualitatively, the antibacterial components appeared to be rich in arginine. The antibacterial components were absent in the pherograms of nuclear fractions of PMN leukocytes and in supernatant fractions that remained after lysosomes were removed from cell homogenates by centrifugation at 8,000 x g.
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PMID:Cationic proteins of polymorphonuclear leukocyte lysosomes. I. Resolution of antibacterial and enzymatic activities. 593 73

This paper presents an analysis of the protective properties of the components in ribonuclease (RNase)-sensitive ribosomal vaccines, in particular the ribonucleic acid (RNA). The protective activities in mice of purified ribosomes derived from Pseudomonas aeruginosa and from Listeria monocytogenes were compared. Both ribosomal vaccines had to be combined with the adjuvant dimethyldioctadecylammonium bromide (DDA) in order to be protective, and both lost their activity after RNase treatment. The ribosomal vaccines as well as RNA purified from the ribosomes induced non-specific protection. Intraperitoneal injection of RNA with DDA induced an influx of peritoneal cells. Furthermore, RNA with DDA activated macrophages as shown by, a.o., enhanced phagocytic activity and killing capacity for L. monocytogenes. The results suggest that the observed macrophage activation is probably T-cell-independent. With regard to the ribosomal vaccine of P. aeruginosa it is concluded that RNA also contributed to the protective activity by increasing the humoral response against suboptimal concentrations of contaminating cell surface antigens. In conclusion, it is proposed that ribosomal vaccines may be considered as a combination of a non-specific immunomodulator (RNA) with pathogen-specific cell surface antigens. This concept of ribosomal vaccines is discussed in relation to the literature concerning RNase-sensitive ribosomal vaccines.
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PMID:Ribonuclease-sensitive ribosomal vaccines. 608 81

In mice, active protection against Pseudomonas aeruginosa could be induced with two fractions derived from a crude preparation of ribosomes from P. aeruginosa. The two fractions were obtained by gel filtration chromatography of the crude ribosomal preparation on Sepharose CL-2B. In fraction I, less than 1% of the ribonucleic acid (RNA) applied to the column was recovered. Fraction II contained RNA and protein in a ratio of 1.94. The presence of ribosomes in this fraction was confirmed by analysis on a sucrose density gradient. The protection by fraction I was not affected by treatment with ribonuclease; in contrast, incubation of fraction II with ribonuclease completely abolished active protection. Fraction I contained lipopolysaccharide (LPS) as was indicated by the presence of 2-keto-3-deoxyoctonic acid. No LPS was found in fraction II. The adjuvant dimethyl dioctadecyl ammonium bromide enhanced the protection by fraction II; however, immunity by a low dose of fraction I was abolished by dimethyl dioctadecyl ammonium bromide. Protection by fractions I and II appeared to be restricted to the homologous serotype of P. aeruginosa. These results indicate that RNA is required for protection by fraction II. Active protection by fraction I is likely due to LPS.
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PMID:Ribonuclease-sensitive ribosomal vaccine of Pseudomonas aeruginosa. 615 37

The phenanthridinium dye, ethidium bromide (EB), selectively intercalates into double-stranded regions of nucleic acids with a large and specific increase in fluorescence. When used for the staining of fixed tissue sections, the dye stains cellular nuclei with excellent resolution of microscopic detail. In some fixed tissues, particularly pancreatic acini, cytoplasm stains intensely and this staining can be abolished by digestion with trypsin and ribonuclease. The orange fluorescence of EB can be easily distinguished from the green fluorescence of fluorescein and EB is thus an excellent counterstain for immunofluorescence. Ethidium bromide is a useful and practical stain for the fluorescence microscopy of tissue sections and, in combination with enzymatic digestion of RNA, provides a simple way to differentially localize DNA and RNA.
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PMID:Ethidium bromide: a nucleic acid stain for tissue section. 616 60

Techniques utilizing Feulgen, azure B bromide, methyl green-pyronin, gallocyanin chromalum and cresyl violet stains have been modified and adapted for visualizing nucleic acids in 0.5-2.0 micrometer sections of tissues embedded in glycol methacrylate (GMA). Methods for evaluating the stain specificity for DNA and RNA using deoxyribonuclease and ribonuclease digestions, aldehyde blocking, and acid extractions are also described. The specificity of the stains in GMA embedded tissues is comparable to that reported for paraffin-embedded tissues.
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PMID:Glycol methacrylate in light microscopy: nucleic acid cytochemistry. 616 20

Nuclear matrix was prepared by sequential treatment of oviduct nuclei with Triton X-100, DNase I, and 2 M NaCl. Published procedures were modified such that as many steps as possible were performed at -20 degrees C to minimize endogenous ribonuclease activity. Examination of electron micrographs confirmed the isolation of intact nuclear matrix structures. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis of the proteins in these structures showed an absence of histones and an enrichment of certain nonhistone proteins. RNA was isolated from the nuclear matrix preparations and subjected to denaturing gel electrophoresis. Gels were analyzed by ethidium bromide staining and by hybridization of Northern blots to cloned DNA probes for ovalbumin, ovomucoid, 5.8S ribosomal RNA, and U1 RNA. All of the precursors to ovalbumin and ovomucoid mRNAs (including various splicing intermediates) and all of the precursors to ribosomal RNA were associated exclusively with the nuclear matrix fraction. By contrast, mature ovalbumin and ovomucoid mRNAs were distributed between matrix and nonmatrix fractions. These observations were further supported by quantitative hybridization analysis of the RNA in nuclear and matrix fractions. It was found that less than 50% of the mature message of intact nuclei was recovered in the matrix, while most significantly, over 95% of the mRNA precursors remained associated with the matrix. Finally, mature ribosomal RNAs and virtually all of the small nuclear RNAs (including U1 RNA) were also distributed between matrix and nonmatrix fractions. Our results suggest that all precursor RNAs (be they precursors to mRNA or rRNA) are exclusively associated with the nuclear matrix and support the notion that the nuclear matrix may be the structural site for RNA processing within the nuclei of eucaryotic cells.
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PMID:Ribonucleic acid precursors are associated with the chick oviduct nuclear matrix. 618 7

Intact and fast-sedimenting nucleoids of Bacillus licheniformis were isolated under low-salt conditions and without addition of detergents, polyamines or Mg2+. These nucleoids were partially unfolded by treatment with RNase and completely unfolded by treatments that disrupt protein-DNA interactions, like incubation with proteinase K, 0.1% sodium dodecyl sulphate and high ionic strength. Ethidium bromide intercalation studies on RNase-treated, proteinase-K-treated and non-treated nucleoids in combination with sedimentation analysis of DNase-I-treated nucleoids revealed that DNA is organized in independent, negatively supertwisted domains. In contrast to the DNA organization in bacterial nucleoids, isolated under high-salt conditions and in the presence of detergents (Stonington & Pettijohn, 1971; Worcel & Burgi, 1972), the domains of supertwisted DNA in the low-salt-isolated nucleoids studied here are restrained by protein-DNA interactions. A major role for nascent RNA in restraining supertwisted DNA was not observed. The superhelix density of B. licheniformis nucleoids calculated from the change of the sedimentation coefficient upon ethidium bromide intercalation, was of the same order of magnitude as that of other bacterial nucleoids and eukaryotic chromosomes, isolated under high-salt conditions: namely, -0.150 (corrected to standard conditions: 0.2 M-NaCl, 37 degrees C; Bauer, 1978). Electron microscopy of spread nucleoids showed relaxed DNA and regions of condensed DNA. Spreading in the presence of 100 micrograms ethidium bromide per ml revealed only condensed structures, indicating that nucleoids are intact. From spreadings of proteinase-K-treated nucleoids we infer that supertwisted DNA and the protein-DNA interactions, responsible for restraining the superhelical DNA conformation, are localized in the regions of condensed DNA.
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PMID:Folding of prokaryotic DNA. Isolation and characterization of nucleoids from Bacillus licheniformis. 618 37

To investigate the binding of a nitrofuran to tissue macromolecules in vivo, the urinary bladder carcinogen N-[4-(5-nitro-2-furyl)- 2-[35S]thiazolyl]formamide [[35S]FANFT; 94 mCi/mmol] was given p.o. to conventional [n = 4; 115 +/- 8 g (S.D.)] and germfree [n = 4; 105 + 5 g] female CD rats [1.23 mCi/rat]. After 18 hr, organs were removed, and macromolecules were then isolated from individual livers and kidneys and from pooled urinary bladders. A hydroxylapatite isolation procedure was followed (Beland et al., J. Chromatogr., 174: 177-186, 1979), and the nucleic acids obtained were further purified by digestion with appropriate nucleases and/or centrifugation (105,000 X g). The results are as follows and are given in pairs (conventional/germ-free) expressed as pmol FANFT bound per mg macromolecule. Protein binding levels were: liver, 165 +/- 40/307 +/- 31; kidney, 72 +/- 19/88 +/- 24; bladder, 272/322. RNA levels were: liver, 217 +/- 184/413 +/- 196; kidney, 219 +/- 60/617 +/- 196; bladder, 448/1373. DNA levels were: liver, 9.8 +/- 7.5/17.0 +/- 7.5; kidney, 0.69 +/- 0.38/4.5 +/- 1.0. The quantity of bladder DNA was insufficient for accurate measurement. Diethylaminoethyl cellulose chromatography of liver RNA from a germfree rat, either before or after RNase digestion, showed that the majority of the radioactivity was associated with a polynucleotide fraction that appeared to be RNase resistant and accounted for only a small portion of the total RNA but that also permitted the intercalation of ethidium bromide. The deformylated FANFT metabolite, 2-amino-4-(5-nitro-2-fury)thiazole, reacted with transfer RNA upon reduction with sodium dithionite in vitro to give adduct(s) that also appeared to be RNase resistant. Thus, these results show that the urinary bladder carcinogen FANFT or its metabolites react in vivo with protein and nucleic acid of both target and nontarget organs and that binding levels are elevated in germfree rats.
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PMID:Enhanced macromolecular binding of N-[4-(5-nitro-2-furyl)-2-thiazolyl]- formamide in germfree versus conventional rats. 619 May 54

The primary structure of human (Homo sapiens) pancreatic ribonuclease has been determined by automatic sequencing of the native protein and by analysis of peptides obtained by cleavage with proteolytic enzymes, cyanogen bromide, and hydroxylamine. The following sequence was deduced: (sequence in text). Human pancreatic ribonuclease differs at 37 positions from bovine pancreatic ribonuclease. In addition the human enzyme has three more residues at the C-terminus. About half of the enzyme molecules contain carbohydrate attached to the sequence Asn-Met-Thr (34-36). Two other Asn-X-Ser/Thr sequences are carbohydrate free. Human pancreatic ribonuclease contains many positively charged residues, especially near the N-terminus, while negatively charged residues are more concentrated near the C-terminus.
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PMID:The amino acid sequence of human pancreatic ribonuclease. 620 Oct 87


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