There are several scenarios in which Vmax might remain unchanged:
Enzyme Concentration: If the enzyme concentration remains constant, Vmax will also remain unchanged, assuming all other conditions are optimal and constant. Non-competitive Inhibition: In this type of inhibition, an inhibitor binds to an allosteric site rather than the active site, altering the enzyme’s conformation. This does not change Vmax because the enzyme’s turnover number remains the same when the substrate is bound. Allosteric Regulation: Allosteric effectors that do not affect the enzyme's maximum velocity will leave Vmax unchanged.