ABSTRACT
Grand unification ideas enable paradigm shifts and have the potential to establish new scientific fields. Peter Mitchell united membrane biochemistry with the biochemistry of soluble proteins, electrochemistry with biochemistry, mitochondrial with microbiological cytochrome research, respiration with photosynthesis, ion gradients with vectorial chemistry, and electron transfer with active transport of protons, including conversions among electrical, osmotic, and chemical forms of energy. His prescient proposals about integral membrane proteins acting as enzymes or power-generating units were contested before and after his Nobel Prize in 1978, but previously common opinion that biology is based on chemistry alone (bag-of-enzymes biochemistry) was no longer tenable. Coupled electron-proton currents are the physical mechanism for vectorial metabolism of crucial importance for the catalytic efficiency of different enzymes and membrane-embedded bioenergetic complexes. It is impossible to divorce dissipation from currents from the thermodynamic perspective in classical physics, no matter what particles are mainly responsible for these nanocurrents. Mitchell’s concept of microscopic chemiosmotic coupling principle is also prescient, inspirational, and unfortunately neglected. It can be connected to the concept of microscopic dissipative structures.
