Enzyme activity quantifies the rate at which an enzyme catalyzes a specific biochemical reaction. It is typically expressed as the amount of substrate converted per unit time, or the amount of product formed per unit time, under defined conditions, such as temperature, pH, and substrate concentration. For instance, activity can be measured by monitoring the increase in absorbance due to the formation of a colored product using spectrophotometry.
Understanding enzyme activity is crucial in various fields, including diagnostics, drug development, and industrial biotechnology. Accurate measurement provides insights into enzyme kinetics, enabling the optimization of enzymatic reactions and the identification of enzyme inhibitors or activators. Historically, advancements in quantifying enzyme function have significantly contributed to progress in understanding metabolic pathways and developing novel therapies.