Molecular ratchets

They force chemical reactions to run backwards, driving them energetically uphill. Molecular ratchets trap unstable molecules, spin molecular motors, and even generate electricity from light.

The chemical reactions we perform in the lab, whether they are under thermodynamic or kinetic control, form thermodynamically stable products. Nature, on the other hand, often operates away from thermodynamic equilibrium and carries out endergonic reactions. To perform endergonic reactions, nature pairs them with exergonic processes, leveraging the free energy released like a fuel. These reaction cycles are called molecular ratchets. They allow nature to develop specific structures and perform functions vital for life. Just like a mechanical ratchet permits movement solely in one direction, a molecular ratchet^1,2) is a chemical reaction cycle, where the components predominantly react in a single direction.

What does such a molecular ratchet look like? Considering the endergonic reaction converting A to B (Figure 1), B is not formed spontaneously. To produce B from A, an alternative reaction pathway driven by exergonic reactions must be

Wissenschaft + ForschungBlickpunkt Synthese