FAB Mass Spectrometric Detection of ε( γ -Glutamyl)Lysine Crosslinks and ( γ -Glutamyl)Polyamine Derivatives Produced by Transglutaminase in Vitro
The identification of both acyl donor and acceptor substrates, as well as the detection of ε( γ -glutamyl)lysine crosslinks and ( γ-glutamyl) amine derivatives, are some of the most important aspects in the field of the transglutaminase (TGase)-mediated reactions1–5. These reactions have been revealed so far using both direct and indirect methodologies. The main direct method is based upon chromatographic isolation and identification of the isopeptide ε( γ -glutamyl)lysine or of ( γ -glutamyl)amine derivatives after exhaustive proteolytic digestion of the reaction products. On the other hand, the detection of either polymers or radioactive amine-protein adducts by SDS-PAGE, together with the protein crosslinking inhibition by small molecular weight amines, represent the most commonly used indirect methodologies. However, both procedures suffer from severe limitations since a single analytical system does not yield unambiguous results.
KeywordsLysine Residue Fast Atom Bombardment Acyl Donor Acceptor Substrate Glutamine Residue
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- 2.J. E. Folk, Mechanisms and basis for specificity of transglutaminase-catalyzed epsilon(gamma-glutamyl)lysine bond formation, in: “Advances in Enzymology and Related Areas in Molecular Biology,” Meister, A. ed., Wiley, New York (1983).Google Scholar
- 5.A. G. Loewy, The Nε-(γ-glutamic)lysine cross-link: method of analysis, occurrence in extracellular and cellular proteins, in: “Meth. Enzymol.” 107:241, Academic Press, Inc, New York (1984).Google Scholar
- 6.A. Dell and M. Panico, Fast Atom Bombardment mass spectrometry of biomolecules, in: “Mass Spectrometry in Biomedical Research,” S. Gaskell, ed., J. Wiley and sons, Chichester (1986).Google Scholar