What characterizes non-competitive inhibition of an enzyme?

Non-competitive inhibition is characterized by the inhibitor binding to a site other than the active site of the enzyme, which causes a change in the enzyme's shape. This alteration affects the enzyme's ability to catalyze a reaction, even if the substrate is still able to bind to the active site. In this scenario, the enzyme's functionality is impaired, which results in reduced overall activity regardless of substrate concentration.

This type of inhibition is distinct because it does not compete with the substrate for binding; instead, it can bind to both the enzyme and the enzyme-substrate complex. This means that even if the substrate is present, the non-competitive inhibitor will still hinder the reaction by affecting the enzyme’s activity through its binding. Thus, this shape change is critical for understanding how non-competitive inhibition can regulate enzyme activity without affecting substrate binding directly.