2AN2

P332G, A333S Double mutant of the Bacillus subtilis Nitric Oxide Synthase

Summary for 2AN2

• Entry DOI: 10.2210/pdb2an2/pdb
• Related: 1M7Z 2ANO
• Descriptor: P332G A333S double mutant of Nitric Oxide Synthase from Bacillus subtilis, ARGININE, PROTOPORPHYRIN IX CONTAINING FE, ... (5 entities in total)
• Functional Keywords: double mutant, oxidoreductase
• Biological source: Bacillus subtilis
• Total number of polymer chains: 1
• Total formula weight: 42343.33

Authors

Pant, K.,Crane, B.R. (deposition date: 2005-08-11, release date: 2006-08-29, Last modification date: 2024-02-14)

Primary citation

Pant, K.,Crane, B.R.
Structure of a loose dimer: an intermediate in nitric oxide synthase assembly
J.Mol.Biol., 352:932-940, 2005

PubMed Abstract: Cooperativity among ligand binding, subunit association, and protein folding has implications for enzyme regulation as well as protein aggregation events associated with disease. The binding of substrate l-arginine or cofactor tetrahydrobiopterin converts nitric oxide synthases (NOSs) from a "loose dimer", with an exposed active center and higher sensitivity to proteolysis, to a "tight dimer" competent for catalysis. The crystallographic structure of the Bacillus subtilis NOS loose dimer shows an altered association state with severely destabilized subdomains. Ligand binding or heme reduction converts loose dimers to tight dimers in solution and crystals. Mutations at key positions in the dimer interface that distinguish prokaryotic from eukaryotic NOSs affect the propensity to form loose dimers. The loose dimer structure indicates that non-native interactions can mediate subunit association in NOS.

PubMed: 16126221
DOI: 10.1016/j.jmb.2005.07.070

Experimental method

X-RAY DIFFRACTION (2.6 Å)