Negative transcriptional regulation of the operon in Free

Abstract

is one of the four operons in that encode exported proteins with a probable role in the virulence of this bacterium. Upstream of there is a putative regulatory gene () that harbours a double -family signature. To study the role of this putative regulatory gene in the transcriptional regulation of the operon, mc155 and H37Rv strains that harboured gene fusions between the promoter region and the gene, either containing or not containing the gene, were used. The presence of the gene in the strains greatly reduced β-galactosidase activity, suggesting that the -encoded protein is a transcriptional repressor of the operon. Expression of by recombinant was increased when it was grown in a macrophage-like cell line (J774), compared to the level of expression seen when the recombinant bacterium was grown under conditions. However, no lifting of repression was induced. The 3 promoter was defined by deletion and cloning of the intergenic region in a 200 bp DNA fragment harbouring the region upstream of the start codon. Gel-shift experiments determined that the Rv1963-binding site was located in this region. These results indicate that the operon is transcriptionally regulated and that under certain, unknown, conditions repression of gene expression could be lifted.

Loading

Article metrics loading...

/content/journal/micro/10.1099/00221287-148-10-2997
2002-10-01
2024-03-29
Loading full text...

Full text loading...

/deliver/fulltext/micro/148/10/1482997a.html?itemId=/content/journal/micro/10.1099/00221287-148-10-2997&mimeType=html&fmt=ahah

References

  1. Ahmad S, Akbar P. K, Wiker H. G, Harboe M., Mustafa A. S. 1999; Cloning, expression and immunological reactivity of two mammalian cell entry proteins encoded by the mce1 operon of Mycobacterium tuberculosis . Scand J Immunol 50:510–518
    [Google Scholar]
  2. Arruda S, Bonfim G, Knights R, Huima-Byron T., Riley L. W. 1993; Cloning of an M. tuberculosis DNA fragment associated with entry and survival inside cells. Science 261:1454–1457
    [Google Scholar]
  3. Bange F. C, Collins F. M., Jacobs W. R. Jr 1999; Survival of mice infected with Mycobacterium smegmatis containing large DNA fragments from Mycobacterium tuberculosis . Tuber Lung Dis 79:171–180
    [Google Scholar]
  4. Camacho L. R, Ensergueix D, Perez E, Gicquel B., Guilhot C. 1999; Identification of a virulence gene cluster of Mycobacterium tuberculosis by signature-tagged transposon mutagenesis. Mol Microbiol 34:257–267
    [Google Scholar]
  5. Cataldi A, Romano M. I., Bigi F. 1994; A western blot characterization of Mycobacterium bovis antigens recognized by cattle sera. Res Microbiol 145:689–698
    [Google Scholar]
  6. Chitale S, Ehrt S, Kawamura I, Fujimura T, Shimono N, Anand N, Lu S, Cohen-Gould L., Riley L. W. 2001; Recombinant Mycobacterium tuberculosis protein associated with mammalian cell entry. Cell Microbiol 3:247–254
    [Google Scholar]
  7. Cole S. T, Brosch R, Parkhill J. 39 other authors 1998; Deciphering the biology of Mycobacterium tuberculosis from the complete genome sequence. Nature 393:537–544
    [Google Scholar]
  8. Cole S. T, Eiglmeier K, Parkhill J. 41 other authors 2001; Massive gene decay in the leprosy bacillus. Nature 409:1007–1011
    [Google Scholar]
  9. Cox J. S, Chen B, McNeil M., Jacobs W. R. Jr 1999; Complex lipid determines tissue-specific replication of Mycobacterium tuberculosis in mice. Nature 402:79–83
    [Google Scholar]
  10. Fisanotti J. C, Romano M. I, Alito A, Bigi F., Cataldi A. 1997; An mpb-64 flanking sequence specific for Mycobacterium bovis . Res Microbiol 148:427–435
    [Google Scholar]
  11. Flesselles B, Anand N. N, Remani J, Loosmore S. M., Klein M. H. 1999; Disruption of the mycobacterial cell entry gene of Mycobacterium bovis BCG results in a mutant that exhibits a reduced invasiveness for epithelial cells. FEMS Microbiol Lett 15:237–242
    [Google Scholar]
  12. Gordon S. V, Brosch R, Billault A, Garnier T, Eiglmeier K., Cole S. T. 1999; Identification of variable regions in the genomes of tubercle bacilli using bacterial artificial chromosome arrays. Mol Microbiol 32:643–655
    [Google Scholar]
  13. Grkovic S, Brown M. H, Roberts N. J, Paulsen I. T., Skurray R. A. 1998; QacR is a repressor protein that regulates expression of the Staphylococcus aureus multidrug efflux pump QacA. J Biol Chem 273:18665–18673
    [Google Scholar]
  14. Harboe M, Christensen A, Haile Y, Ulvund G, Ahmad S, Mustafa A. S., Wiker H. G. 1999; Demonstration of expression of six proteins of the mammalian cell entry ( mce1 ) operon of Mycobacterium tuberculosis by anti-peptide antibodies, enzyme-linked immunosorbent assay and reverse transcription-polymerase chain reaction. Scand J Immunol 50:519–527
    [Google Scholar]
  15. Lucas C. E, Balthazar J. T, Hagman K. E., Shafer W. M. 1997; The MtrR repressor binds the DNA sequence between the mtrR and mtrC genes of Neisseria gonorrhoeae . J Bacteriol 179:4123–4128
    [Google Scholar]
  16. Ma D, Alberti M, Lynch C, Nikaido H., Hearst J. E. 1996; The local repressor AcrR plays a modulating role in the regulation of acrAB genes of Escherichia coli by global stress signals. Mol Microbiol 19:101–112
    [Google Scholar]
  17. Mahairas G. G, Sabo P. J, Hickey M. J, Singh D. C., Stover C. K. 1996; Molecular analysis of genetic differences between Mycobacterium bovis BCG and virulent M. bovis . J Bacteriol 178:1274–1282
    [Google Scholar]
  18. Miller J. H. 1972 Experiments in Molecular Genetics Cold Spring Harbor, NY: Cold Spring Harbor Laboratory;
    [Google Scholar]
  19. Mulder M. A, Zappe H., Steyn L. M. 1997; Mycobacterial promoters. Tuber Lung Dis 78:211–223
    [Google Scholar]
  20. Murray C. J. L, Styblo K., Rouillon A. 1990; Tuberculosis in developing countries: burden, intervention and cost. Bull Int Union Tuberc Lung Dis 65:6–24
    [Google Scholar]
  21. Namwat W, Lee C. K, Kinoshita H, Yamada Y., Nihira T. 2001; Identification of the varR gene as a transcriptional regulator of virginiamycin S resistance in Streptomyces virginiae . J Bacteriol 183:2025–2031
    [Google Scholar]
  22. Orth P, Schnappinger D, Hillen W, Saenger W., Hinrichs W. 2000; Structural basis of gene regulation by the tetracycline inducible Tet repressor–operator system. Nat Struct Biol 7:215–219
    [Google Scholar]
  23. Parish T., Stoker N. G. 1998; Electroporation of mycobacteria. In Mycobacteria Protocols. Methods in Molecular Biology vol. 101 pp 120–144 Totowa, New Jersey: Humana Press;
    [Google Scholar]
  24. Parker S. L, Tsai Y. L., Palmer C. J. 1995; Comparison of PCR-generated fragments of the mce gene from Mycobacterium tuberculosis, M. avium, M. intracellulare, and M. scrofulaceum . Clin Diagn Lab Immunol 2:770–775
    [Google Scholar]
  25. Rkenes T. P, Lamark T., Strom A. R. 1996; DNA-binding properties of the BetI repressor protein of Escherichia coli : the inducer choline stimulates BetI–DNA complex formation. J Bacteriol 178:1663–1670
    [Google Scholar]
  26. Rouch D. A, Cram D. S, DiBerardino D, Littlejohn T. G., Skurray R. A. 1990; Efflux-mediated antiseptic resistance gene qacA from Staphylococcus aureus : common ancestry with tetracycline- and sugar-transport proteins. Mol Microbiol 4:2051–2062
    [Google Scholar]
  27. Smith H. 1984; The biochemical challenge of microbial pathogenicity. J Appl Bacteriol 47:395–404
    [Google Scholar]
  28. Timm J, Lim E. M., Gicquel B. 1994; Escherichia coli –mycobacteria shuttle vectors for operon and gene fusion to lacZ : the pJEM series. J Bacteriol 176:6749–6753
    [Google Scholar]
  29. van Soolingen D, Hermans P. W. M, de Haas P. E. W, Soll D. R., van Embden J. D. A. 1991; Occurrence and stability of insertion sequences in Mycobacterium tuberculosis complex strains: evaluation of an insertion sequence-dependent DNA polymorphism as a tool in the epidemiology of tuberculosis. J Clin Microbiol 29:2578–2586
    [Google Scholar]
  30. Zumarraga M, Bigi F, Alito A, Romano M. I., Cataldi A. 1999; A 12·7 kb fragment of Mycobacterium tuberculosis genome is not present in Mycobacterium bovis . Microbiology 145:893–897
    [Google Scholar]
http://instance.metastore.ingenta.com/content/journal/micro/10.1099/00221287-148-10-2997
Loading
/content/journal/micro/10.1099/00221287-148-10-2997
Loading

Data & Media loading...

Most cited Most Cited RSS feed