Coevolved residues in dimeric interface of OmpR/PhoB family.

<p>(A) Sequence conservation of the α4β5α5 dimeric interface of RegX3, PhoB, TorR and YycF in OmpR/PhoB family. Residues are numbered according to RegX3 and colored based on chemistry: acidic in red, basic in blue, hydrophobic in black, polar in green and neutral in purple. Coevolved pairs are under-dotted with the same colors. (B-E) Active state structures of RegX3 (2OQR), TorR (1ZGZ), PhoB (1ZES) and YycF (1NXP) in OmpR/PhoB family with coevolved residues in dimeric interface highlighted in sticks. It is noteworthy that RegX3 forms a complete dimeric structure with swapped domains that are colored in light and dark greys.