Molecular interactions in the two-component system of the accessory gene regulator of Staphylococcus aureus

Two component systems are common response mechanism to extracellular stimuli in bacteria. Sensory element activation triggers ATP-dependent autophosphorylation and the recruitment of a downstream response mediating transcription factor. We propose to study the association between soluble catalytic domain from the accessory gene regulator in S. aureus, AgrC, and its downstream response partner, AgrA, responsible for modulation of virulence and collective bacterial behaviour. Deuterated components will be characterised in the presence of ATP or non-hydrolysable ATP analogues and the assembly of the complex will be monitored by SANS.