Essential Biochemistry - Enzymes (Section 1 - No. 35)
The Michaelis constant (Km) is:
Not changed by the presence of non-competitive inhibitor
Equal to 1/2 Vmax
The substrate concentration at 1/2 Vmax
The equilibrium constant for the dissociation of the ES complex
Explanation
Km is defined as the substrate concentration at which the reaction rate is half of its maximum value (Vmax).