Biomolecules Question 180
Question: The $ pK_4 $ values for the three ionizable groups X, Y and Z of glutamic acid are 4.3, 9.7 and 2.2 respectively $ \underset{X}{\mathop{HO_2C}}-CH_2-\underset{Y}{\mathop{\underset{ _{+}NH_3}{\mathop{\underset{|}{\mathop{C}}}}H}}-\underset{Z}{\mathop{CO_2H}} $ The isoelectric point for the amino acid is:
Options:
A) 7.00
B) 3.25
C) 4.95
D) 5.95
Show Answer
Answer:
Correct Answer: B
Solution:
[b] In acidic medium $ \frac{4.3+2.2}{2}~=3.25 $
BETA
