Enzyme Activity Assays
Activity assays are performed to observe how the activity (V0) varies with different concentration of LDH. The enzyme Lactate Dehydrogenase (LDH) exists in two different forms. The H form is mainly found in cardiac muscle and it is optimized to catalyze the oxidation of lactate to pyruvate. The M form, found in skeletal muscle, is optimized to catalyze the reduction of pyruvate to lactate and the simultaneous oxidation of NADH to NAD+. This lab involves purifying the M form of LDH. Because NADH(a reactant) absorbs at 340 nm, measuring absorbance at 340 nm over the course of the reaction will allow us to determine the rate of activity(V0) for LDH.
