CONICET | Buscador de Institutos y Recursos Humanos

Anthrax, a potentially fatal disease of animals and humans, is caused by the Gram-positive endospore-forming bacterium Bacillus anthracis. The anthrax toxin is one of its major virulence determinants. The toxin genes are coordinately regulated at the level of transcription and are induced by bicarbonate and increase in temperature, but the mechanism of thermal regulation remains unsolved. In this study we examined two genes located in B.anthracis chromosome, BA5597-BA5598, as they present high homology with B. subtilis DesK-DesR two component system, which regulates transcription of its sole desaturase in response to environmental temperature changes. According to this, we carried out in vitro experiments to asses the autokinase activity of a cytoplasmic N-terminal truncated form of the potential histidine- kinase, BA5598C, and its ability to phosphorilate its cognate response regulator, BA5597. We also observed crosstalk capability between DesKC and BA5597. Currently, we are analyzing B. subtilis strains that lack DesK to evaluate if expression of BA5598 restores the ability of the mutant to transcribe the des gene at low temperature.This will mean that the B. anthracis kinase is responding to the same signal sensed by DesK, and would support a more general role of these TCSs in G+ bacteria.