1mmv
Rat neuronal NOS heme domain with NG-propyl-L-arginine boundRat neuronal NOS heme domain with NG-propyl-L-arginine bound
Structural highlights
FunctionNOS1_RAT Produces nitric oxide (NO) which is a messenger molecule with diverse functions throughout the body. In the brain and peripheral nervous system, NO displays many properties of a neurotransmitter. Inhibitory transmitter for non-adrenergic and non-cholinergic nerves in the colorectum. Probably has nitrosylase activity and mediates cysteine S-nitrosylation of cytoplasmic target proteins such SRR. Inhibitory transmitter for non-adrenergic and non-cholinergic nerves in the colorectum. Evolutionary Conservation![]() Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf. Publication Abstract from PubMedIsoform-specific nitric-oxide synthase (NOS) inhibitors may prove clinically useful in reducing the pathophysiological effects associated with increased neuronal NOS (nNOS) or inducible NOS (iNOS) activity in a variety of neurological and inflammatory disorders. Analogs of the NOS substrate L-arginine are pharmacologically attractive inhibitors because of their stability, reliable cell uptake, and good selectivity for NOS over other heme proteins. Some inhibitory arginine analogs show significant isoform selectivity although the structural or mechanistic basis of such selectivity is generally poorly understood. In the present studies, we determined by x-ray crystallography the binding interactions between rat nNOS and N5-(1-imino-3-butenyl)-L-ornithine (L-VNIO), a previously identified mechanism-based, irreversible inactivator with moderate nNOS selectivity. We have also synthesized and mechanistically characterized several L-VNIO analogs and find, surprisingly, that even relatively minor structural changes produce inhibitors that are either iNOS-selective or non-selective. Furthermore, derivatives having a methyl group added to the butenyl moiety of L-VNIO and L-VNIO derivatives that are analogs of homoarginine rather than arginine display slow-on, slow-off kinetics rather than irreversible inactivation. These results elucidate some of the structural requirements for isoform-selective inhibition by L-VNIO and its related alkyl- and alkenyl-imino ornithine and lysine derivatives and may provide information useful in the ongoing rational design of isoform-selective inhibitors. Structural characterization and kinetics of nitric-oxide synthase inhibition by novel N5-(iminoalkyl)- and N5-(iminoalkenyl)-ornithines.,Bretscher LE, Li H, Poulos TL, Griffith OW J Biol Chem. 2003 Nov 21;278(47):46789-97. Epub 2003 Sep 5. PMID:12960153[1] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See AlsoReferences
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