Interaction between ubiquinone and ATPase in mitochondrial membranes.


The extraction of ubiquinone from mitochondrial membranes produces alterations of ATPase activity including a reversible loss of oligomycin sensitivity which is restored by long-chain Q-homologs, Short-chain ubiquinones like Q3 produce a loss of oligomycin and dicyclohexyl carbodiimide (DCCD) sensitivity in submitochondrial particles. The effect shows uncompetitive or noncompetitive Kinetics with respect to oligomycin or DCCD respectively. Long-chain ubiquinones have a competitive effect with Q3, thus restoring oligomycin sensitivity; they behave, however, in about the same way as Q3 in lowering the DCCD sensitivity in submitochondrial particles. On the basis of these observations we suggest that ubiquinone may be a physiological modulator of ATPase activity in the mitochondrial membrane.

Cite this paper

@article{Esposti1981InteractionBU, title={Interaction between ubiquinone and ATPase in mitochondrial membranes.}, author={Mirko Degli Esposti and Enrico Bertoli and Giovanna Parenti-Castelli and Giorgio Lenaz}, journal={Journal of bioenergetics and biomembranes}, year={1981}, volume={13 1-2}, pages={37-50} }