enzymes

• how do enzymes work -

  lower the activation energy of the reaction so it takes less time
• two models -

  lock and key, induced fit
• lock and key model -

  substrate complementary to AS so binds and then splits
• induced fit model -

  substrate and AS not complementary so both change slightly to fit

  bind and then splits
• effect of temperature -

  rate increases until the optimum temperature

  until too hot and then enzyme denatures
• effect of pH -

  increases until optimum

  until too high and then enzyme denatures
• effect of substrate concentration -

  increases proportionally

  until not enough AS and enzyme concentrati9on becomes a limiting factor
• effect of enzyme concentration -

  increases proportionally

  until no more substrates to fill the enzyme so substrate concentration becomes a limiting factor
• two types of inhibitors -

  competitive and non competitive
• competitive inhibition -

  binds to the AS

  as concentration increases, rate decreases
• non competitive inhibition -

  binds elsewhere and changes the shape of the active site

  substrate no longer complementary

  as concentration increases, rate decreases