protein structure

• Proteins

  Polymers made up of amino acids
• Amino acids

  Monomers that proteins are made up of
• General structure of amino acids

  Central carbon with 4 different groups: amino group, carboxyl group, R group, hydrogen
• Condensation reaction

  Reaction where two monomers join together, eliminating water, to form a bond
• Peptide bond

  Bond formed when two amino acids join together in a condensation reaction
• Levels of protein structure

  • Primary
  • Secondary
  • Tertiary
  • Quaternary
• Primary structure


  Order of amino acids in a polypeptide chain
• Secondary structure


  • Polypeptide chain gets twisted into alpha helix or bent into beta pleated sheet, held in place by hydrogen bonds
• Tertiary structure


  • Protein gets further folded into unique 3D shape, held in place by ionic bonds, hydrogen bonds, and disulfide bonds
• Quaternary structure


  • Unique 3D shape formed by more than one polypeptide chain
• Denaturation of proteins


  Bonds in tertiary structure (ionic and hydrogen bonds) break, causing protein to lose its unique 3D shape
• Sequence of amino acids determines the 3D shape and function of a protein
• Mutation


  Change in DNA sequence that can lead to a change in amino acid sequence