An outbreak of food poisoning was recently reported in a local university cafeteria. Researchers at the CDC and the FDA discovered that some of the vegetables were being left out too long and this caused problems in a specific variety of frozen peas that contained the protein.
N'-NASTYPEAS -C'
Researchers first desired to understand the structure of this peptide at a pH of 7.5 . Researchers knew that the pKas for this peptide were 10.46, 8.72, 4.07, and 2.20

a. Draw the complete structure of this peptide with the titratable groups in the predominant protonation state at pH12. Please specify stereochemistry on the backbone atoms.