Take Home Quiz 3

1.  When measuring horse radish peroxidase, you found that a purified preparation has a specific activity
of 10 mmolar/sec/mg protein.  Suppose you added to an assay a competitive inhibitor that would not
produce a colored product.  What should happen to the specific activity if the inhibitor bound the enzyme with
the same affinity as O-diansidine?   (3 points).

















2.  Answer question 1 above if the inhibitor binding constant was 10 times less than the Km for substrate.
(3 points).















3.  What is the difference between the solvents used to run TLC's of polar and non-polar lipids?  Why is
this so?  (4 points).


















4.   Which solvent mixture is more nonpolar?

a. CHCl3:CH3OH:CH3COOH (70:30:1)

b. CHCl3:CH3OH:CH3COOH (30:70:1)



5. Which acid would travel the farthest on a thin layer

chromatogram developed in CHCl3:CH3OH:CH3COOH (70:30:1)?

a. valine

b. serine

c. stearic acid

d. DNP-aspartic acid