Structural highlights
Function
NOR_FUSOX Nitric oxide reductase which is involved in a dissimilatory reduction of nitrite. Acts as a nitric oxide reductase. Is able to reduce nitrate and nitrite to a gaseous form of N(2)O when oxygen supply is limited or discontinued. May function as a detoxification mechanism.[1] [2]
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 PubMed
Arg and Lys residues are concentrated on the distal side of cytochrome P450nor (P450nor) to form a positively charged cluster facing from the outside to the inside of the distal heme pocket. We constructed mutant proteins in which the Arg and Lys residues were replaced with Glu, Gln, or Ala. The results showed that this cluster plays crucial roles in NADH interaction. We also showed that some anions such as bromide (Br(-)) perturbed the heme environment along with the reduction step in P450nor-catalyzed reactions, which was similar to the effects caused by the mutations. We determined by x-ray crystallography that a Br(-), termed an anion hole, occupies a key region neighboring heme, which is the terminus of the positively charged cluster and the terminus of the hydrogen bond network that acts as a proton delivery system. A comparison of the predicted mechanisms between the perturbations caused by Br(-) and the mutations suggested that Arg(174) and Arg(64) play a crucial role in binding NADH to the protein. These results indicated that the positively charged cluster is the unique structure of P450nor that responds to direct interaction with NADH.
A positively charged cluster formed in the heme-distal pocket of cytochrome P450nor is essential for interaction with NADH.,Kudo T, Takaya N, Park SY, Shiro Y, Shoun H J Biol Chem. 2001 Feb 16;276(7):5020-6. Epub 2000 Nov 13. PMID:11076941[3]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
See Also
References
- ↑ Shoun H, Tanimoto T. Denitrification by the fungus Fusarium oxysporum and involvement of cytochrome P-450 in the respiratory nitrite reduction. J Biol Chem. 1991 Jun 15;266(17):11078-82. PMID:2040619
- ↑ Zhang L, Kudo T, Takaya N, Shoun H. The B' helix determines cytochrome P450nor specificity for the electron donors NADH and NADPH. J Biol Chem. 2002 Sep 13;277(37):33842-7. Epub 2002 Jul 8. PMID:12105197 doi:http://dx.doi.org/10.1074/jbc.M203923200
- ↑ Kudo T, Takaya N, Park SY, Shiro Y, Shoun H. A positively charged cluster formed in the heme-distal pocket of cytochrome P450nor is essential for interaction with NADH. J Biol Chem. 2001 Feb 16;276(7):5020-6. Epub 2000 Nov 13. PMID:11076941 doi:10.1074/jbc.M007244200
