[CITATION][C] Superoxide radicals as precursors of mitochondrial hydrogen peroxide
G Loschen, A Azzi, C Richter, L Flohé - FEBS letters, 1974 - Wiley Online Library
G Loschen, A Azzi, C Richter, L Flohé
FEBS letters, 1974•Wiley Online LibraryA component of the mitochondrial respiratory chain located between the sites of the
antimycin and rotenone inhibition has been shown to produce considerable amounts of
H202 under certain conditions [l-4]. Since this part of the respiratory chain switches from two
electron transfer to one electron transfer H202 may be formed either directly by a two
electron or indirectly by a one electron carrier via 0, radicals. This paper tries to indentify a
free radical precursor of mitochondrial H202, which might provide insight into the …
antimycin and rotenone inhibition has been shown to produce considerable amounts of
H202 under certain conditions [l-4]. Since this part of the respiratory chain switches from two
electron transfer to one electron transfer H202 may be formed either directly by a two
electron or indirectly by a one electron carrier via 0, radicals. This paper tries to indentify a
free radical precursor of mitochondrial H202, which might provide insight into the …
A component of the mitochondrial respiratory chain located between the sites of the antimycin and rotenone inhibition has been shown to produce considerable amounts of H202 under certain conditions [l-4]. Since this part of the respiratory chain switches from two electron transfer to one electron transfer H202 may be formed either directly by a two electron or indirectly by a one electron carrier via 0, radicals. This paper tries to indentify a free radical precursor of mitochondrial H202, which might provide insight into the stoichiometry of the primary process. The question of a free radical formation in mitochondria may also be relevant to physiopathology, since eg 0; and one product of its spontaneous dismutation, singlet oxygen, OS, are considered to be more toxic than H202 itself [S, 61. In addition, a continuous generation of 0, radicals by the respiratory chain would disclose a physiological need for the presence of superoxide dismutase (SOD) in the mitochondrial matrix recently discovered by Weisiger and Fridovich [7].
With the aid of bovine blood SOD as an indicator enzyme, we were able to demonstrate that the superoxide radical, at least under some conditions, is a precursor of H202 generated by submitochondrial particles (SMP). Some observations, however, revealed an alternative pathway of mitochondrial H20, formation apparently involving an oxygen species distinct from 0,.
Wiley Online Library