TP0262 is a modulator of promoter activity of tpr Subfamily II genes of Treponema pallidum ssp. pallidum
Article first published online: 30 APR 2009
© 2009 Blackwell Publishing Ltd
Volume 72, Issue 5, pages 1087–1099, June 2009
How to Cite
Giacani, L., Godornes, C., Puray-Chavez, M., Guerra-Giraldez, C., Tompa, M., Lukehart, S. A. and Centurion-Lara, A. (2009), TP0262 is a modulator of promoter activity of tpr Subfamily II genes of Treponema pallidum ssp. pallidum. Molecular Microbiology, 72: 1087–1099. doi: 10.1111/j.1365-2958.2009.06712.x
- Issue published online: 22 MAY 2009
- Article first published online: 30 APR 2009
- Accepted 18 April, 2009.
Transcriptional regulation in Treponema pallidum ssp. pallidum is poorly understood, primarily because this organism cannot be cultivated in vitro or genetically manipulated. We have recently shown a phase variation mechanism controlling transcription initiation of Subfamily II tpr (T. pallidumrepeat) genes (tprE, tprG and tprJ), a group of virulence factor candidates. Furthermore, the same study suggested that additional mechanisms might influence the level of transcription of these tprs. The T. pallidum genome sequence has revealed a few open reading frames with similarity to known bacterial transcription factors, including four catabolite activator protein homologues. In this work, sequences matching the Escherichia coli cAMP receptor protein (CRP) binding motif were identified in silico upstream of tprE, tprG and tprJ. Using elecrophoretic mobility shift assay and DNaseI footprinting assay, recombinant TP0262, a T. pallidum CRP homologue, was shown to bind specifically to amplicons obtained from the tpr promoters containing putative CRP binding motifs. Using a heterologous reporter system, binding of TP0262 to these promoters was shown to either increase (tprE and tprJ) or decrease (tprG) tpr promoter activity. This is the first characterization of a T. pallidum transcriptional modulator that influences tpr promoter activity.