Abstract
Highly purified Escherichia coli RNA polymerase contains a small subunit termed omega. This subunit consists of 91 amino acids with a molecular weight of 10,105. We previously reported the cloning and sequencing of the gene encoding omega, which we call rpoZ (D. R. Gentry and R. R. Burgess, Gene 48:33-40, 1986). We constructed an rpoZ insertion mutation by placing a kanamycin resistance cassette into the coding region of the rpoZ gene. Purified RNA polymerase from strains carrying this mutation lacked detectable omega. We found that the insertion mutation conferred a slow-growth phenotype when introduced into most strains. We mapped the position of rpoZ on the E. coli chromosome by genetic techniques and by examining the restriction map of the whole chromosome and found that rpoZ maps around 82 min, very close to spoT. We determined that the slow-growth phenotype of the insertion mutant is suppressed in relA mutants and that the rpoZ insertion results in a classical SpoT- phenotype. This finding strongly suggests that rpoZ is upstream of spoT in the same operon and that the slow-growth phenotype elicited by the insertion mutation is due to polarity on spoT.
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Selected References
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- An G., Justesen J., Watson R. J., Friesen J. D. Cloning the spoT gene of Escherichia coli: identification of the spoT gene product. J Bacteriol. 1979 Mar;137(3):1100–1110. doi: 10.1128/jb.137.3.1100-1110.1979. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Bochner B. R., Ames B. N. Complete analysis of cellular nucleotides by two-dimensional thin layer chromatography. J Biol Chem. 1982 Aug 25;257(16):9759–9769. [PubMed] [Google Scholar]
- Cashel M., Gallant J. Two compounds implicated in the function of the RC gene of Escherichia coli. Nature. 1969 Mar 1;221(5183):838–841. doi: 10.1038/221838a0. [DOI] [PubMed] [Google Scholar]
- Cashel M., Lazzarini R. A., Kalbacher B. An improved method for thin-layer chromatography of nucleotide mixtures containing 32P-labelled orthophosphate. J Chromatogr. 1969 Mar 11;40(1):103–109. doi: 10.1016/s0021-9673(01)96624-5. [DOI] [PubMed] [Google Scholar]
- Dykstra C. C., Prasher D., Kushner S. R. Physical and biochemical analysis of the cloned recB and recC genes of Escherichia coli K-12. J Bacteriol. 1984 Jan;157(1):21–27. doi: 10.1128/jb.157.1.21-27.1984. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Fiil N. P., Willumsen B. M., Friesen J. D., von Meyenburg K. Interaction of alleles of the relA, relC and spoT genes in Escherichia coli: analysis of the interconversion of GTP, ppGpp and pppGpp. Mol Gen Genet. 1977 Jan 7;150(1):87–101. doi: 10.1007/BF02425329. [DOI] [PubMed] [Google Scholar]
- Fukuda R., Yano R., Fukui T., Hase T., Ishihama A., Matsubara H. Cloning of the Escherichia coli gene for the stringent starvation protein. Mol Gen Genet. 1985;201(2):151–157. doi: 10.1007/BF00425652. [DOI] [PubMed] [Google Scholar]
- Gentry D. R., Burgess R. R. The cloning and sequence of the gene encoding the omega subunit of Escherichia coli RNA polymerase. Gene. 1986;48(1):33–40. doi: 10.1016/0378-1119(86)90349-5. [DOI] [PubMed] [Google Scholar]
- Kohara Y., Akiyama K., Isono K. The physical map of the whole E. coli chromosome: application of a new strategy for rapid analysis and sorting of a large genomic library. Cell. 1987 Jul 31;50(3):495–508. doi: 10.1016/0092-8674(87)90503-4. [DOI] [PubMed] [Google Scholar]
- Lazzarini R. A., Cashel M., Gallant J. On the regulation of guanosine tetraphosphate levels in stringent and relaxed strains of Escherichia coli. J Biol Chem. 1971 Jul 25;246(14):4381–4385. [PubMed] [Google Scholar]
- Lee J. S., An G., Friesen J. D., Isono K. Cloning and the nucleotide sequence of the genes for Escherichia coli ribosomal proteins L28 (rpmB) and L33 (rpmG). Mol Gen Genet. 1981;184(2):218–223. doi: 10.1007/BF00272908. [DOI] [PubMed] [Google Scholar]
- Neidhardt F. C., Bloch P. L., Smith D. F. Culture medium for enterobacteria. J Bacteriol. 1974 Sep;119(3):736–747. doi: 10.1128/jb.119.3.736-747.1974. [DOI] [PMC free article] [PubMed] [Google Scholar]
- STENT G. S., BRENNER S. A genetic locus for the regulation of ribonucleic acid synthesis. Proc Natl Acad Sci U S A. 1961 Dec 15;47:2005–2014. doi: 10.1073/pnas.47.12.2005. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Winans S. C., Elledge S. J., Krueger J. H., Walker G. C. Site-directed insertion and deletion mutagenesis with cloned fragments in Escherichia coli. J Bacteriol. 1985 Mar;161(3):1219–1221. doi: 10.1128/jb.161.3.1219-1221.1985. [DOI] [PMC free article] [PubMed] [Google Scholar]