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2nsi
From Proteopedia
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HUMAN INDUCIBLE NITRIC OXIDE SYNTHASE, ZN-FREE, SEITU COMPLEX
Contents |
Overview
The crystal structures of the heme domain of human inducible nitric-oxide synthase (NOS-2) in zinc-free and -bound states have been solved. In the zinc-free structure, two symmetry-related cysteine residues form a disulfide bond. In the zinc-bound state, these same two cysteine residues form part of a zinc-tetrathiolate (ZnS(4)) center indistinguishable from that observed in the endothelial isoform (NOS-3). As in NOS-3, ZnS(4) plays a key role in stabilizing intersubunit contacts and in maintaining the integrity of the cofactor (tetrahydrobiopterin) binding site of NOS-2. A comparison of NOS-2 and NOS-3 structures illustrates the conservation of quaternary structure, tertiary topology, and substrate and cofactor binding sites, in addition to providing insights on isoform-specific inhibitor design. The structural comparison also reveals that pterin binding does not preferentially stabilize the dimer interface of NOS-2 over NOS-3.
Disease
Known diseases associated with this structure: Hypertension, susceptibility to OMIM:[163730], Malaria, resistance to OMIM:[163730]
About this Structure
2NSI is a Single protein structure of sequence from Homo sapiens with , , and as ligands. Active as Nitric-oxide synthase, with EC number 1.14.13.39 Full crystallographic information is available from OCA.
Reference
Crystal structures of zinc-free and -bound heme domain of human inducible nitric-oxide synthase. Implications for dimer stability and comparison with endothelial nitric-oxide synthase., Li H, Raman CS, Glaser CB, Blasko E, Young TA, Parkinson JF, Whitlow M, Poulos TL, J Biol Chem. 1999 Jul 23;274(30):21276-84. PMID:10409685
Page seeded by OCA on Thu Feb 21 18:10:27 2008
Categories: Homo sapiens | Nitric-oxide synthase | Single protein | Blasko, E. | Glaser, C B. | Li, H. | Parkinson, J F. | Poulos, T L. | Raman, C S. | Whitlow, M. | Young, T A. | H4B | HEM | ITU | SO4 | Heme protein | Nitric oxide synthase | Tetrahydrobiopterin
