Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:2.7.7.7 (DNA polymerase)
 17,007 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The delta subunit of DNA polymerase III holoenzyme has been purified extensively with an assay for phi X174 DNA synthesis using core (pol III) and beta and gamma subunits. Either the purified delta subunit or the purified DNA polymerase III holoenzyme can complement a defective enzyme fraction from the conditional replication mutant SG133 described by Sevastopoulos et al. [Sevastopoulas, C.G., Wehr, C.T. & Glaser, D. A. (1977) Proc. Natl. Acad. Sci. USA 74, 3485-3489]. It has been established by Henson et al. [Henson, J.M., Chu, H., Irwin, C.A. & Walker, J.R. (1979) Genetics 92, 1,41-1059] that SG133 has two temperature-sensitive mutations, called dnaX and dnaY. The crude enzyme source from dnaX can be complemented by the delta subunit and by DNA polymerase III holoenzyme. By contrast, the core DNA polymerase III and the beta and gamma subunits are unable to complement this defective enzyme fraction. Thus, the delta subunit of DNA polymerase III holoenzyme appears to be the dnaX gene product of Escherichia coli.
Proc Natl Acad Sci U S A 1979 Dec
PMID:The delta subunit of Escherichia coli DNA polymerase III holoenzyme is the dnaX gene product. 16 May 63

A synthetic oligodeoxyribonucleotide mismatched at a single nucleotide to a specific complementary site on wild-type circular phi X174 DNA can be used to produce a defined point mutation after in vitro incorporation into closed circular duplex DNA by elongation with DNA polymerase and ligation followed by transfection of Escherichia coli (Hutchison et al., 1978; Gillam et al., 1979). The present study is an investigation of the optimum conditions required for the oligodeoxyribonucleotide-primed reaction for production of transition and transversion mutations in phi X174 DNA, using the large (Klenow) fragment of E. coli DNA polymerase I. Under optimum conditions up to 39% of the progeny of transfection are the desired mutant and significant mutation is observed using a heptadeoxyribonucleotide.
Gene 1979 Dec
PMID:Site-specific mutagenesis using synthetic oligodeoxyribonucleotide primers: I. Optimum conditions and minimum ologodeoxyribonucleotide length. 16 Dec 45

A method for the in vitro selection of mutant DNA has been devised as an adjunct to the recently developed method for the use of short enzymatically-synthesized oligodeoxyribonucleotides of defined sequence as site-specific mutagens for circular DNA. The selection method uses the mutating oligodeoxyribonucleotide as a primer for Escherichia coli DNA polymerase I (large fragment) under conditions where there is preferential interaction with mutant DNA template. After ligation using T4 DNA ligase, endonuclease S1 is used to degrade single-stranded non-mutant DNA leaving the desired mutant as closed circular duplex DNA. This paper describes the development of the method using mutants in phi X174 DNA as the model system. Studiies on the changes A leads to G and G leads to A at position 587 of phi X174 viral DNA (am3 to wild-type and its reversal) show that one or two cycles of selection can lead to a population of phage consisting of close to 100% mutants.
Gene 1979 Dec
PMID:Site-specific mutagenesis using synthetic oligodeoxyribonucleotide primers: II. In vitro selection of mutant DNA. 16 Dec 46

Phosphonoacetic acid specifically inhibited human cytomegalovirus DNA synthesis in virus-infected human fibroblasts as detected by virus-specific nucleic acid hybridization. Inhibition was reversible; viral DNA synthesis resumed upon the removal of the drug. The compound partially inhibited DNA synthesis of host cells in the log phase of growth but had little effect on confluent cells. Studies of partially purified enzymes indicated that phosphonoacetic acid specifically inhibited virus-induced DNA polymerase and had only a slight effect on normal host cell enzymes. The drug was shown to interact directly with virus-induced enzyme but not with the template-primers.
J Virol 1975 Dec
PMID:Human cytomegalovirus. IV. Specific inhibition of virus-induced DNA polymerase activity and viral DNA replication by phosphonoacetic acid. 17 57

Purified nuclei, isolated from appropriately infected HeLa cells, are shown to synthesize large amounts of either herpes simplex virus (HSV) or vaccinia virus DNA in vitro. The rate of synthesis of DNA by nuclei from infected cells is up to 30 times higher than the synthesis of host DNA in vitro by nuclei isolated from uninfected HeLa cells. Thus HSV nuclei obtained from HSV-infected cells make DNA in vitro at a rate comparable to that seen in the intact, infected cell. Molecular hybridization studies showed that 80% of the DNA sequences synthesized in vitro by nuclei from herpesvirus-infected cells are herpesvirus specific. Vaccinia virus nuclei from vaccinia virus-infected cells, also produce comparable percentages of vaccinia virus-specific DNA sequences. Adenovirus nuclei from adenovirus 2-infected HeLa cells, which also synthesize viral DNA in vitro, have been included in this study. Synthesis of DNA by HSV or vaccinia virus nuclei is markedly inhibited by the corresponding viral-specific antisera. These antisera inhibit in a similar fashion the purified herpesvirus-induced or vaccinia virus-induced DNA polymerase isolated from infected cells. Phosphonoacetic acid, reported to be a specific inhibitor of herpesvirus formation and the herpesvirus-induced DNA polymerase, is equally effective as an inhibitor of HSV DNA synthesis in isolated nuclei in vitro. However, we also find phosphonoacetic acid to be an effective inhibitor of vaccinia virus nuclear DNA synthesis and the purified vaccinia virus-induced DNA polymerase. In addition, this compound shows significant inhibition of DNA synthesis in isolated nuclei obtained from adenovirus-infected or uninfected cells and is a potent inhibitor of HeLa cell DNA polymerase alpha.
J Virol 1975 Dec
PMID:Synthesis of herpes simplex virus, vaccinia virus, and adenovirus DNA in isolated HeLa cell nuclei. I. Effect of viral-specific antisera and phosphonoacetic acid. 17 58

Varying the concentration of Triton X-100, a nonionic detergent used to promote the DNA polymerase activity of Rous sarcoma virus in an endogenous reaction, showed a very sharp peak at about 0.02% (vol/vol) for optimal DNA synthesis. The yield of DNA at this concentration of Triton exceeded yields obtained at concentrations above the optimum by a factor of 2-5 for the 90-min reaction. At optimal Triton concentration, about 1-7% of the DNA made in the absence of actinomycin and about 4-10% of the DNA made in the presence of actinomycin was 2.5 X 10(6) daltons or greater, as estimated by formamide polyacrylamide gel electrophoresis and by alkaline sucrose gradient sedimentation. No large DNA was obtained at higher than optimal Triton concentrations. The large DNA molecules were rendered totally resistant to single-strand specific nuclease S1 after hybridization to an excess of viral RNA. It was concluded that at optimal detergent concentration, the viral DNA polymerase can synthesize full-size DNA transcripts of viral RNA.
Proc Natl Acad Sci U S A 1975 Dec
PMID:In vitro synthesis of full-length DNA transcripts of Rous sarcoma virus RNA by viral DNA polymerase. 17 81

Cytomegalovirus-induced DNA polymerase can be distinguished from infected-cell enzymes by activity in 100 mM (NH4)2SO4. Virus polymerase is stimulated to 145% of control, whereas mock-infected cell polymerase is inhibited to 12% of control without added salt. Mycoplasmas induce a DNA polymerase in cell extracts that is stimulated to 130 to 180% by 25 mM (NH4)2SO4. Mycoplasma DNA polymerase may be mistaken for a virus-induced polymerase when virus stocks are contaminated. Identification of virus, cellular, and mycoplasma DNA polymerases in total cell extracts is described using sedimentation rate and effect of inhibitors on DNA polymerase activities.
J Virol 1976 Dec
PMID:Distinguishing cytomegalovirus, mycoplasma, and cellular DNA polymerases. 18 34

A guanine derivative with an acyclic side chain, 2-hydroxyethoxymethyl, at position 9 has potent antiviral activity [dose for 50% inhibition (ED(50)) = 0.1 muM] against herpes simplex virus type 1. This acyclic nucleoside analog, termed acycloguanosine, is converted to a monophosphate by a virus-specified pyrimidine deoxynucleoside (thymidine) kinase and is subsequently converted to acycloguanosine di- and triphosphates. In the uninfected host cell (Vero) these phosphorylations of acycloguanosine occur to a very limited extent. Acycloguanosine triphosphate inhibits herpes simplex virus DNA polymerase (DNA nucleotidyltransferase) 10-30 times more effectively than cellular (HeLa S3) DNA polymerase. These factors contribute to the drug's selectivity; inhibition of growth of the host cell requires a 3000-fold greater concentration of drug than does the inhibition of viral multiplication. There is, moreover, the strong possibility of chain termination of the viral DNA by incorporation of acycloguanosine. The identity of the kinase that phosphorylates acycloguanosine was determined after separation of the cellular and virus-specified thymidine kinase activities by affinity chromatography, by reversal studies with thymidine, and by the lack of monophosphate formation in a temperature-sensitive, thymidine kinase-deficient mutant of the KOS strain of herpes simplex virus type 1 (tsA1).
Proc Natl Acad Sci U S A 1977 Dec
PMID:Selectivity of action of an antiherpetic agent, 9-(2-hydroxyethoxymethyl) guanine. 20 61

We have partially purified and characterized two separate DNA polymerase activities associated with Epstein-Barr virus (EB virus). One activity is present in EB virus producer cell lines but not in nonproducer or negative cell lines. It adheres more strongly to DEAE-cellulose than any host cell enzymes, eluting at 210 to 270 mM potassium phosphate buffer. Further elution from phosphocellulose and sedimentation in glycerol gradients yields an enzyme purified 900-fold with an S value of 8.3. The second DNA polymerase activity co-purifies with EB viral particles, elutes at low salt from DEAE-cellulose (40 to 60 mM potassium phosphate buffer) and phosphocellulose (100 mM), and has an S value of 9.5 on glycerol gradient sedimentation. These two enzymes are referred to for convenience as the EB virus-induced DNA polymerase and the EB virion-associated DNA polymerase. The EB virus-induced polymerase can be distinguished from host alpha, beta, and the virion-associated polymerase in 1) being resistant to salt inhibition, 2) having a more basic pH optima in Tris buffer (pH 9.5), and 3) having a 10-fold lower saturating concentration for the activated DNA template. The EB virion-associated polymerase is distinguished from host alpha, beta, and the EB virus-induced polymerase, because it cannot utilize synthetic deoxy- and ribohomopolymer primer-templates in place of the activated calf thymus DNA template in DNA polymerase assays. Neither of the EB virus-associated polymerases can copy the ribohomopolymers dT10poly(rA) or dG12-18(poly(rC) efficiently and therefore can be distinguished from host gamma polymerase and reverse transcriptase. The activity of the EB virus-induced and virion-associated polymerases are unaffected both by antibody to alpha polymerase, and by antiserum with high antibody titers to EB early antigen and viral capsid antigen.
J Biol Chem 1978 Dec 10
PMID:Two Epstein-Barr virus-associated DNA polymerase activities. 21 39

Three major species of viral DNA have been observed in cells infected by retroviruses: a linear, double-stranded copy of a subunit of viral RNA; closed circular DNA; and proviral DNA inserted covalently into the genome of the host cell. We have studied the structures of the unintegrated forms of avian sarcoma virus (ASA) DNA using agarose gel electrophoresis in conjunction with restriction endonucleases and molecular hybridization techniques. The linear duplex DNA is approximately the same length as a subunit of viral RNA (approximately 10 kb) and it bears natural repeats of approximately 300 nucleotides at its termini. The repeats are composed of sequences derived from both the 3' and 5' termini of viral RNA in a manner suggesting that the viral DNA polymerase is transferred twice between templates. Thus the first end begins with a sequence from the 5' terminus of viral RNA and is permuted by about 100 nucleotides with respect to the 3' terminus of viral RNA; the linear DNA terminates with a sequence of about 200 nucleotides derived from the 3' end of viral RNA. We represent this structure, synthesized from right to left, as 3'5'-----3'5'. Two closed circular species of approximately monomeric size have been identified. The less abundant species contain all the sequences identified in linear DNA, including two copies in tandem of the 300 nucleotide 3'5' repeat. The major species lacks about 300 base pairs (bp) mapped to the region of the repeated sequence; thus it presumably contains only a single copy of that sequence. The strategies used to determine these structures involved the assignment of over 20 cleavage sites for restriction endonucleases on the physical maps of ASV DNA. Several strains of ASV were compared with respect to these sites, and the sites have been located in relation to deletions frequently observed in the env and src genes of ASV.
Cell 1978 Dec
PMID:Mapping unintegrated avian sarcoma virus DNA: termini of linear DNA bear 300 nucleotides present once or twice in two species of circular DNA. 21 24


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