Proton motive force

Definition

Proton motive force (PMF) is the potential energy stored across a membrane due to the difference in proton concentration and electrical charge. It is essential for ATP synthesis during cellular respiration.

5 Must Know Facts For Your Next Test

1. PMF is generated by the electron transport chain during cellular respiration.
2. It drives ATP synthesis by ATP synthase through chemiosmosis.
3. PMF consists of two components: a chemical gradient (ΔpH) and an electrical gradient (Δψ).
4. Disruption of PMF can halt ATP production, affecting cell survival.
5. In bacteria, PMF is also used for transporting nutrients and powering flagella.

Review Questions

• What creates the proton motive force in cellular respiration?
• How does proton motive force contribute to ATP synthesis?
• Name two components that constitute the proton motive force.

Related terms

Electron Transport Chain:

A series of protein complexes that transfer electrons and pump protons to create a proton gradient.

Chemiosmosis:

The process through which ATP synthase uses the energy from a proton gradient to produce ATP.

ATP Synthase:

An enzyme that synthesizes ATP as protons flow through it, driven by the proton motive force.