Fractionation and Characterization of Basic Proline-Rich Peptides of Human Parotid Saliva and the Amino Acid Sequence of Proline-Rich Peptide P-E

Basic proline-rich peptides of human parotid saliva were fractionated and characterized. The amino acid sequence of one of the purified peptides, P-E, was determined to be SPPGKPQGP$P10$PQGGNQPQG$P20$PPPPGKPQG$P30$PPQGGNRPQ$G40$PPPPGKPQG$P50$PPQGDKSRS$P60$R. The results demonstrate the repetitiveness of the partial sequence within the molecule and the occurrence of structures common to those of other salivary poly-peptides such as P-C and Protein C.