Final answer:
A non-competitive inhibitor affects the maximum velocity (Vmax) of an enzyme on a Lineweaver-Burk graph, resulting in a steeper slope and indicating a reduced reaction rate at saturation levels of substrate.
Step-by-step explanation:
On a Lineweaver-Burk graph, the presence of a non-competitive inhibitor will change the slope of the line without affecting the x-intercept, representing the enzyme's Michaelis constant (Km). Unlike competitive inhibitors that compete with the substrate for the active site, non-competitive inhibitors bind to a separate site on the enzyme. This binding does not depend on the substrate concentration and therefore, adding more substrate won't mitigate the inhibition effect. The non-competitive inhibitor affects the enzyme's Vmax (maximum velocity), reducing the rate at which the enzyme can catalyze the reaction at saturation levels of substrate. This results in a Lineweaver-Burk plot with a steeper slope compared to that without the inhibitor, as it indicates a lower Vmax.