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