gnal transduction in bacteria: An integrative approach studying two-component signaling proteins, their interaction partners and their activation mechanism

To sample their environment and coordinate appropriate adaptation responses bacteria require a flurry of signal transduction systems. Among the most commonly utilized are the so-called two-component systems. These systems comprise (1) a sensor protein, the sensor histidine kinase which modulates an intrinsic autophosporylation activity in response to changing cellular and environmental clues and (2) a response regulator protein that interacts with DNA, RNA or protein targets to coordinate an appropriate response. This talk will discuss our recent findings studying selected systems in the Gram-positive model organism Bacillus subtilis by integrating information derived from a diverse set of experimental approaches such as genetics, enzymology and structural biology and in silico approaches such as Molecular Dynamics Simulations and Bioinformatic techniques. These studies identified some general rules by which these proteins coordinate a response on the molecular level, of relevance to all two-component systems and beyond. One system in particular, the YycFG system is conserved across the Gram-positives and essential for viability. Our studies have identified this system as a coordinator of cell division with cell wall homeostasis. This process involves numerous interactions with cellular protein components such as member of cell division. Some of these interactions have now been characterized genetically and structurally. Results and implications of these studies are discussed