1. Factors affecting the rate of enzyme reaction
   1. Temperature
      1. Q10 = 2
      2. Q10 = x + 10 / x
      3. Optimum temperature = 40
      4. Inactive at low temperature, denature at high temperature
   2. pH
      1. Each kind of enzyme have its own optimum temperature
      2. pH change --> ionic change on amino acid changes --> bond breaking --> Shape of active site change --> denature
   3. Enzyme concentration
      1. Will limited by substrate concentration after certain extent
   4. Substrate concentration
      1. Will limited by enzyme concentration after certain extent
2. Inhibition
   1. Reversible inhibitors
      1. Competitive
         1. Have similar shape to substrate
         2. compete with substrate for active site
         3. Can be solved by increasing substrate concentration
      2. Non-competitive
         1. Have different shape with substrate
         2. Bind to inhibitor site, but loosely
         3. alter the structure of active site
         4. Reaction hindered
            1. Depend on inhibitor concentration and binding affinity of enzyme
         5. No solution
   2. Irreversible inhibitors
      1. Bind irreversibly with enzyme
   3. End-product inhibition
      1. Metabolism proceed in small steps
         1. Prevent vigorous reactions
         2. Effective use of energy
         3. intermediates are useful to other metabolic pathways
   4. Negative feedback inhibition
      1. End-product will bind with enzyme to regulate the yield of product, as to adjust the metabolic rate to suit the demand
3. Applications
   1. Washing powders
   2. Meat tenderizers
   3. Fructose Syrups
   4. Analytical reagents
4. Cofactors
   1. Non-protein components of enzyme molecules
      1. Organic compounds
         1. Firmly bound (prosthetic groups)
            1. e.g. FAD
         2. Loosely bound (coenzymes)
            1. Atom carriers e.g. NADP
      2. Inorganic compounds (activators)
         1. e.g. Metal ions
5. Mechanism
   1. Active site
      1. Have same/similar shape with substrate
         1. Forming enzyme-substrate complex upon binding
   2. Lock and key hypothesis
      1. Highly specific
   3. Induced-fit hypothesis
      1. Substrate induce change of shape of enzyme upon binding
         1. Dynamic interactions
6. Properties
   1. Speed up chemical reactions
      1. So as called catalyst
   2. Only small amount is needed
   3. Reusable since they remain unchanged
   4. Nature of products are not affected
   5. Catalyzing both forward and backward reactions equally
   6. They are globular proteins
      1. Highly specific
      2. Affect or denature by extreme conditions (pH, temperature,etc)
7. Use in metabolism
   1. Since they lowered activation energy of reactions