Figure 6.

A typical receptor-kinase signaling complex illustrated by the aspartate receptor. The transmembrane receptor provides the architectural framework of the super-molecular signaling complex (Borkovich et al 1989, Ninfa et al 1991, Gegner et al 1992, Schuster et al 1993, Wu et al 1996). Most of the chemosensory pathway components are associated with this complex, either stably or transiently. The kinetically stable core ternary complex is composed of the dimeric receptor (illustrated as a collection of helices), the coupling protein CheW, and the dimeric histidine kinase CheA. Other components are believed to be in rapid equilibrium between bound and soluble forms, including periplasmic binding proteins, the methyltransferase CheR, the methylesterase CheB, and the motor response regulator CheY.