Origin and structure
BPC-157 is a synthetic pentadecapeptide — fifteen residues, sequence GEPPPGKPADDAGLV — described as a partial sequence of body protection compound isolated from gastric juice. It is unmodified: no terminal acetylation, no amidation, no non-natural residues, with a molecular weight of approximately 1419 Da.
That structural simplicity is relevant to handling. Without stabilising modifications the peptide relies on its proline-rich composition for resistance to enzymatic degradation, and it is notably stable in acidic conditions relative to most short peptides of comparable length.