PROTEIN-SEQUENCE AND STRUCTURAL STUDIES EMPLOYING MATRIX-ASSISTED LASER-DESORPTION IONIZATION HIGH-ENERGY COLLISION-INDUCED DISSOCIATION

Matrix-assisted laser desorption ionization (MALDI) is one of the most sensitive ionization methods currently available for the mass spectro metric investigation of a wide range of structural problems involving macromolecules of biomedical significance. This laboratory has recentl y reported the use of MALDI with tandem mass spectrometry and high ene rgy collision-induced dissociation for the unambiguous de novo sequenc e analysis of peptides from an unknown P450 protein [K.F. Medzihradszk y, G.W. Adams, R.H. Bateman, M.R. Green and A.L. Burlingame, J. Am. So c. Mass Spectrom., 7 (1996) 1]. This report describes the characterist ics and the advantages now available using high energy collisional act ivation of MALDI-generated pseudomolecular ions for sequence and struc tural characterization of proteins and covalently modified proteins th at are not accessible under low energy conditions for many types of st ructures. (C) 1997 Elsevier Science B.V.