Factors affecting enzyme activity

• Temperature:

  • Rate of reaction increases until optimum temp
  • More KE, more collisions, more complexes form
  • Above optimum temp, rate of reaction decreases, enzyme denatures
• pH:

  • Rate of reaction increases until optimum pH
  • Above optimum pH, enzyme denatures
  • Hydrogen + ionic bonds that maintain tertiary structure break
  • Enzyme changes shape
  • Enzyme-substrate complex cant form
• Substrate conc:

  • As it increases, rate of reaction increases
  • More enzyme-substrate complexes form, because more collisions
  • Levels off, no more enzyme-substrate complexes form, active sites are occupied
  • Enzyme conc becomes limiting factor
• Enzyme conc:

  • As it increases, rate of reaction also increases
  • More active sites for substrates to bind to
  • Levels off because there are more active sites than substrates
  • Substrate conc becomes the limiting factor