Abstract: The present disclosure relates to methods and materials for determining an isoelectric point for a protein including, for example, a binding molecule such as an antibody. The isoelectric points may be used in methods for the preparation of proteins. Such methods may comprise identifying amino acid residues that are exposed on the surface of the protein in a sequence of amino acid residues of the protein, assigning a pKa value to the surface exposed amino acid residues, and calculating the isoelectric point of the protein from the pKa values assigned to the surface exposed amino acid residues. The methods of the present disclosure may be used for selecting and utilizing a buffer for purification of a protein, preparing a protein formulation, purifying a protein and/or stabilizing a protein in solution.

Abstract: The present disclosure provides methods and apparatus for displaying an alphabetic string representing an amino acid sequence of an antibody in association with predicted characteristics of certain sites in the antibody. In an embodiment, a process causes a web based application server to receive an alphabetic string from a client device indicative of an amino acid sequence. The server then predicts sites in the amino acid sequence likely to be associated with certain chemical properties such as deamidation, glycosylation, oxidation, proteolysis, and isomerization. The server may also predict other characteristics such as domain boundaries, binding sites, hydrophobicity levels, surface exposures, etc. The server then sends data to the client device indicative of the predicted sites and characteristics, so that the client device can display the alphabetic string indicative of the amino acid sequence with a graphical indication of the position of each predicted chemical property (e.g.