A tripeptide is a peptide derived from three amino acids joined by two or sometimes three peptide bonds. As for proteins, the function of peptides is determined by the consistuent amino acids and their sequence. The simplest tripeptide is glycylglycylglycine. In terms of scientific investigations, the dominant tripeptide is glutathione (γ-L-Glutamyl-L-cysteinylglycine), which serves many roles in many forms of life. A tripeptide is a peptide derived from three amino acids joined by two or sometimes three peptide bonds. As for proteins, the function of peptides is determined by the consistuent amino acids and their sequence. The simplest tripeptide is glycylglycylglycine. In terms of scientific investigations, the dominant tripeptide is glutathione (γ-L-Glutamyl-L-cysteinylglycine), which serves many roles in many forms of life.