Week 7 Catalytic strategies

• Oxidoreductases:

  • oxidation = loss of electrons
  • reduction = gain of electrons
  • biological oxidations often involve dehyrogenation

  
• Transferases:

  • group transfer

  
• Hydrolases:

  • bonds are cleaved by the addition of water

  
• Lyases:

  • additional or removal of groups

  
• Isomerases:

  • intramolecular group transfer

  
• Ligases:

  • ligation reactions form bonds by using the free energy from ATP cleavages

  
• Enxymes and rate of reaction:

  • enzymes increase the rate of reaction by lowering activation energy
  • use alternative pathway with lower activation energy

  A) uncatalysed

  B) catalysed

  
• Catalytic modes:

  • common catalytic strategies include
  • covalent catalysis
  • acid base catalysis
  • cataliysis by approximation
  • metal ion catalysis