Fast atom bombardment mass spectrometry of bradykinin and related oligopeptides

Abstract

The new technique of fast atom bombardment mass spectrometry has been applied to bradykinin, lysyl-bradykinin and methionyl-lysyl-bradykinin. High sensitivity was obtained at [M + H]+ in the positive ion spectra with a comparable response at [M—H]− in the opposite polarity. All spectra contained an abundance of structurally significant fragment ions. Schemes for relating the observed fragments to the known amino acid sequences are reported for all three molecules. Mass spectrometric investigations on bradykinin were followed by quantitative bioassays which showed that atom bombardment for ten minutes had no measurable effect on the biological activity of microgram samples.