PMID: 12954642 , Related PDB ids: 1QW4, 1QW5, 1QW6, 1QWC

Authors:

Fedorov R, Hartmann E, Ghosh DK, Schlichting I

Title:

Structural basis for the specificity of the nitric-oxide synthase inhibitors W1400 and Nomega-propyl-L-Arg for the inducible and neuronal isoforms.

Journal:

J Biol Chem. 2003 Nov 14;278(46):45818-25. Epub 2003 Sep 3.

Abstract:

The high level of amino acid conservation and structural similarity in the immediate vicinity of the substrate binding sites of the oxygenase domains of the nitric-oxide synthase (NOS) isoforms (eNOSoxy, iNOSoxy, and nNOSoxy) make the interpretation of the structural basis of inhibitor isoform specificity a challenge and provide few clues for the design of new selective compounds. Crystal structures of iNOSoxy and nNOSoxy complexed with the inhibitors W1400 and Nomega-propyl-l-arginine provide a rationale for their isoform specificity. It involves differences outside the immediate active site as well as a conformational flexibility in the active site that allows the adoption of distinct conformations in response to interactions with the inhibitors. This flexibility is determined by isoform-specific residues outside the active site.