Powerpoint

• Amino acids


  Monomers that make up proteins
• Building Polypeptides

  1. Draw and label an amino acid

  2. Describe the structure of proteins

  3. Explain how two amino acids join to make a dipeptide
• Amino acid

  Variable group is different in different amino acids
• Dipeptides

  1. How dipeptides are formed

  2. How dipeptides are broken down
• Amino acids


  Smaller units that make up proteins
• Forming a peptide bond

  1. Condensation (reaction) / loss of water

  2. Between amine / NH2 and carboxyl / COOH
• Dipeptide of glycine


  • Peptide bond shown correctly
  • Rest of dipeptide structure shown correctly
• Primary structure

  Bonds found in primary structure
• Secondary structure

  • Bonds found in secondary structure
  • Groups these bonds are in-between
  • Difference between alpha-helix and beta-pleated sheet
• Tertiary structure

  • Type of bonds found in tertiary structure
  • Hydrogen Bonds
  • Ionic Bonds
  • Disulfide bridges
  • Groups these bonds and interactions are between
• Quaternary structure

  • Definition of quaternary structure
  • Protein with quaternary structure and a prosthetic group
  • What would happen if amino acid sequence in primary structure changed
• Different sequence of amino acids

  Forms ionic / hydrogen / disulfide bonds in different places
• Quaternary structure


  Two or more polypeptides
• Two enzymes with different amino acid sequences

  Can catalyse the same reaction
• Active sites have similar/identical tertiary structures or identical amino acid sequences
• So both form enzyme-substrate complexes with the same substrate
• Types of proteins

  • Fibrous
  • Globular
• Globular proteins


  • Enzymes
  • Antibodies
• Fibrous protein

  • Collagen