Influence of high hydrostatic pressure on the reaction between glyoxal and lysine residues

To investigate the influence of high hydrostatic pressure on the reactions of glyoxal with lysine residues, the formation of end-products, namely N-epsilon-(carboxymethyl)lysine (CML) and 1,3-bis(5-amino-5-carboxypentyl)imidazolium salt (GOLD), was studied in model systems via LC-MS. Following a kinetic interpretation, reaction volumes were calculated. Corresponding values of +5.4 (CML) and +9.9 cmA(3)/mol (GOLD) indicate a suppressive effect of pressure on the formation of these glycation compounds. Above this, several other known end-products, namely N(6)-glycoloyllysine (GALA), N(6)-[2-[(5-amino-5-carboxypentyl)amino]-2-oxoethyl]lysine (GOLA), and reaction intermediates, were qualitatively monitored and proofed a similar behavior compared to the GOLD formation pathway. The reasons for the influence of pressure are discussed in the context of the reaction mechanism.