Trivalent Standard Amino Acid with Non-interactive Acid/Base Titration Equilibrium Reactions

Download and install the CDF Player: If the lastest version of the Wolfram Mathematica Computable Document Format or CDF player is not already installed on your computer, CLICK HERE to download the CDF Player installation file, install it, and then configure your computer to open "*.CDF" files by defalut with the Player. For example, the image shows how to select the default app setting in Windows 10. Download and open the CDF activity file: Download the following CDF activity file into a folder you can easily find - Trivalent Ligand Binding v3.1.[source]-header.cdf - and then open it with the stand-alone CDF Player. Nested titration plots: As illustrated by the static image below, the first nested titration plot records the saturation fraction (Ya) vs. pH (top X-axis) or vs. [H+] (bottom X-axis) of Aspartate, one of 7 trivalent standard amino acids with three ionizable groups, i.e., its α-amino (NH3+), α-carboxyl (COOH), and sidechain R groups. The colored vertical dashed lines identify their equilibrium dissociation constants - pKN(NH3+), pKC(COOH), and pKR - and the black vertical dashed line identifies the isoelectric pH (pI) of this AA.. Use the pulldown menu (lower arrow) to navigate through the nested titration plots for the other trivalent AAs.

Static image of the top-nested plot displayed after the CDF activity file is opened with the Player.
Nicholas Clayton and Duane W. Sears (c) 2011, University of California Santa Barbara.