Application of fast atom bombardment mass spectrometry to posttranslational modifications of neuropeptides

FABMS is a powerful and sensitive analytical technique capable of providing structural information unattainable by standard methods of peptide analysis. Many posttranslational modifications are undetectable by other routine analytical methods. In addition, FABMS is capable of providing information regarding posttranslational modifications at levels of peptide comparable to those required for other methods of analysis (10-1000 pmol). FABMS has had the effect on protein structure analysis that structure determination of any neuropeptide might now be considered incomplete without some form of mass spectrometric analysis. Much of the recent explosive increase in the use of mass spectrometry for solving problems in peptide structure analysis can be traced to improvements in methods capable of producing molecular ions from nonvolatile species. With the development of these methods, it can be expected that refinements of existing methods and new ionization methods will continue to increase the mass range and sensitivity available for peptide structure determination. For a brief review of other mass spectrometric methods applicable to peptides, see Delgass and Cooks.