1XQD

Crystal structure of P450NOR complexed with 3-pyridinealdehyde adenine dinucleotide

Summary for 1XQD

• Entry DOI: 10.2210/pdb1xqd/pdb
• Related: 1ULW
• Descriptor: CYTOCHROME P450 55A1, PROTOPORPHYRIN IX CONTAINING FE, NICOTINIC ACID ADENINE DINUCLEOTIDE, ... (4 entities in total)
• Functional Keywords: nitric oxide reductase, cytochrome p450nor, nadh complex, oxidoreductase
• Biological source: Fusarium oxysporum
• Total number of polymer chains: 1
• Total formula weight: 45641.57

Authors

Oshima, R.,Fushinobu, S.,Takaya, N.,Su, F.,Wakagi, T.,Shoun, H. (deposition date: 2004-10-12, release date: 2004-10-26, Last modification date: 2023-10-25)

Primary citation

Oshima, R.,Fushinobu, S.,Su, F.,Zhang, L.,Takaya, N.,Shoun, H.
Structural evidence for direct hydride transfer from NADH to cytochrome P450nor
J.Mol.Biol., 342:207-217, 2004

PubMed Abstract: Nitric oxide reductase cytochrome P450nor catalyzes an unusual reaction, direct electron transfer from NAD(P)H to bound heme. Here, we succeeded in determining the crystal structure of P450nor in a complex with an NADH analogue, nicotinic acid adenine dinucleotide, which provides conclusive evidence for the mechanism of the unprecedented electron transfer. Comparison of the structure with those of dinucleotide-free forms revealed a global conformational change accompanied by intriguing local movements caused by the binding of the pyridine nucleotide. Arg64 and Arg174 fix the pyrophosphate moiety upon the dinucleotide binding. Stereo-selective hydride transfer from NADH to NO-bound heme was suggested from the structure, the nicotinic acid ring being fixed near the heme by the conserved Thr residue in the I-helix and the upward-shifted propionate side-chain of the heme. A proton channel near the NADH channel is formed upon the dinucleotide binding, which should direct continuous transfer of the hydride and proton. A salt-bridge network (Glu71-Arg64-Asp88) was shown to be crucial for a high catalytic turnover.

PubMed: 15313618
DOI: 10.1016/j.jmb.2004.07.009

Experimental method

X-RAY DIFFRACTION (1.8 Å)