3NSE

BOVINE ENOS, H4B-FREE, SEITU COMPLEX

Summary for 3NSE

• Entry DOI: 10.2210/pdb3nse/pdb
• Descriptor: NITRIC OXIDE SYNTHASE, ACETATE ION, CACODYLATE ION, ... (9 entities in total)
• Functional Keywords: nitric oxide synthase, heme protein, tetrahydrobiopterin, complex (oxidoreductase-peptide), complex (oxidoreductase-peptide) complex, complex (oxidoreductase/peptide)
• Biological source: Bos taurus (cattle)
• Cellular location: Cell membrane: P29473
• Total number of polymer chains: 2
• Total formula weight: 101888.59

Authors

Raman, C.S.,Li, H.,Martasek, P.,Kral, V.,Masters, B.S.S.,Poulos, T.L. (deposition date: 1998-09-23, release date: 1999-05-18, Last modification date: 2024-02-21)

Primary citation

Raman, C.S.,Li, H.,Martasek, P.,Kral, V.,Masters, B.S.,Poulos, T.L.
Crystal structure of constitutive endothelial nitric oxide synthase: a paradigm for pterin function involving a novel metal center.
Cell(Cambridge,Mass.), 95:939-950, 1998

PubMed Abstract: Nitric oxide, a key signaling molecule, is produced by a family of enzymes collectively called nitric oxide synthases (NOS). Here, we report the crystal structure of the heme domain of endothelial NOS in tetrahydrobiopterin (H4B)-free and -bound forms at 1.95 A and 1.9 A resolution, respectively. In both structures a zinc ion is tetrahedrally coordinated to pairs of symmetry-related cysteine residues at the dimer interface. The phylogenetically conserved Cys-(X)4-Cys motif and its strategic location establish a structural role for the metal center in maintaining the integrity of the H4B-binding site. The unexpected recognition of the substrate, L-arginine, at the H4B site indicates that this site is poised to stabilize a positively charged pterin ring and suggests a model involving a cationic pterin radical in the catalytic cycle.

PubMed: 9875848
DOI: 10.1016/S0092-8674(00)81718-3

Experimental method

X-RAY DIFFRACTION (2.1 Å)