Solution to Exercise 7-2-8
- Page ID
- 43263
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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.