Biomedical Engineering: Bridging Medicine and Technology 1st Edition by Veronique Tran,Mark Saltzman

Exercise 11

Cells have surface receptors that can recognize and bind to the tripeptide RGD (Arg-Gly-Asp). Tissue engineers sometimes use this adhesive peptide to render synthetic biomaterials attractive to cells.
a. Draw the chemical structure of the RGD peptide.
b. Write the acid ionization chemical equation for each ionizable group. Use the Henderson-Hasselbalch equation to determine the ionization state of each ionizable group at pH 7.4. Be sure to consider ALL the ionizable
c. What is the net charge of the RGD peptide at physiological pH?