Immunochemistry of Synthetic Polypeptides and Polypeptidyl Proteins

Summary Bovine albumin, modified by the addition of polypeptides of glutamic acid, lysine, leucine, or phenylalanine was found to be antigenic in rabbits. Evidence is presented to show that antibodies specific for the added peptide modification and for the carrier protein were formed. In addition a third type of antibody may have been formed to the polyleucyl and polyphenylalanyl bovine albumins, which requires the added peptide and at least a part of the carrier protein. Rabbit albumin modified in the same way was also antigenic in rabbits. Antibodies were formed to the polyleucyl and polyphenylalanyl rabbit albumins which were specific for the modification and which also required the added peptide and at least part of the carrier protein. Antisera to the polypeptidyl proteins cross reacted with several purified protein preparations with which antisera to the carrier proteins did not react.