At pH 7, approximately what charge would be on your peptide? Explain your answer. (2 marks)

The charge on a peptide at pH 7 would depend on the number and type of amino acids it contains.

Amino acids have both a carboxylic acid group (-COOH) and an amino group (-NH2). At pH 7, the carboxylic acid group would be deprotonated (lose a hydrogen ion) and carry a negative charge, while the amino group would be protonated (gain a hydrogen ion) and carry a positive charge.

However, the overall charge of the peptide would also be influenced by the side chains of the amino acids. Some side chains can carry a positive or negative charge, depending on their pKa and the pH of the solution.

For example, the side chains of the amino acids lysine and arginine carry a positive charge at pH 7, while the side chains of aspartic acid and glutamic acid carry a negative charge.

Therefore, to determine the overall charge of the peptide at pH 7, you would need to know the sequence of amino acids and calculate the total number of positively and negatively charged groups.

If the peptide has more positively charged groups, it would have a net positive charge. If it has more negatively charged groups, it would have a net negative charge. If it has an equal number of positively and negatively charged groups, it would be neutral.