The structure of a ternary complex between CheA domains P4 and P5 with CheW and with an unzipped fragment of TM14, a chemoreceptor analog from Thermotoga maritima.

The 3.2 angstrom resolution structure of a receptor: CheA:CheW signaling complex defines overlapping binding sites and key residue interactions within bacterial chemosensory arrays.

Methyl-accepting chemotaxis sensory transducer, Chemoreceptor Tm00014

Cubic shaped crystals (50x50x50 um3) were grown from a mixture of 520 uM Tm14s, 457 uM CheA 354 and 121 uM CheW after 1 month by vapor diffusion from a 2 ul drop (1:1 mixture of protein and reservoir: 500 ul reservoir of 0.2 M sodium acetate trihydrate, 0.1 M Tris (pH 8.5), 15% w/v polyethylene glycol 4,000), VAPOR DIFFUSION, HANGING DROP, temperature 298K

Chemotaxis protein CheA (E.C.2.7.13.3), Chemotaxis protein CheW, Methyl-accepting chemotaxis protein

The receptor fragment is dimerized by crystal symmetry to produce a 4-helix bundle. The assembly state of the receptor kinase arrays is complex and extended, but the ring structure formed by the alternating CheA and CheW units built by the crystal symmetry of this structure are thought to be important features of the assembled system.

Ternary complex, Transmembrane Signaling Two component system Receptor, Histidine Kinase Adaptor protein, Membrane, IMMUNE SYSTEM