Format

Send to

Choose Destination
Microbiology. 2006 Sep;152(Pt 9):2749-56.

Regulation of the expression of whiB1 in Mycobacterium tuberculosis: role of cAMP receptor protein.

Author information

1
Department of Medicine, Johns Hopkins University, CRB2, Rm 1.08, 1550 Orleans Street, Baltimore, MD 21231-1044, USA.

Abstract

The wbl (whiB-like) genes encode putative transcription factors unique to actinomycetes. This study characterized the promoter element of one of the seven wbl genes of Mycobacterium tuberculosis, whiB1 (Rv3219c). The results reveal that whiB1 is transcribed by a class I-type cAMP receptor protein (CRP)-dependent promoter, harbouring a CRP-binding site positioned at -58.5 with respect to its transcription start point. In vivo promoter activity analysis and electrophoretic mobility shift assays suggest that the expression of whiB1 is indeed regulated by cAMP-dependent binding of CRP(M) (encoded by the M. tuberculosis gene Rv3676) to the whiB1 5' untranslated region (5'UTR). beta-Galactosidase gene fusion analysis revealed induction of the whiB1 promoter in M. tuberculosis on addition of exogenous dibutyric cAMP (a diffusible cAMP analogue) only when an intact CRP-binding site was present. These results indicate that M. tuberculosis whiB1 transcription is regulated in part by cAMP levels via direct binding of cAMP-activated CRP(M) to a consensus CRP-binding site in the whiB1 5'UTR.

PMID:
16946269
DOI:
10.1099/mic.0.28924-0
[Indexed for MEDLINE]

Supplemental Content

Full text links

Icon for Ingenta plc
Loading ...
Support Center