The Ninth Sir Hans Krebs Lecture. Compartmentation and communication in living systems. Ligand conduction: a general catalytic principle in chemical, osmotic and chemiosmotic reaction systems.

Chemical reactions, like osmotic reactions, are transport processes when looked at in detail. Chemical catalysis by enzymes or catalytic carriers, and osmotic catalysis by porters, may be conceived as occurring by specific ligand-conduction mechanisms. In chemiosmotic reaction systems, the pathways of specific ligand conduction are spatially orientated through anisotropic enzyme and catalytic carrier complexes in which the reactions of chemical group transfer occur as vectorial diffusion processes of group translocation down gradients of group potential that represent real spatially-directed fields of chemical force. Thus, it is easier to explain biochemistry in terms of transport than it is to explain transport in terms of biochemistry.