Draw the structure of a tripeptide glutathione with the following amino acid residues: Glu-Cys-Gly. What is the net charge of the tripeptide?
At physiological pH?
- hcbiochemLv 72 months agoFavorite Answer
The image below shows the form of the molecule in its unionized form. At physiological pH, the alpha-amino group of the glutamyl residue is protonated and positively charged, and the two carboxyl groups (the terminal one of glycine and the alpha-carboxyl group of the glutamyl residue) are both ionized and negatively charged. Thus the molecule has a net charge of -1 at physiological pH.