Oxidative Phosphorylation, Part II

Flashcards covering the mechanisms of NADH shuttles, ATP-ADP transport, ATP yield calculations, and the regulation of oxidative phosphorylation.

Glycerol phosphate shuttle

A mechanism used in muscle cells where electrons from cytoplasmic NADH are transferred to $FADH_2$ and subsequently to $Q$ to form $QH_2$ for entry into the electron-transport chain.

Malate–aspartate shuttle

A shuttle consisting of two membrane transporters and four enzymes used in the heart and liver to generate mitochondrial NADH from electrons provided by cytoplasmic NADH.

ATP–ADP translocase

A transporter powered by the proton-motive force that enables the coupled exchange of cytoplasmic ADP for mitochondrial ATP.

ATP synthasome

A large complex formed by the association of the ATP–ADP translocase, the phosphate carrier, and the ATP synthase.

Complete combustion of glucose

A metabolic process yielding about $30$ molecules of ATP, where $26$ are formed in oxidative phosphorylation and $4$ are formed in glycolysis.

Fermentation

A metabolic process that generates only $2$ molecules of ATP per glucose molecule.

Acceptor control

Also known as respiratory control, it is the regulation of the rate of oxidative phosphorylation based on the availability of ADP.

Proton-motive force equation

The mathematical model used to quantify energy associated with ion flow, represented as $\Delta G = RT \ln(Ratio) + ZF\Delta\psi$.

Eversion

The mechanism or structural change used by the Mitochondrial ATP-ADP Translocase to facilitate the exchange of ATP and ADP across the inner mitochondrial membrane.

Energy charge

The physiological status that governs the control of metabolism, exemplified by the regulation of oxidative phosphorylation via acceptor control.