1nos

Publication Abstract from PubMed

The nitric oxide synthase oxygenase domain (NOSox) oxidizes arginine to synthesize the cellular signal and defensive cytotoxin nitric oxide (NO). Crystal structures determined for cytokine-inducible NOSox reveal an unusual fold and heme environment for stabilization of activated oxygen intermediates key for catalysis. A winged beta sheet engenders a curved alpha-beta domain resembling a baseball catcher's mitt with heme clasped in the palm. The location of exposed hydrophobic residues and the results of mutational analysis place the dimer interface adjacent to the heme-binding pocket. Juxtaposed hydrophobic O2- and polar L-arginine-binding sites occupied by imidazole and aminoguanidine, respectively, provide a template for designing dual-function inhibitors and imply substrate-assisted catalysis.

The structure of nitric oxide synthase oxygenase domain and inhibitor complexes.,Crane BR, Arvai AS, Gachhui R, Wu C, Ghosh DK, Getzoff ED, Stuehr DJ, Tainer JA Science. 1997 Oct 17;278(5337):425-31. PMID:9334294^[2]

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