Question

The isoelectric point of Ala-Lys-Asp-Arg-Val-Ile-Glu is

a) Below 7
b) Exactly 7
c) Above 7
d) Cannot be determined

Answer 1

The isoelectric point of the sequence Ala-Lys-Asp-Arg-Val-Ile-Glu lies above 7. The option (C) is correct.

Step-by-step explanation:

The isoelectric point (pl) is the pH at which an amino acid carries no net charge and is neutral overall. For the sequence Ala-Lys-Asp-Arg-Val-Ile-Glu, we can determine its isoelectric point by examining the charges of each amino acid.

Alanine (Ala) and isoleucine (Ile) have nonpolar side chains and are neutral at pH 6. Lysine (Lys) and arginine (Arg) have positively charged side chains at neutral pH, so they are positively charged at a pH below their isoelectric point, which is above 7. Aspartic acid (Asp) and glutamic acid (Glu) have negatively charged side chains at neutral pH, so they are negatively charged at a pH above their isoelectric point, which is below 7. Therefore, option (C) is correct.