Final answer:
A noncompetitive inhibitor does not prevent the enzyme from binding its substrate. Increasing the substrate concentration will not reverse the inhibitory effect of a noncompetitive inhibitor. Noncompetitive inhibitors do not affect the enzyme Vmax.
Step-by-step explanation:
A noncompetitive inhibitor can bind to either the free enzyme or the enzyme-substrate complex because its binding site on the enzyme is distinct from the active site. Binding of this kind of inhibitor alters the three-dimensional conformation of the enzyme, changing the configuration of the active site with one of two results. Either the enzyme-substrate complex does not form at its normal rate, or, once formed, it does not yield products at the normal rate.
Increasing the substrate concentration in the presence of a noncompetitive inhibitor will not reverse the inhibitory effect.
Noncompetitive inhibitors do not affect the enzyme Vmax. The inhibitor binds to a different site on the enzyme, causing a structural change that reduces the overall enzyme activity. Increasing the substrate concentration will not overcome this inhibition because the inhibitor is not competing with the substrate for the active site.