Nucleotide binding by the histidine kinase CheA.
Bilwes, A.M., Quezada, C.M., Croal, L.R., Crane, B.R., Simon, M.I.(2001) Nat Struct Biol 8: 353-360
- PubMed: 11276258 
- DOI: https://doi.org/10.1038/86243
- Primary Citation of Related Structures:  
1I58, 1I59, 1I5A, 1I5B, 1I5C, 1I5D - PubMed Abstract: 
To probe the structural basis for protein histidine kinase (PHK) catalytic activity and the prospects for PHK-specific inhibitor design, we report the crystal structures for the nucleotide binding domain of Thermotoga maritima CheA with ADP and three ATP analogs (ADPNP, ADPCP and TNP-ATP) bound with either Mg(2+) or Mn(2+). The conformation of ADPNP bound to CheA and related ATPases differs from that reported in the ADPNP complex of PHK EnvZ. Interactions of the active site with the nucleotide gamma-phosphate and its associated Mg(2+) ion are linked to conformational changes in an ATP-lid that could mediate recognition of the substrate domain. The inhibitor TNP-ATP binds CheA with its phosphates in a nonproductive conformation and its adenine and trinitrophenyl groups in two adjacent binding pockets. The trinitrophenyl interaction may be exploited for designing CheA-targeted drugs that would not interfere with host ATPases.
Organizational Affiliation: 
Division of Biology, California Institute of Technology, 1200 East California Blvd., Pasadena, California 91125, USA.