Enzymes

• Enzyme-substrate complex is formed when the substrate binds to an active site on the enzyme.
• The shape of the active site matches that of the substrate, allowing it to fit snugly into place.
• Once bound, the substrate undergoes chemical changes as the enzyme catalyzes its conversion into products.
• Some enzymes can be inhibited by specific molecules called inhibitors.
• Effect of temperature and substrate concentration
• Optimum pH range
• The importance of enzymes
• Enzymes lower activation energy (Ea) required for reaction to occur.
• Enzymes are biological catalysts that speed up biochemical reactions without being used up or changed themselves.
• Activation energy is the minimum amount of energy needed for a reaction to take place.
• reaction rate is the rate of a reaction in a given amount of time or in an equation, 1 over the time
• Substrate


  The substances enzymes act upon

  
• Active Site


  Specific part of an enzyme where a substrate fits

  
• Lock-and-Key Model


  Enzymes and substrates fit together based on their specific shapes like a key fits a lock

  
• pH, Temperature & Concentration


  Three factors that affect enzyme activity
• Acid


  pH between 0-7

  
• Base


  pH between 7-14

  
• Neutral


  pH of 7

  
• Optimal temperature


  Temperature at which an enzyme works the best

  
• Denature


  Change in shape of an enzyme due to extremes in temperature or pH, causes the enzyme to stop functioning
• Protein


  Type of biomolecule an enzyme is
• Names of Enzymes

  Based on their substrates, ends in "-ase" EX: lipid-lipase, protein-protease, lactose-lactase
• Remains Unchanged


  Characteristics of an enzyme after catalyzing a chemical reaction

  
• Concentration


  How much of a substance is present

  
• Optimal pH


  pH at which an enzyme works best

  
• Inhibitor


  A substance that slows down or stops a chemical reaction

  
• Usually ends in -ose

  Substrates
• Usually ends in -ase

  Enzymes