1887

Abstract

Phosphoenolpyruvate carboxykinase (PEPCK) catalyses the reversible decarboxylation and phosphorylation of oxaloacetate (OAA) to form phosphoenolpyruvate (PEP). In this study, the regulation of the PEPCK-encoding gene was examined through the evaluation of green fluorescent protein expression driven by the promoter. The results showed that was upregulated by acetate or palmitate but downregulated by glucose. Deletion of the gene of BCG led to a reduction in the capacity of the bacteria to infect and survive in macrophages. Moreover, mice infected with Δ BCG were able to reduce the bacterial load much more effectively than mice infected with the parental wild-type bacteria. This attenuated virulence was reflected in the degree of pathology, where granuloma formation was diminished both in numbers and degree. The data indicate that PEPCK activity is important during establishment of infection. Whether its role is in the gluconeogenic pathway for carbohydrate formation or in the conversion of PEP to OAA to maintain the TCA cycle remains to be determined.

Loading

Article metrics loading...

/content/journal/micro/10.1099/mic.0.26234-0
2003-07-01
2019-10-14
Loading full text...

Full text loading...

/deliver/fulltext/micro/149/7/mic1491829.html?itemId=/content/journal/micro/10.1099/mic.0.26234-0&mimeType=html&fmt=ahah

References

  1. Barbieri, J. T., Austin, F. E. & Cox, C. D. ( 1981; ). Distribution of glucose incorporated into macromolecular material by Treponema pallidum. Infect Immun 31, 1071–1077.
    [Google Scholar]
  2. Collins, D. M., Wilson, T., Campbell, S., Buddle, B. M., Wards, B. J., Hotter, G. & de Lisle, G. W. ( 2002; ). Production of avirulent mutants of Mycobacterium bovis with vaccine properties by the use of illegitimate recombination and screening of stationary-phase cultures. Microbiology 148, 3019–3027.
    [Google Scholar]
  3. Cymeryng, C., Cazzulo, J. J. & Cannata, J. J. ( 1995; ). Phosphoenolpyruvate carboxykinase from Trypanosoma cruzi. Purification and physicochemical and kinetic properties. Mol Biochem Parasitol 73, 91–101.[CrossRef]
    [Google Scholar]
  4. Hou, S. Y., Chao, Y. P. & Liao, J. C. ( 1995; ). A mutant phosphoenolpyruvate carboxykinase in Escherichia coli conferring oxaloacetate decarboxylase activity. J Bacteriol 177, 1620–1623.
    [Google Scholar]
  5. Liu, K., Zinker, S., Arguello, C. & Salgado, L. M. ( 2000; ). Isolation and analysis of a new developmentally regulated gene from amastigotes of Leishmania mexicana mexicana. Parasitol Res 86, 140–150.[CrossRef]
    [Google Scholar]
  6. McKinney, J. D., Honer zu Bentrup, K., Munoz-Elias, E. J. & 7 other authors ( 2000; ). Persistence of Mycobacterium tuberculosis in macrophages and mice requires the glyoxylate shunt enzyme isocitrate lyase. Nature 406, 735–738.[CrossRef]
    [Google Scholar]
  7. Mukhopadhyay, B., Concar, E. M. & Wolfe, R. S. ( 2001; ). A GTP-dependent vertebrate-type phosphoenolpyruvate carboxykinase from Mycobacterium smegmatis. J Biol Chem 276, 16137–16145.[CrossRef]
    [Google Scholar]
  8. Osteras, M., Finan, T. M. & Stanley, J. ( 1991; ). Site-directed mutagenesis and DNA sequence of pckA of Rhizobium NGR234, encoding phosphoenolpyruvate carboxykinase: gluconeogenesis and host-dependent symbiotic phenotype. Mol Gen Genet 230, 257–269.[CrossRef]
    [Google Scholar]
  9. Pelicic, V., Reyrat, J. M. & Gicquel, B. ( 1996; ). Generation of unmarked directed mutations in mycobacteria, using sucrose counter-selectable suicide vectors. Mol Microbiol 20, 919–925.[CrossRef]
    [Google Scholar]
  10. Rohrer, S. P., Saz, H. J. & Nowak, T. ( 1986; ). Purification and characterization of phosphoenolpyruvate carboxykinase from the parasitic helminth Ascaris suum. J Biol Chem 261, 13049–13055.
    [Google Scholar]
  11. Schocke, L. & Weimer, P. J. ( 1997; ). Purification and characterization of phosphoenolpyruvate carboxykinase from the anaerobic ruminal bacterium Ruminococcus flavefaciens. Arch Microbiol 167, 289–294.[CrossRef]
    [Google Scholar]
  12. Scovill, W. H., Schreier, H. J. & Bayles, K. W. ( 1996; ). Identification and characterization of the pckA gene from Staphylococcus aureus. J Bacteriol 178, 3362–3364.
    [Google Scholar]
  13. Smith, C. V., Huang, C. C., Miczak, A., Russell, D. G., Sacchettini, J. C. & Honer zu Bentrup, K. ( 2003; ). Biochemical and structural studies of malate synthase from Mycobacterium tuberculosis. J Biol Chem 278, 1735–1743.[CrossRef]
    [Google Scholar]
http://instance.metastore.ingenta.com/content/journal/micro/10.1099/mic.0.26234-0
Loading
/content/journal/micro/10.1099/mic.0.26234-0
Loading

Data & Media loading...

This is a required field
Please enter a valid email address
Approval was a Success
Invalid data
An Error Occurred
Approval was partially successful, following selected items could not be processed due to error