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Publication Abstract from PubMed

Histidine kinase receptors are a large family of membrane-spanning proteins found in many prokaryotes and some eukaryotes. They are a part of two-component signal transduction systems, which each comprise a sensor kinase and a response regulator and are involved with the regulation of many cellular processes. NarX is a histidine kinase receptor that responds to nitrate and nitrite to effect regulation of anaerobic respiration in various bacteria. We present high-resolution X-ray crystal structures of the periplasmic sensor domain from Escherichia coli NarX in a complex with nitrate and in the apo state. Our analysis reveals that nitrate-binding induces conformation changes that result in a piston-type displacement between the N- and C-terminal helices of the periplasmic domain. Such conformational changes might represent a conserved mechanism of signaling in histidine kinases by which ligand binding is communicated across the lipid bilayer.

Structural Analysis of Ligand Stimulation of the Histidine Kinase NarX.,Cheung J, Hendrickson WA Structure. 2009 Feb 13;17(2):190-201. PMID:19217390^[1]

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.