Binding of benzyl penicilloyl to human serum albumin Evidence for a highly reactive region at the junction of domains 1 and 2 of the albumin molecule

Tryptic digests of fragment C124–298of penicilloylated serum albumin, obtained from a penicillin‐treated patient or prepared by in vitro conjugation, were analyzed by HPLC. Determinations of benzyl penicilloyl groups (BPO) were performed on the different fractions. Three BPO‐containing peptides were identified by their amino acid sequence and the bound BPO was located on lysines 190, 195 and 199 and serine 193. These four main BPO‐binding sites are all located on a very short region (10 amino acid residues) of the albumin molecule at the junction of domains 1 and 2.