Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:2.7.7.48 (transcriptase)
 9,479 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

1. Conditions have been established for the estimation of molecular weights of proteins by analytical gel filtration and sucrose-density-gradient centrifugation in 2.5m-potassium chloride-1m-sodium chloride; Halobacterium cutirubrum polynucleotide phosphorylase, DNA-dependent RNA polymerase and RNA-dependent RNA polymerase have been studied by these methods. 2. The RNA-dependent polymerase has also been studied by density-gradient centrifugation in the absence of salt. 3. All three proteins are of unusually low molecular weight compared with similar enzymes from non-halophilic bacteria.
 ...
PMID:Nucleic acid enzymology of extremely halophilic bacteria. Gel-filtration and density-gradient-centrifugation studies of the molecular weights of Halobacterium cutirubrum polynucleotide phosphorylase and deoxyribonucleic acid- and ribonucleic acid-dependent ribonucleic acid polymerases. 511 75

Hantaan virus, the prototype virus of hemorrhagic fever with renal syndrome, was examined for nucleic acid characteristics which would support its previously proposed inclusion in the virus family Bunyaviridae. Nucleocapsid RNA from Hantaan virions and a control bunyavirus were examined for ribonuclease A (RNase A) sensitivity. Both viruses exhibited a similar accessibility of RNA within nucleocapsids to digestion by RNase A. Complete digestion of the RNA of both viruses was affected with high concentrations of ribonuclease. Evidence for negative strand RNA polarity was obtained by an in vitro transcriptase assay. RNA dependent RNA polymerase activity was associated with Hantaan virions. Polymerase activity required manganese and nucleoside triphosphates and was enhanced by magnesium, 2-mercaptoethanol, and sodium chloride. Oligonucleotide map analysis of the large (L), medium (M), and small (S) genome segments of Hantaan virus demonstrated that each RNA species was unique with respect to each other and was different from host cell ribosomal RNA. A common 3' terminal sequence of the three genome segments was determined to be 3' AUCAUCAUCUG. This sequence is different from those reported for viruses within the four recognized genera of the Bunyaviridae. Because all other data were consistent with nucleic acid characteristics of the Bunyaviridae, we propose a separate genus within the Bunyaviridae with Hantaan as its prototype virs.
 ...
PMID:Analysis of Hantaan virus RNA: evidence for a new genus of bunyaviridae. 641 60

Part of the RNA synthesized from nucleoside triphosphate precursors by partially purified RNA synthetase, an enzyme induced in Escherichia coli by the RNA-containing phage MS 2, is resistant to hydrolysis by ribonuclease. Upon heating in 0.15M sodium chloride, 0.015M sodium citrate followed by fast cooling the material becomes ribonuclease-sensitive with a sharp transition at 102 degrees to 104 degrees C. The suggestion that the ribonuclease-resistant product is double-stranded RNA is reinforced by restoration of the ribonuclease resistance of the heat-denatured material by reannealing at temperatures just below the transition point and by its buoyant density in cesium sulfate. It is suggested that double-stranded RNA is the replicative form of MS 2 phage RNA.
 ...
PMID:DOUBLE-STRANDED RIBONUCLEIC ACID FORMATION IN VITRO BY MS 2 PHAGE-INDUCED RNA SYNTHETASE. 1406 44

Hepatitis A virus (HAV) strains found in selected South African (SA) surface waters were characterised to establish what HAV types are circulating in the environment, thus reflecting circulation in the surrounding communities. Surface water samples used for irrigation or domestic purposes, and water samples from the outflow of wastewater plants were collected from six provinces. Viruses were recovered from the samples using a glass wool adsorption-elution method and then further concentrated using polyethylene glycol/sodium chloride precipitation. After automated nucleic acid extraction, samples were analysed for HAV by real-time reverse-transcriptase polymerase chain reaction. HAV strains were genotyped by nucleotide sequence analysis of the capsid gene VP1 and the VP1/P2B junction. HAVs were detected in 76% (16/21) of the surface water samples and in 37% (19/51) of the samples from the wastewater plants. Strains were characterised from 32 of the 35 samples and classified within genotype IB. The presence of genotype IB in the water sources confirms human faecal contamination. Hence, these faecally-contaminated water sources may be a potential transmission route of HAV infection and a potential source of contamination of irrigated fresh produce in SA.
...
PMID:Molecular characterisation of hepatitis A virus strains from water sources in South Africa. 2462 38