THE CHEMIOSMOSIS — a dart

THE CHEMIOSMOSIS a waterwheel for making energy

Mitchell’s heretical idea, now textbook: cells don’t pass energy hand-to-hand as chemicals — they pump protons across a membrane to build a gradient, then let those protons flood back through a molecular turbine, ATP synthase, whose spinning rotor stamps out ATP. A ring of ~10 subunits turns once per 10 protons and makes 3 ATP — about 3.3 protons per ATP. Every breath you take powers this waterwheel.

THE TECHNIQUE proton gradient → rotor → ATP (~3.3 H⁺/ATP)

The demo computes the rotor stoichiometry — protons per revolution and per ATP: live demo

HISTORY & CREDIT Peter Mitchell · 1961

“ATP is made by a chemical intermediate.” — Mitchell showed the intermediate is a proton gradient, not a molecule; heresy in 1961, Nobel by 1978. cited

pump · the electron chain pumps protons out, building an electrochemical gradient.
the turbine · protons flood back through ATP synthase; the c-ring spins — ~10 H⁺ per turn, 3 ATP.
1961 · Peter Mitchell (Nobel 1978); the rotor by Boyer & Walker (Nobel 1997).

A gradient, spun into the currency of life. bioenergetics

RECOMMEND FOR I-13 the stoichiometry, on the compiler

On i-13, a 10-subunit ring gives 10 protons per revolution and 3 ATP — 3.3 H⁺ per ATP:

$ i13 run lf_chemiosmosis.i13 RUN OK · 22 step(s) protons_per_rev = 10 atp_per_rev = 3 h_per_atp_x10 = 33.3 rotary_motor = 1 drives = 1

Recommend as a NULL — a pinned stoichiometry (B39). The proton/ATP ratio is fixed by the ring geometry; the gradient driving it is thermodynamics, not a same-function DOF. NULL — a waterwheel for making energy.