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Thermodynamic and steady-state-kinetic investigation of the effect of NN'-dicyclohexylcarbodi-imide on H+ translocation by the mitochondrial cytochrome bc1 complex.

ABSTRACT: Steady-state kinetic measurements showed that NN'-dicyclohexylcarbodi-imide decreased the observed H+/2e ratio of H+ transport by mitochondria respiring on succinate, acting mainly at the cytochrome bc1 complex. Thermodynamic assessment of the H+/2e ratio by measuring the force ratio across the bc1 complex showed that the inhibitor did not affect H+ translocation. Possible explanations of this disagreement between methods are examined; we conclude that the inhibitor does not alter the mechanistic stoichiometry of H+ pumping by the bc1 complex.

SUBMITTER: Brand MD

PROVIDER: S-EPMC1144604 | biostudies-other | 1985 Jan

REPOSITORIES: biostudies-other

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Proton translocation by the mitochondrial cytochrome b-c1 complex is inhibited by NN'-dicyclohexylcarbodi-imide.

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