2kii

Publication Abstract from PubMed

Heme nitric oxide/oxygen (H-NOX) proteins are found in eukaryotes where they are typically part of a larger protein such as soluble guanylate cyclase and in prokaryotes where they are often found in operons with a histidine kinase, suggesting that H-NOX proteins serve as sensors for NO and O(2) in signaling pathways. The Fe(II)-NO complex of the H-NOX protein from Shewanella oneidensis inhibits the autophosphorylation of the operon-associated histidine kinase, whereas the ligand-free H-NOX has no effect on the kinase. NMR spectroscopy was used to determine the structures of the Fe(II)-CO complex of the S. oneidensis H-NOX and the Fe(II)-CO complex of the H103G H-NOX mutant as a mimic of the ligand-free and kinase-inhibitory Fe(II)-NO H-NOX, respectively. The results provide a molecular glimpse into the ligand-induced conformational changes that may underlie kinase inhibition and the subsequent control of downstream signaling.

A structural basis for H-NOX signaling in Shewanella oneidensis by trapping a histidine kinase inhibitory conformation.,Erbil WK, Price MS, Wemmer DE, Marletta MA Proc Natl Acad Sci U S A. 2009 Nov 24;106(47):19753-60. Epub 2009 Nov 16. PMID:19918063^[1]

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