Mce2R (Rv0586), a GntR-like transcriptional regulator from Mycobacterium tuberculosis, repress the expression of the virulence factors encoded in mce2 operon

BLANCO, F.; SANTANGELO, MP; KLEPP, L; BIANCO, V.; CATALDI, A; BIGI, F

Pinamar, Bs. As.

Congreso; XLI Reunión Anual de la Sociedad Argentina de Investigaciones Bioquímicas y de Biología Molecular; 2005

Sociedad Argentina de Investigaciones Bioquímicas

An invasin-like gene from  An invasin-like gene from Mycobacterium tuberculosis was first described that conferred the ability on non-pathogenic Escherichia coli to invade and survive within macrophages and human HeLa cells, and it was named the mammalian cell entry (mce) gene. Subsequently, the analysis of the complete sequence of the M. tuberculosis H37Rv genome revealed the presence of three additional paralogous mce genes, all encoding in an operon structures consisting of eight genes. The biological function of Mce proteins is not known, but increasing evidences have demonstrated that they are clearly related to the virulence of Mycobacterium tuberculosis complex species. Regulatory mechanism which control mce3 expression has been identified by our group. We have found that a TetR family transcriptional regulator down regulates mce3 operon during the in vitro growing of M. tuberculosis. Other putative gene encoding transcriptional factor, Rv0586, is located immediately upstream of mce2 operon. Here we report the initial characterization of Mce2R (Rv0586), a transcriptional regulator belonging from the GntR family. By using a promoter probe approach we found that Mce2R repress de expression of mce2 operon. The specific binding of recombinant Mce2R to the promoter region of mce2 operon was demonstrated by gel shift assay.