Structure of proteins

• There are 20 types of amino acids
• What are the four components attached to the central carbon of an amino acid?

  • Amino group
  • carboxyl group
  • R group (side chain)
  • a hydrogen atom
• What type of bond links amino acids together to form proteins?

  Peptide bonds
• What is the primary structure of a protein?

  The sequence of amino acids in a polypeptide chain
• What is the secondary structure of a protein?

  The formation of alpha helices and beta pleated sheets due to hydrogen bonding within the backbone
• What is the tertiary structure of a protein?

  The 3D folding of the polypeptide chain due to interactions between R groups
• What types of interactions stabilize the tertiary structure of proteins?

  • Hydrogen bonds
  • ionic bonds
  • disulfide bridges
  • hydrophillic hydrophobic interactions
• What is the quaternary structure of a protein?

  The arrangement and interaction of multiple polypeptide chains in a protein complex
• What role do disulfide bridges play in protein structure?

  They help stabilize the tertiary structure by forming covalent links between cysteine residues
• Why is the sequence of amino acids important in the primary structure of proteins?

  It determines the protein's final 3D shape and function
• What causes the formation of alpha helices and beta pleated sheets in the secondary structure of proteins?

  Hydrogen bonding between the carbonyl oxygen of one amino acid and the amino hydrogen of another
• How do hydrophobic interactions influence protein folding?

  Hydrophobic side chains tend to cluster in the interior of the protein, away from water, helping to stabilize the protein’s structure