A simplified model of a reaction with and without an enzyme.

<p>Substrate B is yields products C and D with a release of free energy ER. Although the overall reaction is thermodynamically favorable, there is an energy barrier (the activation energy [Ea]) that decreases the rate of the reaction (k). The enzyme, through a key-lock geometric binding with the substrate, has a net effect of reducing the Ea and accelerating the reaction. As described in the text, the information content of the enzyme is expressed geometrically by the formation of a shape within the protein that is precisely complementary to the shape of the substrate. The information is, thus, converted to energy by reducing Ea (ΔEa).