According to the induced-fit model of enzyme action, substrate binding __________.

Correct option is A

The correct answer is (A) induces a conformational change that optimises the active site for catalysis

Explanation:

• The induced-fit model of enzyme action suggests that when the substrate binds to the enzyme's active site, it causes a conformational change in the enzyme's structure. This change optimizes the enzyme’s active site for catalysis, ensuring that the enzyme can efficiently convert the substrate into the product.
• Unlike the lock and key model, which assumes the enzyme and substrate fit together perfectly from the start, the induced-fit model emphasizes that the binding of the substrate elicits a change in the enzyme's shape, making the active site more suited for the catalytic process.

Information Booster:

• The induced-fit model explains how enzymes can accommodate a wide variety of substrates, enhancing their specificity and efficiency.
• The conformational change is typically reversible, allowing the enzyme to return to its original shape after the reaction and release the product.

Additional Knowledge:

(B) Inhibits the enzyme by permanently altering its structure

• This describes the effect of some irreversible inhibitors, not the induced-fit model, which involves reversible conformational changes for catalysis.

(C) Occurs without any change to the enzyme’s active site

• This statement contradicts the concept of the induced-fit model, where the substrate binding does induce a change in the enzyme's structure.

(D) Leads to immediate release of the substrate without transformation

• This statement is incorrect because, in the induced-fit model, the substrate undergoes transformation (catalysis) rather than being released immediately unchanged.