enzymes

• Catalyst


  Substance that speeds up a reaction without being used up
• Activation energy


  The minimum amount of energy required for a reaction to take place
• Active site


  Specific part of an enzyme that substrate binds to
• ES complex


  Molecule formed when Enzyme + Substrate bind
• EP complex


  Molecule formed when enzyme and product are bound
• Catabolism


  Breakdown reaction
• Anabolism


  Buildup reaction
• Enzyme specificity


  • Each enzyme is specific to a particular substrate
• Complementary active site


  Active site is an exact match to the shape of the substrate
• Lock and key


  Enzymes active site and the substrate fit together
• Induced fit


  Enzyme's active site can mould itself around the substrate
• Cofactors


  Non-protein substances that enzymes require to function
• Prosthetic group


  Type of cofactor, e.g. haem in haemoglobin
• Coenzymes


  Not permanently attached cofactors
• Kinetic energy increases with high temperature


  Molecules move faster increasing possibility of collisions
• Optimum


  Factor level at which enzymes work most effectively
• Denatured


  Permanent and irreversible change
• Inhibitors


  Substances that interfere with enzyme action, reducing activity
• Allosteric


  "Second" active site that non-competitive inhibitors bind to
• Enzymes


  Biological catalysts
• Penicillin


  An enzyme that inhibits enzymes that form cell walls in bacteria, causing the cell to burst
• ACE 


  inhibitor used to treat high blood pressure by inhibiting enzymes that constrict blood vessels
• Antiviral drugs


  Inhibit DNA polymerase
• Methods of immobilising enzymes


  • Adsorption
  • Entrapment
  • Encapsulation
  • Cross linkage
• Adsorption


  Enzymes are attached by weak forces to an inert substance e.g. glass matrix
• Entrapment


  Enzymes are trapped within polymers such as alginate beads or microspheres
• Encapsulation


  Enzymes are trapped inside a selectively permeable membrane e.g. nylon
• Cross linkage


  Enzymes are bonded covalently to a matrix, e.g. cellulose, as a consequence of chemical reactions
• Thermostable


  Enzymes that are main stable and effective across a wide range of temperatures
• Biosensor

  Specific enzymes used to detect or monitor a particular molecule
• Serial dilution


  A method of diluting a solution in a stepwise fashion
• Colorimeter


  Apparatus that measures change of light intensity as it passes through a solution
• Turbid


  Cloudiness (can become more or less)
• A1AT


  elastase inhibitor that prevents activity
• ACE


  inhibitor used to treat high blood pressure. Stops enzyme that constricts blood vesssels
• Elastase


  an enzyme released by white blood cells after lung infection