Apoptosis and the laws of thermodynamics

The 'chemiosmotic hypothesis', formulated in the 1960s, revolutionized the study of the mitochondrion and made it accessible to thermodynamic analysis. The central aspect of the hypothesis is that the energy from electron transport is transduced into a proton electrochemical gradient (Δp) across the inner membrane, and that protons re-entering the matrix through the F1Fo ATPase force this proton pump to run in reverse to generate ATP. We discuss recent results by Matsuyama et al. (Nature Cell Biology 2, 318–325; 2000) in the light of these chemiosmotic principles