Biochemistry 4th Edition by Christopher Mathews,Kensal van Holde, Dean Appling, Spencer Anthony Cahill

Exercise 14

Note that some of these problems refer to information presented in the Tools of Biochemistry 5A-D.
Sickle cell disease is caused by a so-called "point mutation" in the human -globin gene. A point mutation is the result of a single base substitution in the DNA encoding a gene. The sickle cell mutation results in substitution of Val for Glu at position 6 in the -globin protein.
(a) Using the information in Figure 5.18 explain how a point mutation could change a codon for Glu to a codon for Val.
(b) Do you expect the pI for the sickle cell -globin to be higher or lower than the pI for wild-type -globin Explain.