Generation of superoxide anion by the NADH dehydrogenase of bovine heart mitochondria

In the present paper we offer more evidence of the NADH dehydrogenase-supported production of 02-

J F Turrens

2015

Scholarcy highlights

  • Submitochondrial particles from bovine heart in which NADH dehydrogenase is reduced by either addition of NADH and rotenone or by reversed electron transfer generate 0.9 + 0.1 nmol of 02-/min per mg of protein at pH 7.4 and at 300C
  • In the present paper we offer more evidence of the NADH dehydrogenase-supported production of 02
  • Addition of NADH to submitochondrial particles supplemented with adrenaline and respiratory inhibitors such as rotenone, antimycin, and cyanide brought about adrenochrome formation at rates of 0.4-1.8 nmol/min per mg of protein over the first 4-5 min after the reaction started [Fig. 1, traces
  • A similar biphasic effect of rotenone was described in pigeon heart mitochondria in the presence of antimycin, when assayed for H202 generation supported by NAD-linked substrates
  • The antimycin-supplemented mitochondrial membranes with NADH or succinate as substrate showed a second maximum at pH 8.6-8.8, which seems close to the optimal pH values previously reported, about 8.0-8.2
  • Production of 02- by the NADH dehydrogenase of the respiratory chain was reported by Rich & Bonner in potato mitochondria, and by Takeshige & Minakami in bovine heart mitochondria
  • Cyanide distinguishes between the two 02- production sites: it inhibits the ubiquinone-cytochrome b site but does not affect NADH dehydrogenase, as pointed out by Rich & Bonner

Need more features? Save interactive summary cards to your Scholarcy Library.