Reaction Mechanism
The mechanism of action has still not been entirely deduced, however, the leading theory suggests that the conversion is carried out through a series of redox reactions involving iron centers as shown in the series of half reactions below:
| Step | Reaction |
|---|---|
| FAD reduction | NAD(P)H + FAD + H+ → NAD(P)+ + FADH2 |
| Iron reduction 1 | FADH2 + Fe3+ → Fe2+ + FADH + H+ |
| Iron Reduction 2 | FADH + Fe3+ → FAD + Fe2+ + H+ |
| O2 Binding | Fe2+ + O2 → Fe3+(O2-) |
| NO dioxygenation | Fe3+(O2-) + NO → Fe3+ + NO3- |
Another theory developed more recently (2009) suggests that a NO dioxygenase activity could also proceed through phenolic nitration via a putative heme-peroxynitrite intermediate.
The most well studied NO dioxygenase is flavohemoglobin (flavoHb), shown to the right: Studies have shown that flavohemoglobins are induced by NO, nitrite, nitrate, and NO-releasing agents in various bacteria and fungi. Additionally, flavoHbs have been shown to protect bacteria, yeast, and Dictyostelium discoideum against growth inhibition and damage mediated via NO.
Read more about this topic: Nitric Oxide Dioxygenase
Famous quotes containing the words reaction and/or mechanism:
“Christianity was only a very strong and singularly well-timed Salvation Army movement that happened to receive help from an unusual and highly dramatic incident. It was a Puritan reaction in an age when, no doubt, a Puritan reaction was much wanted; but like all sudden violent reactions, it soon wanted reacting against.”
—Samuel Butler (1835–1902)
“The two elements the traveler first captures in the big city are extrahuman architecture and furious rhythm. Geometry and anguish. At first glance, the rhythm may be confused with gaiety, but when you look more closely at the mechanism of social life and the painful slavery of both men and machines, you see that it is nothing but a kind of typical, empty anguish that makes even crime and gangs forgivable means of escape.”
—Federico García Lorca (1898–1936)