|Section2= |Section3= }} Bradykinin is a physiologically and pharmacologically active peptide of the kinin group of proteins, consisting of nine amino acids. Structure Bradykinin is a 9-amino acid peptide chain. The amino acid sequence of bradykinin is: Arg - Pro - Pro - Gly - Phe - Ser - Pro - Phe - Arg. Its empirical formula is therefore C50H73N15O11. Synthesis The kinin-kallikrein system makes bradykinin by proteolytic cleavage of its kininogen precursor, high-molecular-weight kininogen (HMW… (More on Bradykinin)