# Solution to Exercise 7-2-8

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We must consider the protonation state/charge of all ionizable groups on the peptide - including the terminal amino and carboxylic acid groups - at pH 7.

terminal amino: +1

Cys: thiol, 0

Asp: carboxylate, -1

Lys: ammonium, +1

Glu: carboxylate, -1

terminal carboxylate: -1

Net charge is therefore approximately -1.

Solution to Exercise 7-2-8 is shared under a not declared license and was authored, remixed, and/or curated by .

Solution to Exercise 7-2-8 is shared under a not declared license and was authored, remixed, and/or curated by Tim Soderberg.