Michaelis-Menten kinetics

Definition

Michaelis-Menten kinetics in plain English

Enzymes are the body's tiny machines that speed up chemical reactions, and this is the equation that predicts how fast one runs depending on how much raw material (called substrate) is available. The idea: when there's very little substrate, adding more speeds the enzyme up a lot; but as substrate floods in, every enzyme gets busy and the speed levels off at a top speed called V_max — like a checkout line that can only scan groceries so fast no matter how long the line gets. The formula is v = V_max×[S]/(K_m+[S]), where [S] is how much substrate is around. K_m is a handy landmark: it's the exact substrate amount at which the enzyme runs at half its top speed, so a small K_m means the enzyme grabs its substrate eagerly.

Learn these first

• Enzyme
• Kinetics

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