Michaelis constant

K_m = Michaelis constant

K_m = the value of [S] that causes V= ½ V_max *

The units of K_m are M, concentration

K_m indicates the affinity of the enzyme for its substrate and thus the stability of the Enzyme-Substrate Complex.

High K_m demonstrates a low affinity; Low Km demonstrates a high affinity.

Velocity is related to K_m through the Michaelis & Menten equation: v = (V_max [S])/(K_m + [S])

• V_max = maximum rate of reaction achievable for the enzyme under given conditions, only occurs at infinite substrate concentration

[S] = substrate concentration