Abstract
The transcriptional control region of THE E. coli DNA topoisomerase I (topA) gene has been fused to the galactokinase (galK) gene coding region in a recombinant plasmid. In vivo synthesis of the galactokinase produced from such a plasmid has been measured and found to be reduced when mutations in the genes coding for DNA gyrase subunits are introduced into the cell or when gyrase inhibitors are present. In vitro transcription-translation of the galactokinase gene product confirms that a supercoiled DNA template is required for efficient transcription from the topA gene promoter. These results indicate that the amount of DNA topoisomerase I activity in E. coli is regulated by the extent of DNA supercoiling and can contribute to the overall modulation of DNA superhelicity and the expression of other genes.
Full text
PDF












Images in this article
Selected References
These references are in PubMed. This may not be the complete list of references from this article.
- Adams C. W., Hatfield G. W. Effects of promoter strengths and growth conditions on copy number of transcription-fusion vectors. J Biol Chem. 1984 Jun 25;259(12):7399–7403. [PubMed] [Google Scholar]
- Dean F., Krasnow M. A., Otter R., Matzuk M. M., Spengler S. J., Cozzarelli N. R. Escherichia coli type-1 topoisomerases: identification, mechanism, and role in recombination. Cold Spring Harb Symp Quant Biol. 1983;47(Pt 2):769–777. doi: 10.1101/sqb.1983.047.01.088. [DOI] [PubMed] [Google Scholar]
- DiNardo S., Voelkel K. A., Sternglanz R., Reynolds A. E., Wright A. Escherichia coli DNA topoisomerase I mutants have compensatory mutations in DNA gyrase genes. Cell. 1982 Nov;31(1):43–51. doi: 10.1016/0092-8674(82)90403-2. [DOI] [PubMed] [Google Scholar]
- Gamper H. B., Hearst J. E. A topological model for transcription based on unwinding angle analysis of E. coli RNA polymerase binary, initiation and ternary complexes. Cell. 1982 May;29(1):81–90. doi: 10.1016/0092-8674(82)90092-7. [DOI] [PubMed] [Google Scholar]
- Gellert M. DNA topoisomerases. Annu Rev Biochem. 1981;50:879–910. doi: 10.1146/annurev.bi.50.070181.004311. [DOI] [PubMed] [Google Scholar]
- Holmes D. S., Quigley M. A rapid boiling method for the preparation of bacterial plasmids. Anal Biochem. 1981 Jun;114(1):193–197. doi: 10.1016/0003-2697(81)90473-5. [DOI] [PubMed] [Google Scholar]
- Kirkegaard K., Buc H., Spassky A., Wang J. C. Mapping of single-stranded regions in duplex DNA at the sequence level: single-strand-specific cytosine methylation in RNA polymerase-promoter complexes. Proc Natl Acad Sci U S A. 1983 May;80(9):2544–2548. doi: 10.1073/pnas.80.9.2544. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Laemmli U. K. Cleavage of structural proteins during the assembly of the head of bacteriophage T4. Nature. 1970 Aug 15;227(5259):680–685. doi: 10.1038/227680a0. [DOI] [PubMed] [Google Scholar]
- Melnikova A. F., Beabealashvilli R., Mirzabekov A. D. A study of unwinding of DNA and shielding of the DNA grooves by RNA polymerase by using methylation with dimethylsulphate. Eur J Biochem. 1978 Mar;84(1):301–309. doi: 10.1111/j.1432-1033.1978.tb12169.x. [DOI] [PubMed] [Google Scholar]
- Menzel R., Gellert M. Regulation of the genes for E. coli DNA gyrase: homeostatic control of DNA supercoiling. Cell. 1983 Aug;34(1):105–113. doi: 10.1016/0092-8674(83)90140-x. [DOI] [PubMed] [Google Scholar]
- Pruss G. J., Manes S. H., Drlica K. Escherichia coli DNA topoisomerase I mutants: increased supercoiling is corrected by mutations near gyrase genes. Cell. 1982 Nov;31(1):35–42. doi: 10.1016/0092-8674(82)90402-0. [DOI] [PubMed] [Google Scholar]
- Rosenberg M., Chepelinsky A. B., McKenney K. Studying promoters and terminators by gene fusion. Science. 1983 Nov 18;222(4625):734–739. doi: 10.1126/science.6356355. [DOI] [PubMed] [Google Scholar]
- Saucier J. M., Wang J. C. Angular alteration of the DNA helix by E. coli RNA polymerase. Nat New Biol. 1972 Oct 11;239(93):167–170. doi: 10.1038/newbio239167a0. [DOI] [PubMed] [Google Scholar]
- Shure M., Pulleyblank D. E., Vinograd J. The problems of eukaryotic and prokaryotic DNA packaging and in vivo conformation posed by superhelix density heterogeneity. Nucleic Acids Res. 1977;4(5):1183–1205. doi: 10.1093/nar/4.5.1183. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Siebenlist U. RNA polymerase unwinds an 11-base pair segment of a phage T7 promoter. Nature. 1979 Jun 14;279(5714):651–652. doi: 10.1038/279651a0. [DOI] [PubMed] [Google Scholar]
- Siebenlist U., Simpson R. B., Gilbert W. E. coli RNA polymerase interacts homologously with two different promoters. Cell. 1980 Jun;20(2):269–281. doi: 10.1016/0092-8674(80)90613-3. [DOI] [PubMed] [Google Scholar]
- Sternglanz R., DiNardo S., Voelkel K. A., Nishimura Y., Hirota Y., Becherer K., Zumstein L., Wang J. C. Mutations in the gene coding for Escherichia coli DNA topoisomerase I affect transcription and transposition. Proc Natl Acad Sci U S A. 1981 May;78(5):2747–2751. doi: 10.1073/pnas.78.5.2747. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Strothkamp R. E., Oakley J. L., Coleman J. E. Promoter melting by T7 ribonucleic acid polymerase as detected by single-stranded endonuclease digestion. Biochemistry. 1980 Mar 18;19(6):1074–1080. doi: 10.1021/bi00547a005. [DOI] [PubMed] [Google Scholar]
- Twigg A. J., Sherratt D. Trans-complementable copy-number mutants of plasmid ColE1. Nature. 1980 Jan 10;283(5743):216–218. doi: 10.1038/283216a0. [DOI] [PubMed] [Google Scholar]
- Waley S. G. A spectrophotometric assay of beta-lactamase action on penicillins. Biochem J. 1974 Jun;139(3):789–790. doi: 10.1042/bj1390789. [DOI] [PMC free article] [PubMed] [Google Scholar]