Question

Kinetic constants for inhibition studies on enzymes are described below. For each part a-h, determine if the numerical values for the constants are identical or different (increased or decreased).

a) Km values in the absence and presence of a competitive inhibitor
b) Vmax values in the absence and presence of a competitive inhibitor
c) Km values in the absence and presence of a noncompetitive inhibitor
d) Vmax values in the absence and presence of a noncompetitive inhibitor
e) Km values in the absence and presence of an uncompetitive inhibitor
f) Vmax values in the absence and presence of an uncompetitive inhibitor
g) Slope in the presence of noncompetitive inhibitor in a Lineweaver-Burk plot
h) How the y-intercept would will be affected by the presence of noncompetitive inhibitor

Answer 1

a)
Km value is increased in presence of competitive inhibitor
b)
Vmax value is identical
c)
km value is uneffected
d)
vmax value is decreased in presence of noncompetitive inhibitor
e)
Km value is decreased in presence of uncompetitive inhibitor
f)
Vmax value is decreased in presence of uncompetitive inhibitor
g)
slope increases
h)
y intercept increases