Lecture 6

Question 1

What is osteogenesis imperfecta?

Answer 1

Collagen contains glycine as every third amino acid in its protein structure. Due to a mutation that causes glycine to be switched with another amino acid, bones break easily.

Question 2

What are transmissible spongeform encephalopathies (TSE)?

Answer 2

A nervous system disorder caused by a prion protein inducing misfolding of normal proteins.

Question 3

Why do proteins have a fairly rigid structure?

Answer 3

A partial double bond can occur among peptide bonds do to resonance from each carbonyl group.

Question 4

What ultimately causes neurodegeneration in protein misfolding diseases?

Answer 4

A prion protein changes from the constitutive (alpha helix) form to the scrapie (beta sheet) form, causing the protein to become insoluble.

Question 5

Is the interior of a protein hydrophilic or hydrophobic?

Answer 5

Hydrophobic

Question 6

What proteins facilitate folding?

Answer 6

Protein disulfide isomerases, Peptidyl prolyl isomerases, & chaperone proteins

Question 7

What does a Protein disulfide isomerase do?

Answer 7

Shuffles disulfide crosslink combinations

Question 8

What does a Peptidyl prolyl isomerase do?

Answer 8

Interconverts cis and trans forms of proline