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:2.7.7.6 (RNA polymerase)
34,946 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Cold-sensitive restriction of Pseudomonas phage CB3 by Pseudomonas aeruginosa strain PAT2 involves some aspect of CB3 specific RNA synthesis at 20 C. Experiments using chloramphenicol treatment and RNA-DNA hybridization establish that the amount of CB3 RNA present at 20 C is consistent with the known percentage of phage yielder cells at 20 C. Thus, it appears that nonyielder cells of PAT2 synthesize little or no phage-specific mRNA. Burgess technique extracted PAT2 RNA polymerase (RNAP) is cold sensitive when assayed in vitro with CB3 DNA at 20 C. However, it is not cold sensitive when either calf thymus or PAT2 DNA are the templates for transcription. Low ionic strength assay conditions eliminate the cold sensitivity of PAT2 RNAP. The effect of low ionic environments on transcription initiation along with the in vivo and in vitro suppression of cold sensitivity by host rifampin resistance suggests that the inability of CB3 to reproduce in PAT2 at 20 C is a cold-sensitive step in host RNAP initiation. Our modified RNAP extraction procedure for PAT2 and PAO1C also results in the recovery of cold-sensitive PAT2 RNAP with respect to CB3 DNA templates and points to basic enzymological differences between the two hosts. A model is presented for the unusual influence of temperature on the initiation process of both PAT2 and PAO1C on RNAP transcription.
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PMID:Cold-sensitive Pseudomonas RNA polymerase. II. Cold-promoted restriction of bacteriophage CB3 and the lack of host-dependent bacteriophage-specific RNA transcription. 420 18

Deoxyribonucleic acid-dependent ribonucleic acid (RNA) polymerase (EC 2.7.7.6) was purified from the dimorphic bacterium Caulobacter crescentus at three stages in development. Enzyme from pure populations of stalked cells, as well as populations enriched in swarmer and predivisional cells, appeared identical in subunit structure and template requirements. The molecular weights of the enzyme subunits were 165,000, 155,000, 101,000, and 44,000, respectively. By analogy with RNA polymerase from other bacterial sources, they are considered to be components of the C. crescentus holoenzyme, beta', beta, sigma, and alpha, respectively. The C. crescentus enzyme appeared similar to the Pseudomonas aeruginosa enzyme and unlike the Escherichia coli enzyme with respect to subunit molecular weights and failure to separate into core and sigma components upon phosphocellulose chromatography. In addition, the effects of ionic strength on the time course of polymerization varied both with the sources of bacterial polymerase and bacteriophage DNA.
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PMID:Deoxyribonucleic acid-dependent ribonucleic acid polymerase of Caulobacter crescentus. 473 61

Syringomycin, a wide-spectrum antibiotic produced by strains of Pseudomonas syringae which cause bacterial canker of peach, was able to bind to salmon sperm and calf thymus deoxyribonucleic acid but not to calf thymus histone; it also inhibited ribonucleic acid polymerase activity. These abilities to bind to deoxyribonucleic acid and to inhibit ribonucleic acid polymerase were inactivated when the phytotoxic and antibiotic properties of syringomycin were inactivated.
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PMID:The influence of syringomycin on ribonucleic acid synthesis. 581 86

We have developed two procedures which allow the very rapid purification of glutamine synthetase (GS) from a diverse variety of bacteria. The first procedure, based upon differential sedimentation, depends upon the association of GS with deoxyribonucleic acid in cell extracts. The second procedure, derived from the method of C. Gross et al (J. Bacteriol. 128:382-389, 1976) for purifying ribonucleic acid polymerase by polyethylene glycol (PEG) precipitation, enabled us to obtain high yields of GS from either small or large quantities of cells. We used the PEG procedure to purify GS from Klebsiella aerogenes, K. pneumoniae, Escherichia coli, Salmonella typhimurium, Rhizobium sp. strain 32H1, R. meliloti, Azotobacter vinelandii, Pseudomonas putida, Caulobacter crescentus, and Rhodopseudomonas capsulata. The purity of the GS obtained, judged by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, was high, and in many instances only a single protein band was detected.
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PMID:Purification of glutamine synthetase from a variety of bacteria. 610 84

The xylABC operon on the TOL plasmid directs the synthesis of enzymes for conversion of toluene to benzoate and is positively controlled by the regulatory gene xylR. In the study here the nucleotide sequence was determined for the regulatory region of this operon. The in vivo transcription initiation site of the operon was determined by S1 nuclease and reverse transcriptase mapping. RNA was prepared from m-methylbenzyl alcohol-induced cells of Pseudomonas putida and Escherichia coli carrying pTN2, a derivative of the TOL plasmid containing the structural and regulatory genes of the entire toluene-degrading pathway. The amount of E. coli mRNA was estimated to be only 10% of that of P. putida mRNA. Consensus sequences of the -10 region (Pribnow box) and the -35 region (RNA polymerase recognition site) in E. coli genes were not found in the region preceding the transcription initiation site, whereas a sequence complementary to the 3' end of the 16S rRNA of Pseudomonas aeruginosa and E. coli existed in front of the predicted start codon of the xylA gene. These results explain the inefficient expression of TOL genes in E. coli.
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PMID:Nucleotide sequence surrounding transcription initiation site of xylABC operon on TOL plasmid of Pseudomonas putida. 632 12

Replication of exogenous RSF1010 DNA can be carried out by soluble enzyme systems from Escherichia coli and Pseudomonas aeruginosa. It requires the function of RSF1010-encoded replication protein(s), which is not expressed in extracts from plasmid-free bacteria. In contrast to previously described in vitro systems for plasmid replication, initiation of RSF1010 DNA synthesis is independent of transcription catalyzed by host RNA polymerase. This is indicated by the insensitivity of RSF1010 replication to rifampicin as well as to RNA polymerase antibodies. It is proposed that a host RNA polymerase transcription-independent initiation mechanism might be a general property of broad host range plasmids.
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PMID:Replication of the broad host range plasmid RSF1010 in cell-free extracts of Escherichia coli and Pseudomonas aeruginosa. 681 25

Plasmids containing the VA RNA genes of adenovirus are faithfully transcribed by a crude cytoplasmic extract containing DNA-dependent RNA polymerase III [Wu, G.-J. (1978) Proc. Natl. Acad. Sci. USA 75, 2175-2179]. By subjecting these DNA templates to in vitro site-directed mutagenesis with a novel enzyme of Pseudomonas and recloning in pBR322, we have constructed an ordered series of deletions which affect the in vitro transcription of the major RNA polymerase III viral product, VAI RNA. Three regions that are required for specific synthesis of VAI RNA can be defined. One, inside the gene at nucleotides +10 to +76, affects the transcription in an all-or-none fashion. Transcription is initiated on plasmid sequences that replace up to 10 nucleotides downstream from the 5' end of the gene. Variants with deletions past nucleotide +15 do not support the transcription of VAI RNA. Removal of 3'-end sequences downstream from +76 allows correct initiation. A second region, upstream from the initiation site, affects the exact alignment of the first nucleotide of the transcript [Thimmapaya, B., Jones, N. & Shenk, T. (1979) Cell 18, 947-959]. A third region, downstream from +76, encodes signals for termination of transcription, and new signals were brought in with other viral DNA sequences. Transcription competition experiments indicate that the primary site for binding of a transcriptional regulation factor is located between nucleotides +55 and +70 and suggest that the control region is bifunctional. An internal control region for VAI RNA, approximately 60 bases long and 11 bases downstream from the 5' end of the gene, can be defined.
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PMID:Control region for adenovirus VA RNA transcription. 694 46

The genetic organization of the Pseudomonas putida plasmid pWWO-161, which encodes enzymes for the degradation of toluene and related aromatic hydrocarbons, has been investigated by transposition mutagenesis and gene cloning. Catabolic genes were localized to two clusters, one for upper pathway (hydrocarbon leads to carboxylic acid) enzymes and the other for lower pathway (carboxylic acid leads to tricarboxylic acid cycle) enzymes, that are separated by a 14-kilobase DNA segment. The physical organization of the catabolic genes thus reflects their functional organization into two regulatory blocks. The pWWO-161 DNA fragments Sst I fragment C and fragment D were cloned in a broad host range vector to produce plasmid pKT530. This hybrid encodes toluate oxygenase and all meta cleavage pathway enzymes, and it enables P. putida mt-2 and Escherichia coli K-12 cells to grow on m-toluate as sole carbon source. The pKT530 plasmid also carries xylS (a gene whose product has been postulated to regulate expression of the lower pathway genes) and the control sequences of the pathway that interact with this product, because catechol 2,3-oxygenase synthesis is specifically induced by m-toluate in both P. putida and E. coli. Evidence is presented that suggests the promoter operator of the meta pathway gene functions less effectively with the RNA polymerase or xylS product of E. coli than with the enzyme or product of P. putida.
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PMID:Molecular and functional analysis of the TOL plasmid pWWO from Pseudomonas putida and cloning of genes for the entire regulated aromatic ring meta cleavage pathway. 695 Mar 88

The RNA polymerase in the nucleocapsid of Pseudomonas phaseolicola bacteriophage phi 6 transcribed large, medium, and small single-stranded RNA from the viral double-stranded RNA genome by a semiconservative (displacement) mechanism. Approximately 23%, 63%, and 65% of the nucleocapsid particles in the assay mixture synthesized at least one round of large, medium, and small single-stranded RNA molecules, respectively. Some of these particles reinitiated synthesis such that an average of 1.5 large, 33 medium, and 24 small single-stranded RNAs were synthesized from each double-stranded RNA.
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PMID:Semiconservative synthesis of single-stranded RNA by bacteriophage phi 6 RNA polymerase. 741 90

Treatment of Pseudomonas phaseolicola double-stranded RNA bacteriophage phi 6 with sodium deoxycholate converted the virions to nucleocapsids, which had in vitro RNA polymerase activity. The incorporation of [3H]UMP continued for at least 7 h. The initial incorporation was detected as intermediate RNA. Radioactivity was chased first into three segments of double-stranded RNA, and then into small, medium, and large species of single-stranded RNA successively via the intermediate RNA. Several copies of single-stranded RNA at least were synthesized from a template. The RNA synthesis clearly took place by a semi-conservative mechanism with respect to templates. That is, 5-bromo UTP was incorporated into one strand of double-stranded RNA to make a hybrid RNA of brominated and unbrominated strands. Furthermore, one strand of the 3H-labeled parental double-stranded RNA was shown to be released as single-stranded RNA.
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PMID:Semi-conservative transcription of double-stranded RNA catalyzed by bacteriophage phi 6 RNA polymerase. 746 97


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