Final answer:
An enzyme's KM value being close to the normal substrate concentration ensures efficient enzyme operation and responsiveness to substrate availability, maintaining metabolic efficiency and resource use in the cell.
Step-by-step explanation:
It is considered a biochemical advantage for an enzyme to have a KM approximately equal to the substrate concentration as it allows the enzyme to operate efficiently in the cellular environment. KM is indicative of the substrate concentration at which the enzyme achieves half its maximum reaction rate (1/2Vmax). Thus, when the KM is close to the concentration of substrate normally available (in vivo conditions), the enzyme can effectively respond to fluctuations in substrate levels, operating near its optimum without being wasteful or ineffective
An enzyme with a KM approximating the normal substrate concentration demonstrates responsiveness in changing conditions, as it allows the enzyme to be more sensitive to changes in substrate levels. This ensures that the enzyme can rapidly adjust its activity in accordance with substrate availability, enabling the cell to maintain metabolic efficiency and react to both increases and decreases in substrate concentration.
The responsiveness of an enzyme to cellular substrate concentration augments its catalytic ability, as alterations in the availabilty of the substrate can be promptly matched by changes in enzyme activity, thereby ensuring that metabolic pathways are closely regulated and that resources are used judiciously.