Academic Integrity: tutoring, explanations, and feedback — we don’t complete graded work or submit on a student’s behalf.

The sequence of amino acids of the protein pectainse is known. Following is a li

ID: 31796 • Letter: T

Question

The sequence of amino acids of the protein pectainse is known. Following is a list of amino acids and the number of each in the pectinase molecule.

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

predominantly polar

predominantly nonpolar

approximately the same polar and nonpolar amino acids

A)     Based on this table and the structures of the amino acids (Figure 5.14 in your textbook), how many polar amino acids plus charged amino acids are present in this molecule?     Answer B)     How many nonpolar amino acids are present in this molecule?     Answer C)     What is the maximum number disulfide bonds this protein can have?     Answer D)     This protein has 367 amino acids. Based on the amino acid composition, this protein is      

predominantly polar

predominantly nonpolar

approximately the same polar and nonpolar amino acids

Explanation / Answer

It has 164 amino acids and its composition and properties are:

Amino acid composition:

A)

Total number of negatively charged residues (Asp + Glu): 14, Total number of positively charged residues (Arg + Lys): 18. Thus, the total charged amino acids are: 32. Total polar amino acids are 137.

b)

The total nonpolar amino acids are: 2

c)

Total number of cysteines 7 and the Predicted number of bonds are 3. Cysteines at the following positions are predicted to form the disulfide bond: 23,63,105,114,149,154.

Predicted disulfide bonds (cysteine pairs) ordered by probability in descending order:

Bond_Index    Cys1_Position Cys2_Position

1                      149                  154

2                      23                    63

3                      105                  114

D)

Based on the amino acid composition this protein is mainly has polar nature.   

Hire Me For All Your Tutoring Needs
Integrity-first tutoring: clear explanations, guidance, and feedback.
Drop an Email at
drjack9650@gmail.com
Chat Now And Get Quote