Question

V_max is best defined as:

• A. The rate of the enzymatic reaction at which any further increase in the substrate concentration will have no effect on the velocity of the reaction
• B. The fastest possible rate at which the enzyme forms a product.
• C. The velocity of the reaction at the point where the enzymes are saturated.
• D. The substrate concentration at maximum enzyme activity

Answer 1

Answer: (A), (B), (C)

The velocity of the reaction at the point where the enzymes are saturated.

V_max or maximum velocity of an enzymatic reaction can be defined as the rate of the reaction at which the enzyme shows highest turnover. Increasing the substrate concentration indefinitely does not increase the rate of an enzyme-catalyzed reaction beyond a certain point. This point is reached when there are enough substrate molecules to completely fill (saturate) the enzyme's active sites. Active site is the substrate binding - reaction site of the enzyme. The maximal velocity, or V_max, is the rate of the reaction under these conditions. V_max reflects how fast the enzyme can catalyze the reaction.


V_max is not the substrate concentration.