Fig. 2.
Chemical synthesis of the wild-type HIV-1 protease and analogues was based on the native chemical ligation of two synthetic peptide segments.11 (Upper) Synthetic scheme. In the Scheme, MPaArg4 = 3-mercaptopropionate tetraarginine.amide (i.e. the thioester leaving group). (Lower) Analytical LCMS data for the synthetic enzyme with Gly51/51’.