Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:2.7.7.6 (RNA polymerase)
 34,946 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Deoxyribonucleic acid (DNA)-dependent ribonucleic acid (RNA) polymerase activity was assayed on nuclear preparations of chick embryo fibroblast cells at various times after infection with an influenza A virus (fowl plague virus) and was compared with the activity of uninfected cells. Polymerase activity was increased by about 60% by 2 hr after infection, and this increase coincided with an increase in RNA synthesis in infected cells, as determined by pulse-labeling with uridine. No difference could be detected between the polymerases of infected and uninfected cells as to their requirements for DNA primer, divalent cations, and nucleoside triphosphates, and they were equally sensitive to addition of actinomycin D to the reaction mixture. It is possible that host cell DNA-dependent RNA polymerase is involved in the replication of influenza virus RNA.
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PMID:Deoxyribonucleic acid-dependent ribonucleic acid polymerase activity in cells infected with influenza virus. 574 27

Reich, Paul R. (National Institutes of Health, Bethesda, Md.), Norman L. Somerson, James A. Rose, and Sherman M. Weissman. Genetic relatedness among mycoplasmas as determined by nucleic acid homology. J. Bacteriol. 91:153-160. 1966.-A sensitive membrane filter method to detect nucleic acid homology was used to determine genetic relatedness among mycoplasma isolates. Deoxyribonucleic acid (DNA) was isolated from mycoplasmas and used as a primer for synthesis of tritium-labeled, complementary ribonucleic acid (RNA) by the enzyme RNA polymerase. DNA from each mycoplasma isolate tested was reacted separately with complementary RNA synthesized with homologous or heterologous DNA as primer. The quantity of DNA-RNA hybrids formed was assayed by the nitrocellulose membrane filter method. The amount of radioactivity bound to the membrane filter was used to measure the degree of homology between the nucleic acids. The three mycoplasma isolates from human oral cavities (DC 63, V2785, Botteicher) and the prototype strain PG21 placed in the Mycoplasma hominis type 1 group by gel diffusion and complement-fixation testing were investigated with this technique. Analysis of the data confirmed their immunological grouping with the M. hominis type 1 and their distinction from other human mycoplasmas. In contrast to the data from immunological studies, none of the four isolates tested appeared to be identical to any other. Preliminary experiments with DNA from four other mycoplasma isolates from tissue cultures inoculated with human material revealed them to be closely related, and possibly identical. The advantages of this nucleic acid homology technique for the study of relatedness among mycoplasmas are described.
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PMID:Genetic relatedness among mycoplasmas as determined by nucleic acid homology. 590 90

The recognition sites for several restriction endonucleases were mapped within deoxyribonucleic acid coding for histidine utilization (hut) genes of Salmonella typhimurium and Klebsiella aerogenes. Deoxyribonucleic acid fragments containing the two hut promoters were identified by ribonucleic acid polymerase binding.
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PMID:Physical maps of Klebsiella aerogenes and Salmonella typhimurium hut genes. 625 44

Using the promotor-cloning vehicle described by An and Friesen (J. Bacteriol. 140:400-410, 1979), Escherichia coli chromosomal deoxyribonucleic acid fragments derived from the lambda drifd18 transducing phage were cloned in one of several unique restriction endonuclease sites adjacent to tetracycline(tet) genes that lack their own promotor. One of these plasmids has been used to isolate nine variants having mutations that lie in a putative internal promoter which is located between rplL and rpoB. Deoxyribonucleic acid sequence analysis revealed that, in all nine mutants, a single base change, C to T, in the ribonucleic acid polymerase recognition site led to a large increase in promoter activity. Analysis of a variety of plasmids in which tet is fused to various promoters yielded the following results: (i) rplK and rplA, genes for ribosomal protein L11 and L1, respectively, were cotranscribed from a common promoter located upstream from rplK; (ii) there was a strong promoter in the region between the rplKA operon and rplJ, the gene for ribosomal protein L10; (iii) an attenuator region was located between rplL, the gene for ribosomal protein L12, and rpoB, the gene for ribonucleic acid polymerase subunit beta; (iv) transcription terminated immediately after rpoC, the gene for ribonucleic acid polymerase subunit beta'; (v) a gene coding for unknown protein U, which is located between tufB and the rplKA operon, had its own promoter; (vi) the tufB gene was separated from all of the genes described above and had its own promoter.
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PMID:Characterization of promoter-cloning plasmids: analysis of operon structure in the rif region of Escherichia coli and isolation of an enhanced internal promoter mutant. 700 14


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