Reactions of ferrous neuroglobin and cytoglobin with nitrite under anaerobic conditions.

摘要: Recent evidence suggests that the reaction of nitrite with deoxygenated hemoglobin and myoglobin contributes to generation nitric oxide S-nitrosothiols in vivo under conditions low oxygen availability. We have investigated whether ferrous neuroglobin cytoglobin, two hexacoordinate globins from vertebrates expressed brain a variety tissues, respectively, also react anaerobic conditions. Using absorption spectroscopy, we find second-order rate constant similar myoglobin, whereas heme cytoglobin does not nitrite. Deconvolution absorbance spectra shows that, course nitrite, ferric Fe(III) is generated excess nitrosyl Fe(II)-NO as due affinity for oxide. By using scavenger oxide, dissociates much faster than previously appreciated, consistently decay product during reaction. Both are S-nitrosated when reacting showing higher levels S-nitrosation. The possible biological significance between hypoxia discussed.