Differential expression of a virulence factor in pathogenic and non-pathogenic mycobacteria

Houben, E. N. G. and Walburger, A. and Ferrari, G. and Nguyen, L. and Thompson, C. J. and Miess, C. and Vogel, G. and Mueller, B. and Pieters, J.. (2009) Differential expression of a virulence factor in pathogenic and non-pathogenic mycobacteria. Molecular Microbiology, 72 (1). pp. 41-52.

[img] PDF
Restricted to Repository staff only


Official URL: http://edoc.unibas.ch/dok/A5259379

Downloads: Statistics Overview


The pathogenicity of mycobacterial infections depends on virulence factors that mediate survival inside host macrophages. These virulence factors are generally believed to be specific for pathogenic species and absent or mutated in non-pathogenic strains. The serine/threonine protein kinase G (PknG) mediates survival of mycobacteria within macrophages by blocking lysosomal delivery. Here we describe a gene of the non-pathogenic species Mycobacterium smegmatis that is 78% identical with pknG of Mycobacterium tuberculosis and M. bovis bacillus Calmette-Guerin (BCG). When cloned into expression vectors, the M. smegmatis pknG orthologue produced an active kinase and performed the same function as its M. bovis BCG counterpart in intracellular survival. In addition, similar levels of pknG transcripts were found in M. bovis BCG and M. smegmatis. However, virtually no translation product of chromosomal pknG could be detected in M. smegmatis both after in vitro growth and after macrophage infection. This lack of efficient translation was shown to be caused by regulatory elements in the upstream region of the M. smegmatis gene. The data reveal dramatically increased translational efficiency of a virulence gene in a pathogenic mycobacterium compared with a non-pathogenic mycobacterium suggesting that changes in expression levels may underlie evolution of pknG and other pathogenicity genes in mycobacterium.
Faculties and Departments:05 Faculty of Science > Departement Biozentrum > Infection Biology > Biochemistry (Pieters)
UniBasel Contributors:Pieters, Jean
Item Type:Article, refereed
Article Subtype:Research Article
Note:Publication type according to Uni Basel Research Database: Journal article
Identification Number:
edoc DOI:
Last Modified:04 Oct 2017 15:15
Deposited On:22 Mar 2012 13:22

Repository Staff Only: item control page