Abstract
The nagC gene, encoding the NagC repressor/activator of the nag regulon, is part of the nagBACD operon. When the promoter-proximal nagB and nagA genes are induced 20- to 40-fold, the nagC gene is induced only two- to threefold. In addition to being transcribed as part of the polycistronic nagBACD mRNA, nagC is also expressed from two promoters located within the upstream nagA gene. These promoters are comparable in strength to the induced nagB promoter, resulting in a high basal level of the nagC mRNA. This means that when the nagBA genes are induced, there is a much smaller effect on the amount of nagC mRNA. The nagC gene is subject to low-level translation so that the amount of NagC protein is kept low despite the relatively high transcription levels.
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- Adhya S., Gottesman M. Promoter occlusion: transcription through a promoter may inhibit its activity. Cell. 1982 Jul;29(3):939–944. doi: 10.1016/0092-8674(82)90456-1. [DOI] [PubMed] [Google Scholar]
- Aiba H. Autoregulation of the Escherichia coli crp gene: CRP is a transcriptional repressor for its own gene. Cell. 1983 Jan;32(1):141–149. doi: 10.1016/0092-8674(83)90504-4. [DOI] [PubMed] [Google Scholar]
- Casadaban M. J., Martinez-Arias A., Shapira S. K., Chou J. Beta-galactosidase gene fusions for analyzing gene expression in escherichia coli and yeast. Methods Enzymol. 1983;100:293–308. doi: 10.1016/0076-6879(83)00063-4. [DOI] [PubMed] [Google Scholar]
- Chapon C. Expression of malT, the regulator gene of the maltose region in Escherichia coli, is limited both at transcription and translation. EMBO J. 1982;1(3):369–374. doi: 10.1002/j.1460-2075.1982.tb01176.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Curtis S. J., Epstein W. Phosphorylation of D-glucose in Escherichia coli mutants defective in glucosephosphotransferase, mannosephosphotransferase, and glucokinase. J Bacteriol. 1975 Jun;122(3):1189–1199. doi: 10.1128/jb.122.3.1189-1199.1975. [DOI] [PMC free article] [PubMed] [Google Scholar]
- De Lorenzo V., Herrero M., Giovannini F., Neilands J. B. Fur (ferric uptake regulation) protein and CAP (catabolite-activator protein) modulate transcription of fur gene in Escherichia coli. Eur J Biochem. 1988 May 2;173(3):537–546. doi: 10.1111/j.1432-1033.1988.tb14032.x. [DOI] [PubMed] [Google Scholar]
- Debarbouille M., Schwartz M. The use of gene fusions to study the expression of malT the positive regulator gene of the maltose regulon. J Mol Biol. 1979 Aug 15;132(3):521–534. doi: 10.1016/0022-2836(79)90273-0. [DOI] [PubMed] [Google Scholar]
- Figge R. M., Ramseier T. M., Saier M. H., Jr The mannitol repressor (MtlR) of Escherichia coli. J Bacteriol. 1994 Feb;176(3):840–847. doi: 10.1128/jb.176.3.840-847.1994. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Gafny R., Cohen S., Nachaliel N., Glaser G. Isolated P2 rRNA promoters of Escherichia coli are strong promoters that are subject to stringent control. J Mol Biol. 1994 Oct 21;243(2):152–156. doi: 10.1006/jmbi.1994.1641. [DOI] [PubMed] [Google Scholar]
- Gerlach P., Valentin-Hansen P., Bremer E. Transcriptional regulation of the cytR repressor gene of Escherichia coli: autoregulation and positive control by the cAMP/CAP complex. Mol Microbiol. 1990 Mar;4(3):479–488. doi: 10.1111/j.1365-2958.1990.tb00614.x. [DOI] [PubMed] [Google Scholar]
- Hanamura A., Aiba H. A new aspect of transcriptional control of the Escherichia coli crp gene: positive autoregulation. Mol Microbiol. 1992 Sep;6(17):2489–2497. doi: 10.1111/j.1365-2958.1992.tb01425.x. [DOI] [PubMed] [Google Scholar]
- Hanamura A., Aiba H. Molecular mechanism of negative autoregulation of Escherichia coli crp gene. Nucleic Acids Res. 1991 Aug 25;19(16):4413–4419. doi: 10.1093/nar/19.16.4413. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Harley C. B., Reynolds R. P. Analysis of E. coli promoter sequences. Nucleic Acids Res. 1987 Mar 11;15(5):2343–2361. doi: 10.1093/nar/15.5.2343. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Hawley D. K., McClure W. R. Compilation and analysis of Escherichia coli promoter DNA sequences. Nucleic Acids Res. 1983 Apr 25;11(8):2237–2255. doi: 10.1093/nar/11.8.2237. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Jones-Mortimer M. C., Kornberg H. L. Amino-sugar transport systems of Escherichia coli K12. J Gen Microbiol. 1980 Apr;117(2):369–376. doi: 10.1099/00221287-117-2-369. [DOI] [PubMed] [Google Scholar]
- Kelley R. L., Yanofsky C. Trp aporepressor production is controlled by autogenous regulation and inefficient translation. Proc Natl Acad Sci U S A. 1982 May;79(10):3120–3124. doi: 10.1073/pnas.79.10.3120. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Lim D. B., Oppenheim J. D., Eckhardt T., Maas W. K. Nucleotide sequence of the argR gene of Escherichia coli K-12 and isolation of its product, the arginine repressor. Proc Natl Acad Sci U S A. 1987 Oct;84(19):6697–6701. doi: 10.1073/pnas.84.19.6697. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Maas W. K. The arginine repressor of Escherichia coli. Microbiol Rev. 1994 Dec;58(4):631–640. doi: 10.1128/mr.58.4.631-640.1994. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Meng L. M., Kilstrup M., Nygaard P. Autoregulation of PurR repressor synthesis and involvement of purR in the regulation of purB, purC, purL, purMN and guaBA expression in Escherichia coli. Eur J Biochem. 1990 Jan 26;187(2):373–379. doi: 10.1111/j.1432-1033.1990.tb15314.x. [DOI] [PubMed] [Google Scholar]
- Mengin-Lecreulx D., van Heijenoort J. Copurification of glucosamine-1-phosphate acetyltransferase and N-acetylglucosamine-1-phosphate uridyltransferase activities of Escherichia coli: characterization of the glmU gene product as a bifunctional enzyme catalyzing two subsequent steps in the pathway for UDP-N-acetylglucosamine synthesis. J Bacteriol. 1994 Sep;176(18):5788–5795. doi: 10.1128/jb.176.18.5788-5795.1994. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Mengin-Lecreulx D., van Heijenoort J. Identification of the glmU gene encoding N-acetylglucosamine-1-phosphate uridyltransferase in Escherichia coli. J Bacteriol. 1993 Oct;175(19):6150–6157. doi: 10.1128/jb.175.19.6150-6157.1993. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Minton N. P. Improved plasmid vectors for the isolation of translational lac gene fusions. Gene. 1984 Nov;31(1-3):269–273. doi: 10.1016/0378-1119(84)90220-8. [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]
- Okamoto K., Freundlich M. Mechanism for the autogenous control of the crp operon: transcriptional inhibition by a divergent RNA transcript. Proc Natl Acad Sci U S A. 1986 Jul;83(14):5000–5004. doi: 10.1073/pnas.83.14.5000. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Peri K. G., Goldie H., Waygood E. B. Cloning and characterization of the N-acetylglucosamine operon of Escherichia coli. Biochem Cell Biol. 1990 Jan;68(1):123–137. doi: 10.1139/o90-017. [DOI] [PubMed] [Google Scholar]
- Plumbridge J. A. A dominant mutation in the gene for the Nag repressor of Escherichia coli that renders the nag regulon uninducible. J Gen Microbiol. 1992 May;138(5):1011–1017. doi: 10.1099/00221287-138-5-1011. [DOI] [PubMed] [Google Scholar]
- Plumbridge J. A. Induction of the nag regulon of Escherichia coli by N-acetylglucosamine and glucosamine: role of the cyclic AMP-catabolite activator protein complex in expression of the regulon. J Bacteriol. 1990 May;172(5):2728–2735. doi: 10.1128/jb.172.5.2728-2735.1990. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Plumbridge J. A. Repression and induction of the nag regulon of Escherichia coli K-12: the roles of nagC and nagA in maintenance of the uninduced state. Mol Microbiol. 1991 Aug;5(8):2053–2062. doi: 10.1111/j.1365-2958.1991.tb00828.x. [DOI] [PubMed] [Google Scholar]
- Plumbridge J. A. Sequence of the nagBACD operon in Escherichia coli K12 and pattern of transcription within the nag regulon. Mol Microbiol. 1989 Apr;3(4):505–515. doi: 10.1111/j.1365-2958.1989.tb00197.x. [DOI] [PubMed] [Google Scholar]
- Plumbridge J. Co-ordinated regulation of amino sugar biosynthesis and degradation: the NagC repressor acts as both an activator and a repressor for the transcription of the glmUS operon and requires two separated NagC binding sites. EMBO J. 1995 Aug 15;14(16):3958–3965. doi: 10.1002/j.1460-2075.1995.tb00067.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Plumbridge J., Kolb A. CAP and Nag repressor binding to the regulatory regions of the nagE-B and manX genes of Escherichia coli. J Mol Biol. 1991 Feb 20;217(4):661–679. doi: 10.1016/0022-2836(91)90524-a. [DOI] [PubMed] [Google Scholar]
- Plumbridge J., Kolb A. DNA loop formation between Nag repressor molecules bound to its two operator sites is necessary for repression of the nag regulon of Escherichia coli in vivo. Mol Microbiol. 1993 Dec;10(5):973–981. doi: 10.1111/j.1365-2958.1993.tb00969.x. [DOI] [PubMed] [Google Scholar]
- Plumbridge J., Kolb A. Nag repressor-operator interactions: protein-DNA contacts cover more than two turns of the DNA helix. J Mol Biol. 1995 Jun 23;249(5):890–902. doi: 10.1006/jmbi.1995.0346. [DOI] [PubMed] [Google Scholar]
- Rogers M. J., Ohgi T., Plumbridge J., Söll D. Nucleotide sequences of the Escherichia coli nagE and nagB genes: the structural genes for the N-acetylglucosamine transport protein of the bacterial phosphoenolpyruvate: sugar phosphotransferase system and for glucosamine-6-phosphate deaminase. Gene. 1988;62(2):197–207. doi: 10.1016/0378-1119(88)90558-6. [DOI] [PubMed] [Google Scholar]
- Schauder B., Blöcker H., Frank R., McCarthy J. E. Inducible expression vectors incorporating the Escherichia coli atpE translational initiation region. Gene. 1987;52(2-3):279–283. doi: 10.1016/0378-1119(87)90054-0. [DOI] [PubMed] [Google Scholar]
- Simons R. W., Houman F., Kleckner N. Improved single and multicopy lac-based cloning vectors for protein and operon fusions. Gene. 1987;53(1):85–96. doi: 10.1016/0378-1119(87)90095-3. [DOI] [PubMed] [Google Scholar]
- Valentin-Hansen P., Svenningsen B. A., Munch-Petersen A., Hammer-Jespersen K. Regulation of the deo operon in Escherichia coli: the double negative control of the deo operon by the cytR and deoR repressors in a DNA directed in vitro system. Mol Gen Genet. 1978 Feb 16;159(2):191–202. doi: 10.1007/BF00270893. [DOI] [PubMed] [Google Scholar]
- Vogler A. P., Lengeler J. W. Analysis of the nag regulon from Escherichia coli K12 and Klebsiella pneumoniae and of its regulation. Mol Gen Genet. 1989 Oct;219(1-2):97–105. doi: 10.1007/BF00261163. [DOI] [PubMed] [Google Scholar]
- Weickert M. J., Adhya S. Control of transcription of gal repressor and isorepressor genes in Escherichia coli. J Bacteriol. 1993 Jan;175(1):251–258. doi: 10.1128/jb.175.1.251-258.1993. [DOI] [PMC free article] [PubMed] [Google Scholar]
- White R. J. Control of amino sugar metabolism in Escherichia coli and isolation of mutants unable to degrade amino sugars. Biochem J. 1968 Feb;106(4):847–858. doi: 10.1042/bj1060847. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Yamada M., Saier M. H., Jr Positive and negative regulators for glucitol (gut) operon expression in Escherichia coli. J Mol Biol. 1988 Oct 5;203(3):569–583. doi: 10.1016/0022-2836(88)90193-3. [DOI] [PubMed] [Google Scholar]
- Yarchuk O., Jacques N., Guillerez J., Dreyfus M. Interdependence of translation, transcription and mRNA degradation in the lacZ gene. J Mol Biol. 1992 Aug 5;226(3):581–596. doi: 10.1016/0022-2836(92)90617-s. [DOI] [PubMed] [Google Scholar]