Discrimination and selective enhancement of signals in the MALDI mass spectrum of a protein by combining a matrix-based label for lysine residues with a neutral matrix.

Protein Mass Spectrometry Laboratory, Institut de Biologie Structurale, CEA, CNRS, UJF, UMR 5075, 41 rue Jules Horowitz, 38027 Grenoble Cedex 1, France.
Angewandte Chemie International Edition (Impact Factor: 11.34). 02/2007; 46(29):5594-7. DOI: 10.1002/anie.200700811
Source: PubMed

ABSTRACT Discrimination with a difference: The N-hydroxysuccinimide ester of HCCA (α-cyano-4-hydroxycinnamic acid) was used as a labeling reagent to increase the MALDI MS signal of weakly concentrated peptides of interest in a proteolytic mixture derived from cytochrome c relative to the signals of other peptides. The desired effect was only observed with the neutral MALDI matrix HCCE.

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