Proteins 1

  1. What are the biological roles of proteins?
    • Structure - eg collagen, keratin
    • Transport - membrane transporters eg albumin
    • Enzymes - catalyse biological reactions
    • Motility - eg myosin in muscle
    • Immune system - immunoglobulins
    • Metabolic regulation - hormones eg insulin, glucagon
  2. There are two forms of amino acids (enantiomers).  What are they?
    D-amino acids and L-amino acids
  3. Which form of amino acids are incorporated into proteins/polypeptides and why?
    L-amino acids as the enzymes that join amino acids together can only incorporate L-amino acids
  4. What are the different types of amino acid side chains?
    • Hydrophobic and aliphatic - straight chain hydrocarbons
    • Hydrophobic and aromatic - contain a benzene ring
    • Hydrophilic and charged - contain charged particles 
    • Hydrophilic and neutral - overall they have no charge
  5. What is the amino acid found at the beginning of most protein sequences?
  6. What amino acid is important in disulphide bond formation?
  7. Proteins are always formed from the … terminal to the … terminal?
    N to the C terminal
  8. What interaction occurs in the 1y structure of proteins?
    Peptide bonds between amino acids
  9. What interaction occurs in the 2y structure of proteins?
    Hydrogen bonding
  10. What are the two types of 2y protein structure?
    Alpha helix and beta sheets
  11. What interaction occurs in the 3y structure of proteins?
    Side chain (R group) interactions
  12. What are the different types of side chain interactions?
    • Hydrogen bonding
    • Electrostatic interactions between charged groups
    • Hydrophobic interactions
    • Van der Waals' forces
    • Disulphide bonds
  13. What interaction occurs in the 4y structure of proteins?
    Interactions between subunits
Card Set
Proteins 1
Module 2 - Week 1 - Proteins 1