Mass spectrometry analysis of peptides translated from amplicons obtained with primers HCFLAGALA and HCFLAG-4. (A) Peptide obtained from template pCV-H77C. The predicted mass of the peptide, after methionine cleavage and N-terminal acetylation, is 7,102 Da. (B) Peptide obtained from template pCV-J4L6S. The predicted mass, after methionine cleavage and N-terminal acetylation, is 7,206 Da. (C) Peptides obtained from mixing the amplicons of pCV-H77C and pCV-J4L6S. (D) Peptides obtained from the H-77 serum aliquot.