Figure 5.

CPK model of the N-terminal domain of CheB, showing surfaces that are involved in protein–protein interactions among the response regulators CheB, CheY, and NarL. Residues involved in interaction with the C-terminal domain of CheB are colored yellow. Residues that have been implicated in protein–protein interactions in other response regulators are shown with colored mesh: red for corresponding residues in CheY that are thought to be involved in interaction with the P2 domain of the histidine kinase CheA (39); green for corresponding residues in NarL that interact with its C-terminal DNA-binding domain (25).