Optimization of guanidination procedures for MALDI mass mapping.
Improved procedures for guanidination of lysine-containing peptides, a derivatization that results in increased MALDI mass spectral signal intensities are presented. The complete conversion of lysines to homoarginines can be accomplished in as little as 5 min. The method is demonstrated on a model peptide and on tryptic digests of three proteins. To demonstrate the applicability to proteomics samples, it is successfully applied to the digest of 50 fmol of a protein. Approaches for concentrating and purifying low-quantity protein digests following guanidination are evaluated. Experiments with the model peptide GRGDSPK enable investigation of the specificity of the guanidination reaction.
Beardsley
Richard L
RL
Department of Chemistry, Indiana University, Bloomington 47405, USA.
Reilly
James P
JP
D003574:Cytochrome c Group / Q000737:chemistry; D008401:Gas Chromatography-Mass Spectrometry / Q000379:methods; D006146:Guanidines / Q000737:chemistry*; D008239:Lysine / Q000737:chemistry; D009211:Myoglobin / Q000737:chemistry; D010449:Peptide Mapping / Q000379:methods*; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization / Q000379:methods*
D003574:Cytochrome c Group; D006146:Guanidines; D009211:Myoglobin; D008239:Lysine