[The effect of Maillard reaction products on enzyme reactions].

In this article current knowledge about the Maillard reaction in vivo is described first, especially the glycosylation reactions of various tissues and the identification of different final products and intermediates of Maillard reaction. The influence of MRP on digestion is of significant importance. These products are absorbed in different ways and are excreted in various amounts. Hence, the organism is variably influenced by MRP. The influence of defined MRP, of glycosylated proteins and of melanoidins on glycosidases and proteases is described. The effects produced depend on the enzyme and on the used MRP. Reactive alpha-dicarbonyl compounds play an important role in the organism. Further possible reactions of these compounds caused by reductases are discussed. The protein structure of enzymes is changed by Maillard reaction. Thereby the enzyme activity is influenced by covalent modifications of different amino acids and by inter- and intramolecular crosslinking. Finally, the use of enzymes and monoclonal antibodies for detection of MRP is discussed.