Question

If a Lineweaver-Burk plot was made for an enzyme-catalyzed reaction, both with and without a noncompetitive inhibitor present, what difference would be seen?

a) Parallel lines
b) Lines converging at the x-axis
c) Lines converging at the y-axis
d) No difference in slope

Answer 1

In a Lineweaver-Burk plot, if a noncompetitive inhibitor is present, the lines would converge at the y-axis, with the same slope but different y-intercepts.

Step-by-step explanation:

A Lineweaver-Burk plot is a graphical representation of enzyme kinetics. When a noncompetitive inhibitor is present, the lines on the Lineweaver-Burk plot would converge at the y-axis. This means that the slope of both lines would be the same, but the y-intercept of the line with the inhibitor would be higher than the line without the inhibitor.

For example, in a Lineweaver-Burk plot without an inhibitor, the lines may have different slopes but would intersect at the y-axis. However, in the presence of a noncompetitive inhibitor, both lines would have the same slope but different y-intercepts. This is because the inhibitor affects the maximum reaction rate (Vmax) without changing the affinity of the enzyme for the substrate (Km).