Suppose you increased the pH of the biotin solution from 7.0 to 9.0 -what would happen to the ionizable group on a molecule of biotin as the pH shifted from 7.0 to 9.0?

2. | Calculate the overall charge (pH 7) on the following three polypeptides and answer the questions below. Assume the following pKa values: N-terminal -NH3®, 7.0; all -COOH groups, 4.0; Arg, 12.5; Cys, 8.4; His, 6.0; Lys, 10.0; Tyr, 10.0. (A) Ser-Tyr-Ser-Met-Glu-His-Phe-Arg-Trp-Gly-Lys-Pro-Val-Gly-Lys-Lys-Arg-Arg-Pro-Val-Lys-Val-Tyr-Pro-Asp-Ala -Gly- Glu-Asp-Gln- Ser-Ala-Glu-Ala-Phe-Pro-Leu-Arg-Glu-Phe (B) Ser-Tyr-Ser-Met-Glu–His-Phe-Arg–Trp–Gly-Ala-Pro-Val-Gly-Glu-Glu-Cys-Asp-Pro-Val-Glu–Val-Tyr-Pro-Asp- Ala-Gly-Glu-Asp-Gln-Ser-Ala-Glu-Ala-Phe-Pro-Leu-Glu-Phe-Cys-Ser-Tyr-Ser-Met-Glu-His-Phe-Asp-Trp-Gly- Asp-Pro-Val-Gly-Pro-Asp-Ala-Gly-Asp-Gln-Pro-Val-Gly-Glu-Glu-Cys-Asp-Pro-Val-Glu-Val-Tyr-Pro-Asp-Ala | (C) Gly-Ser-Val-Arg-Asp-Pro-Val-Lys-Glu–Val-Tyr-Pro-Asp- Lys-Ala-Gly-Arg-Glu-Ser-Arg-Ala (a) Which of the three peptides would elute first from a gel filtration column? (b) Which of the three peptides would migrate the fastest on SDS-PAGE (c) Which of the three peptides could be…

3c) Suppose you had a solution of histidine molecules and you adjusted the pH of that solution to pH 5.0. What would the net charge on each molecule of histidine in that solution be?

Can you please explain how to solve this problem?