ENZYMES

ENZYMES

1. Lower Activation Energy

   • Combine with reactants and remain unchanged
   • Alters the rate of a reactions (speeds it up)
   • Induce the transition state
   • Activation energy is a kinetic barrier
   • An initial input of energy (Even for spontaneous reactions)

2. Conditions that effect enzymes

   • Temperature
     • Optimum temperature
       • Past = Denature
   • PH
     • Average optimal at pH 7
       • Changes affect amino acids
       • Secreted enzymes may have higher pH
     • some optimal in basic or acidic

3. Many require a cofactor

   • Inorganic ions or organic nonprotein groups
     • Cofactors: Metallic Ions Coenzymes: organic cofactors ie. vitamins

4. 3 Fundamental Mechanisms

   • Bringing reacting molecules together
   • Exposing the reactant molecule to altered charge environments that promote catalysis
   • Changing the shape of the substrate molecule

5. Catalyst - speeds reaction without partaking

   • Biological Catalysts

6. ENZYME SPECIFICITY

   • 1 kind of substrate (sometimes very similar molecules)
   • Induced-fit hypothesis
     • Intermediate transition state
   • Catalytic cycle