Premium
Analysis of Protein Glycation Products by MALDI‐TOF/MS
Author(s) -
KISLINGER THOMAS,
HUMENY ANDREAS,
PEICH CARLO C.,
BECKER CORDMICHAEL,
PISCHETSRIEDER MONIKA
Publication year - 2005
Publication title -
annals of the new york academy of sciences
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.712
H-Index - 248
eISSN - 1749-6632
pISSN - 0077-8923
DOI - 10.1196/annals.1333.030
Subject(s) - chemistry , peptide , amadori rearrangement , glycation , lysozyme , maillard reaction , matrix assisted laser desorption/ionization , lysine , mass spectrometry , methylglyoxal , chromatography , pentosidine , protein mass spectrometry , residue (chemistry) , biochemistry , tandem mass spectrometry , desorption , enzyme , amino acid , organic chemistry , receptor , adsorption
A bstract : Matrix‐assisted laser desorption ionization‐mass spectrometry with time‐of‐flight detection (MALDI‐TOF/MS) is a promising tool to analyze advanced glycation end product (AGE)‐modified proteins. The combination of soft ionization (MALDI) with time‐of‐flight mass detection allows analysis of peptides and proteins of a molecular mass up to 300 kDa with minimal sample workup. Because the direct structural analysis of intact AGE proteins is not possible due to the formation of broad and poorly resolved peaks, peptide mapping was introduced into the analysis of AGE proteins by MALDI‐TOF/MS, allowing site‐specific analysis of defined AGEs. When methylglyoxal‐modified lysozyme was subjected to MALDI‐TOF/MS peptide mapping, methylimidazolone and argpyrimidine attached to the arginine residue and carboxyethyl (CEL) bound to the lysine were detected on peptide aa1‐7 ( K VFG R CE). In contrast, only one methylimidazolone was found on peptide aa8‐35 (LAAAM KR HGLDNY R GYSLGNWVCAA K FE) and peptide aa120‐129 (VQAWI R GC R L), respectively. The analysis of AGE protein, which had been incubated with glucose, revealed the presence of an Amadori product and a carboxymethyl residue (CML) on peptide aa1‐7 and peptide aa8‐35 , as well as an imidazolone A on peptide aa120‐129 . Furthermore, the early Maillard reaction of lysozyme, which had been glycated by seven different sugars, was monitored by MALDI‐TOF/MS peptide mapping. Finally, this approach was successfully applied for site‐ and product‐specific relative quantification of AGEs. For example, kinetics of CML and Amadori product formation on peptide aa1‐7 , as well as imidazolone A formation on peptide aa120‐129 , were determined.