Michaelis-Menten

• • The Michaelis-Menten model is used to investigate the kinetics of enzyme catalysed reactions (enzyme kinetics is an area in biochemistry that studies how different variables affect reaction rates)
• Vmax


  Maximum rate of reaction at saturating substrate concentrations
• Km


  Substrate concentration at ½Vmax (also known as the Michaelis-Menten constant)
• Michaelis-Menten constant


  Substrate concentration at which the enzyme works at half its maximum rate
• At the Michaelis-Menten constant, half of the active sites of the enzyme are occupied by substrate molecules
• The higher the affinity of the enzyme for the substrate


  The lower the substrate concentration needed for half the active sites to be occupied
• The Michaelis-Menten constant is a measure of the affinity of an enzyme for its substrate
• • There is an inverse relationship between the Km and the affinity of an enzyme for its substrate
  • An enzyme with a high Km has a low affinity for its substrate and an enzyme with a low Km has a high affinity for its substrate