Physalaemin-like immunoreactive peptides from rabbit stomach

Two physalaemin (PHY)-like immunoreactive peptides, designated PHLIPs, have been purified from extracts of rabbit stomach tissue. Fast atom bombardment/ mass spectrometry (FAB/MS) indicated that the m/z values for the PHLIP pr-tonated molecular ions were 867.419 and 796.4. FAB/tandem MS spectra, coupled with a knowledge of the amino acid composition and the aid of a computerized fragment-matching program, indicated the amino acid sequences to be: < Glu-Val-Asp-Pro-Asn-Ile-Gln-Ala PHLIP-8, and < Glu-Val-Asp-Pro-Asn-Ile-Gln PHLIP-7 The sequences of PHLIPs-7 and -8 were confirmed with synthetic peptides. The PHY-antiserum cross-reactivity of the PHLIPs reflects homology at amino acid residues 1, 3, 4 and 5 for the mammalian and amphibian residues.