Page 194 - The Manga Guide to Biochemistry

The Michaelis-Menten equation
and the Michaelis constant

In 1913, two biochemists, Leonor
Michaelis and Maud Menten, proposed
a basic equation that represents the
relationship between the reaction rate

and the substrate concentration.

Named after these two scientists,
the equation is called the
Michaelis-Menten equation.

Ohhh...I think I’m Calm down,
getting a migraine. Kumi.

: Reaction rate Yeow
: Substrate concentration
before enzyme is added

Now comes the important part!
In deriving this complex equation,

Michaelis defined a numeric value called

the Michaelis constant (Km ), which is the
substrate concentration when the initial

rate* of the reaction is half of Vmax.

Reaction rate (V) IM P O RTA NT!

180 Chapter 4 Substrate
concentration (S)

* The initial rate is the rate at the beginning of the
reaction, when the substrate concentration and
reaction speed are still linearly related.