Hint For this exercise total number of amino acids number o

[Hint: For this exercise, total number of amino acids = (number of nonpolar amino acids) + (number of polar and charged amino acids).]

1) approximately the same polar and nonpolar amino acids

2) predominantly nonpolar

3) predominantly polar

A)     Based on this table and the structures of the amino acids (Figure 5.14 in your textbook), how many polar amino acids and charged amino acids are present in this molecule?
B)     How many nonpolar amino acids are present in this molecule?
C)     What is the maximum number of disulfide bonds this protein can have?
D)     This protein has 147 amino acids. Based on the amino acid composition, this protein is (Pick 1, 2 or 3) 1) approximately the same polar and nonpolar amino acids 2) predominantly nonpolar 3) predominantly polar

Number in Amino acid Number in Amino acid hemoglobin hemo obin 17 11 Alanine Leucine Arginine Lysine 12 Methionine Asparagine Asparatic acid Phenylalanine Cysteine Proline Glutamic acid Serine 11 8 Threonine Glutamine 10 Glycine 13 Tryptophan Histidine Tyrosine Valine Isoleucine 13

Solution

A)     how many polar amino acids and charged amino acids are present in this molecule?

Polar amino acids: Total 39

Serine: 11

Threonine: 10

Cysteine: 1

Proline: 4

Asparagine: 5

Glutamine: 8

Charged amino acids: Total 34

Lysine: 12

Arginine: 3

Histidine:7

Aspartate: 8

Glutamate: 4

  

B)     How many nonpolar amino acids are present in this molecule?    

Non polar amino acids: Total 74

Glycine: 13

Alanine: 11

Leucine: 17

Isoleucine: 4

Methionine: 3

Valine: 13

Phenylalanine: 8

Tyrosine: 2

Tryptophan:3  

C)     What is the maximum number of disulfide bonds this protein can have?      

Zero, since there is only one cysteine is present it cannot make disulphide bond (we need two to make a disulfide bond)

D)     This protein has 147 amino acids. Based on the amino acid composition, this protein is   (Pick 1, 2 or 3)

           2) predominantly nonpolar