What Are Enzymes

• Enzymes

  Catalysts made by living organisms that speed up chemical reactions
• Enzymes

  • They are large proteins made up of long chains of amino acids
  • They can fold into different shapes, each shape catalyzing a particular chemical reaction
• How enzymes work

  1. Enzyme has an active site with a unique shape

  2. Substrate fits into active site

  3. Enzyme speeds up the chemical reaction
• Substrate


  Reactant in a chemical reaction
• Products


  Smaller pieces that a substrate is broken into
• Enzymes speed up chemical reactions without being consumed or permanently altered
• Lock and key model


  Original model where substrate had to fit perfectly into active site
• Induced fit model


  More realistic model where enzyme changes shape slightly to better fit the substrate
• The active site of an enzyme is complementary to the substrate
• The induced fit model is like putting your hand into a rubber glove - the glove molds to your hand