Factors affecting enzymes

• What is the effect of temperature on enzyme controlled reaction?

  • At low temperatures, there is not enough kinetic energy for successful collisions between the enzyme and substrate.
  • At too high a temperature, enzymes denature, the active site changes shape and enzyme-substrate complexes cannot form
• What is the effect of pH on enzyme-controlled reaction?

  • Too high or too low a pH will interfere with the charges in the amino acids in the active site.
  • This breaks the ionic and hydrogen bonds holding the tertiary structure in place
  • therefore the active site changes shape and the enzyme denatures
  • Different enzymes have a different optimal pH
• What is the effect of substrate concentration on enzyme-controlled reaction?

  • At low substrate concentrations, there will be fewer collisions between the enzyme and substrate.
  • At high substrate concentrations, the rate plateaus because all the enzyme active sites are saturated
• What is the effect of enzyme concentration on enzyme-controlled reaction?

  • At low enzyme concentrations, there will be fewer collisions between the enzyme and substrate.
  • At high enzyme concentrations, the rate plateaus
  • because there are more enzymes than the substrate, so many empty active sites.