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)

Polyhedral cytoplasmic deoxyribovirus virions contain a DNA-dependent RNA polymerase which catalyzes the incorporation of ribonucleotides into an acid-precipitable product. Treatment of virions with sodium deoxycholate and dithiothreitol resulted in the formation of subviral particles which could be separated from virions by rate zonal centrifugation in sucrose gradients. Subviral particles were RNA polymerase-positive and more active per unit mass of protein than virions. In vitro enzyme activity associated with subviral particles required addition of ribonucleotides, Mg(2+), and exogenous denatured DNA template. Optimal enzyme activity occurred over a broad pH (7.2 to 8.8) and Mg(2+) concentration (2 to 10 mumol) range. The specific activity of the RNA polymerase was maximal at 37 C. Addition of DNase or actinomycin D to the reaction mixture reduced the incorporation of [(3)H]UMP into an acid-precipitable product. The product of the reaction was sensitive to degradation by RNase but not to DNase or Pronase. These data suggest that the enzyme copies DNA into RNA.
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PMID:DNA-dependent RNA polymerase activity associated with subviral particles of polyhedral cytoplasmic dexoyribovirus. 485 85

Ribosomal preparations obtained from Salmonella typhimurium by differential centrifugation and sodium dodecyl sulfate (SDS) treatment of the bacillary lysate were found to be immunogenic in F(1) hybrid (C(3)H/HeJ x DBA/2J) and albino Swiss mice, as determined by progressive host survival. The immunity obtained was independent of the need for adjuvant and dependent on the dosage of immunogen given. Immunizations with the ribosomal preparations induced an immune response comparable to that obtained by vaccination with living organisms and significantly greater than that obtained by immunization with heat-killed salmonellae, purified lipopolysaccharide, or crude and SDS-treated endotoxin preparations. No effect on the immunogenicity of the ribosomal fraction was observed by enzymatic treatment with trypsin, Pronase, deoxyribonuclease, and pancreatic ribonuclease. Linear sucrose density gradient resolution of the preparations showed that the immunogenicity of the ribosomal fraction was not unique to any one of its subcomponents. Ethyl alcohol-precipitated, crude ribonucleic acid preparations obtained from the ribosomal and sucrose density-resolved ribosomal preparations were found to induce an immune response comparable to that obtained by immunization with the entire ribosomal fraction. Dialysis in doubly distilled demineralized water slightly reduced the immunogenicity of the preparation; however, comparable dialysis in 10(-4)m MgCl(2)-phosphate buffer did not. Chemical assays of the preparations found to be immunogenic were performed.
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PMID:Isolation and partial characterization of an immunogenic moiety obtained from Salmonella typhimurium. 489 82

Studies were undertaken to find a substance or substances for use in primary binding types of tests to detect humoral antibodies in rabbits and monkeys exposed to the tubercle bacillus that would distinguish between strains of mycobacteria. The antigen employed was a component of the 5159 strain of Mycobacterium tuberculosis that was obtained following sonification, ultracentrifugation, electrophoresis, and elution from a preparative polyacrylamide column. When the antigen was labeled with (131)I, specific binding was observed in sera from immunized rabbits and BCG-protected rhesus monkeys by the radio-gel electrophoresis and ammonium sulfate tests. This component was partially characterized, and its major antigenic determinants were associated with anionic mucopolysaccharides. Electrophoretically at pH 8.3 it migrated anodally to albumin, its molecular weight was between 9,000 and 12,000, and it was soluble in 50% saturated ammonium sulfate. Binding to antibody was destroyed after treatment with Pronase, but not after DNase or RNase. Inhibition of the reaction, as measured by the ammonium sulfate test, between the (131)I-labeled component and antisera from rabbits that had been immunized with sonicated 5159 organisms, was studied. These experiments demonstrated a capacity to define subtle similarities and differences among different mycobacteria and mycobacterial components. Some microorganisms not clearly related to mycobacteria also partially inhibited this reaction, suggesting that they shared antigenic groups with the component derived from 5159 organisms. The studies described suggested the advisability of using direct primary tests and purified components of mycobacteria to differentiate further the antigenic groups between individual pathogenic mycobacteria and between pathogenic and nonpathogenic organisms.
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PMID:Binding between components of the tubercle bacillus and humoral antibodies. 498 14

Rubella virus ribonucleoprotein was accessible to pancreatic ribonuclease, Pronase, and certain polyanions. Most of the ribonucleic acid (RNA) label was made acid-soluble by ribonuclease, whereas Pronase and the polyanions liberated 40S RNA from the ribonucleoprotein.
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PMID:Release of rubella virus ribonucleic acid from ribonucleoprotein by polyanions. 502 96

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

Infectious ribonucleic acids (IRNA) of Venezuelan equine encephalitis and Eastern equine encephalitis viruses were observed to form noninfectious complexes with a basic polyamino acid, poly-l-lysine. Original infectivity was recovered from the complexes by digestion of the polylysine with Pronase, and partial recovery was effected by treatment with sodium dodecyl sulfate. Infectivity could not be recovered from the complexes containing polylysine of 100,000 molecular weight by changes in ionic strength, pH, or by treatment with phenol, deoxycholate, or digitonin. Masking of infectivity by polylysine was demonstrated in vivo as well as by plaque assay in tissue culture. Poly-l-lysine preparations of high molecular weight (44,000 to 100,000) were more effective than low molecular weight (3,000) materials in masking infectivity of IRNA. When complexes, in which infectivity had been masked by low molecular weight polylysine, were suspended in 1 m NaCl, some infectivity was recovered. Complexes of polylysine-IRNA differed from control IRNA alone in (i) resistance to inactivation by ribonuclease, (ii) sedimentation patterns in sucrose gradient centrifugation, and (iii) stability of recoverable infectivity during different physical treatments.
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PMID:Effects of poly-L-lysine on infectious viral nucleic acid. 555 81

In xiphophorine fish suffering from a genetically caused melanoma, both suppression of melanoma development and regression of the existing melanoma were observed after treatment of the fish with an "anti-melanoma immune RNA." This RNA was extracted from the lymphoid organs of guinea pigs immunized with fish melanoma. RNA from guinea pigs immunized with fish skin or liver and RNA from nonimmunized guinea pigs were ineffective. RNase treatment of the anti-melanoma immune RNA diminished its activity, although Pronase treatment did not. Analysis of antisera obtained from guinea pigs and rabbits immunized with either melanoma or normal skin of xiphophorine fish revealed differences in the immune responses induced by these tissues. The anti-melanoma sera recognized antigens in melanoma extracts, which were not present in skin extracts. These antigens were not recognized by the anti-skin sera. The results suggest specificity of the anti-melanoma immune RNA.
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PMID:Suppression of melanoma development and regression of melanoma in xiphophorine fish after treatment with immune RNA. 616 47

A unique DNA-binding protein was detected that inhibited DNA degradation induced by bleomycin and was decreased in sera of cancer patients. The protein from normal human serum was purified to homogeneity by ammonium sulfate precipitation and DEAE-cellulose and DNA-cellulose column chromatography. Two-dimensional isoelectric focusing gel electrophoresis revealed a single protein spot with a molecular weight of 64,000 and a pI at pH 5.9. The NH2 terminus was lysine, and the ratio of acidic to basic residues was 1.2. DNA binding was demonstrated by column chromatography, agarose gel electrophoresis, fluorescence quenching, and circular dichroism. The inhibitory activity was abolished by treatment with Pronase but not by RNase or DNase I. FeCl2 caused a partial loss of inhibitory activity. The inhibition of DNA degradation was more effective for breakage induced by bleomycin than neocarzinostatin, macromomycin, or DNase I. Evidence from DNA-binding studies suggests the inhibition is due to binding of the protein to sites on DNA preferred by bleomycin. Thus, the protein could be useful for studies on the mechanism of action of bleomycin and other antitumor agents, the cytotoxic effects of which are due primarily to damage of cellular DNA. The protein was decreased significantly in sera of cancer patients, and its potential use as a diagnostic tool for neoplasias is being investigated further.
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PMID:Inhibition of PM-2 DNA degradation by a human serum protein. 617 27

The mechanism of poly ADPR synthesis and the transfer of poly ADPR to histone H1 molecule by electrophoretically homogenous calf thymus poly ADPR polymerase containing DNA was examined. 1) An acid insoluble radioactive complex (I) was obtained after incubation of purified enzyme with [3H] NAD. The stability of (I) was examined by SDS-polyacrylamide gel electrophoresis. The complex (I) was stable against acid, SDS, urea, DNase and RNase, but labile against pronase, trypsin, alkali and snake venom phosphodiesterase treatment. The molecular weight of (I) was about 130 000 daltons estimated by SDS-gel electrophoresis. The radioactive products of successive alkali, venom phosphodiesterase and Pronase hydrolysis of (I) were PR-AMP and AMP. The mean chain length of poly ADPR of (I) was 20--30. These results suggest that the complex (I) is poly ADP-ribosylated poly ADPR polymerase. 2) Besides (I), a second radioactive peak (II) was observed when acid insoluble products obtained from an incubation mixture containing purified poly ADPR polymerase, [3H] NAD and purified histone H1 were analyzed on SDS-polyacrylamide gel electrophoresis. The molecular weight of (II) was estimated to be about 23 000 daltons. The complex (II) is eluted like histone H1 on CM-cellulose columns and hydrolyzed by alkali, trypsin and snake venom phosphodiesterase but not by DNase, or RNase. The comples (II) was extracted selectively by 5 per cent perchloric acid or 5 per cent trichloroacetic acid from mixture of (I) and (II). The mean chain length of poly ADPR of complex (II) and 5--20; these results suggest that the complex (II) is poly ADP-ribosylated histone H1. 3) Results 1) and 2) indicate that purified DNA containing, thus DNA independent, poly ADPR polymerase catalyzes two different reactions, the ADPR transfer onto the enzyme itself and onto histone H1 and the elongation of ADPR chains. Dimeric forms of ADP-ribosylated histone H1 was not observed. Free poly ADPR was observed only when very small quantities of enzyme were used for incubation.
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PMID:Adenosine diphosphate ribosylation of histone H1 by purified calf thymus polyadenosine diphosphate ribose polymerase. 624 65

Delayed-type hypersensitivity (DTH) induced with Salmonella typhimurium transfer factor (TF) contributed to an increase in mean survival days of mice challenged with homologous organisms and afforded only a low level of host protection as determined by survival rate, compared with that obtained by active immunization. TF of other enteric bacteria could transfer DTH which is cross-reactive to salmonella antigen but did not afford host protection. Although TF of Listeria monocytogenes did not transfer the cross-reactive DTH, it could confer the significant increase in mean survival days against the lethal challenge with S. typhimurium. Listerial ribosomal vaccine conferred the high level of mouse protection without inducing DTH to salmonella antigen. The resistance generated upon active immunization with listerial ribosomal vaccine could be enhanced by the injection of S. typhimurium TF to the same level as that obtained after immunization with homologous ribosomal vaccine. Among salmonella TF, there could be no cross-reactive immunity between S. typhimurium and S. choleraesuis, although the cross-reactive DTH was observed. The DTH transfer ability of TF was sensitive to Pronase which could not affect the ability to transfer host immunity, but RNase could abolish the ability to transfer host immunity without impairing DTH transfer activity. These results suggest that in mouse typhoid infection, DTH is not associated with host protection as determined by survival rate.
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PMID:Separate transfer of mouse protection and delayed-type hypersensitivity with Salmonella typhimurium transfer factor. 638 Jul 67


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