: a constant that is a measure of the kinetics of an enzyme reaction and that is equivalent to the concentration of substrate at which the reaction takes place at one half its maximum rate
Biographical Note for MICHAELIS CONSTANT
Michaelis,Leonor(1875–1949), German-American biochemist. Michaelis made major contributions to both biochemistry and medicine. In 1913 he derived the Michaelis constant, a measure of the affinity of an enzyme for the substance on which it acts.