Fast atom bombardment/tandem mass spectrometry of physalaemin-like peptides

Abstract

Fragment ion spectra obtained from collision-induced decomposition of protonated molecular ions have been used to determine amino acid sequences of several physalaemin-like peptides which were recently purified from rabbit stomach. This technique was chosen because the peptides were available in microgram quantities and were anticipated to contain pyroglutamate as the blocked N-terminal residue. Such spectra of several synthetic analogs of the naturally occurring peptides were obtained and analyzed to confirm the veracity of this peptide sequencing strategy. In addition, methyl ester derivatives of these synthetic peptides provided a crucial test for the spectral interpretation via the mass shifts thus induced.

Computer-based mass measurement of fragment ion spectra from tandem magnetic sector mass spectrometers with an electrically floated collision cell

“…This example demonstrates the power of the techniques used in the present work. Fragment ions, other than the sequence ions discussed here, also are formed and will be discussed elsewhere (12).…”

From physical chemistry to mass spectrometry to government lab manager in half a century

“…Fortunately for us the biochemists had microgram amounts available so the low sensitivity of our FAB‐MS/MS technique did not prevent us from obtaining useful data. Several analogs of the naturally occurring peptides were synthesized and analyzed to confirm the validity of our assigned sequences, and methyl ester derivatives of these synthetic peptides provided a crucial test for the spectral interpretation via the resulting mass shifts (Harvan et al, ). This was an early (1984) attempt at peptide sequencing by mass spectrometry (publication was delayed by my whirlwind sabbatical at Swansea followed almost immediately afterwards by my move from Guelph), and looks primitive by modern standards.…”