ausblenden:
Schlagwörter:
EPR; electron paramagnetic resonance; MCD; magnetic circular dichroism; N2OR; nitrous oxide reductase; Anaerobic respiration; ApbE protein family; Catalytic Cu center; CuA center biogenesis; N2O reductase activity
Zusammenfassung:
The effect of loss of the 34‐kDa periplasmic NosX protein on the properties of N2O reductase was investigated with an N2O‐respiration negative, double mutant of the paralogous genes nosX and nirX of Paracoccus denitrificans. In spite of absence of whole‐cell N2O‐reducing activity, the purified reductase was catalytically active, which attributes NosX a physiological role in sustaining the reaction cycle. N2O reductase exhibited the spectroscopic features of CuA and the redox‐inert, paramagnetic state, Cuz*, of the catalytic center. Cuz*, hitherto considered the result of spontaneous reaction of the reductase with dioxygen, attains cellular significance.
