1chn
MAGNESIUM BINDING TO THE BACTERIAL CHEMOTAXIS PROTEIN CHEY RESULTS IN LARGE CONFORMATIONAL CHANGES INVOLVING ITS FUNCTIONAL SURFACE
OverviewOverview
The three-dimensional crystal structure of the bacterial chemotaxis protein CheY with the essential Mg2+ cation bound to the active site reveals large conformational changes caused by the metal binding. Displacements of up to 10 A are observed in several residues at the N terminus of alpha-helix 4 and in the preceding loop. One turn of this helix unwinds, and an Asn residue that was located inside the helix becomes the new N-cap. This supports the important role that N or C-cap residues play in alpha-helix stability. In addition the preceding beta-strand becomes elongated and a new beta-turn appears. The final effect is a significant modification of the surface relief of the protein in a region previously indicated, by genetic analysis, to be essential for CheY function. It is suggested that binding of a divalent cation to CheY could play a significant part in CheY activation and consequently in signal transduction in prokaryotes.
About this StructureAbout this Structure
1CHN is a Single protein structure of sequence from Escherichia coli. Full crystallographic information is available from OCA.
ReferenceReference
Magnesium binding to the bacterial chemotaxis protein CheY results in large conformational changes involving its functional surface., Bellsolell L, Prieto J, Serrano L, Coll M, J Mol Biol. 1994 May 13;238(4):489-95. PMID:8176739 Page seeded by OCA on Fri May 2 12:44:29 2008