What effect does a negative ΔG have on a biochemical reaction?

A negative ΔG (Gibbs free energy change) is crucial for understanding the spontaneity of a biochemical reaction. When ΔG is negative, it indicates that the reaction can occur without the input of energy from external sources, making it spontaneous.

In thermodynamic terms, a negative ΔG means that the products of the reaction have a lower free energy than the reactants, suggesting that the reaction can proceed forward under standard conditions. This drives the reaction towards equilibrium favoring the formation of products, which is essential in various metabolic processes.

This concept is foundational for predicting whether a biochemical pathway can occur under physiological conditions, influencing everything from metabolic pathways to enzymatic activity. Thus, the identification of a negative ΔG is a key indicator of spontaneity and thermodynamic favorability in biological systems.