FRUCTATED PROTEIN IS MORE RESISTANT TO ATP-DEPENDENT PROTEOLYSIS THANGLUCATED PROTEIN POSSIBLY AS A RESULT OF HIGHER CONTENT OF MAILLARD FLUOROPHORES

Glycation by fructose (fructation) renders bovine serum albumin more r efractory to degradation by an ATP-dependent proteolytic system from r eticulocytes than glycation by glucose (glucation), It appears that th e decrease in the protein's susceptibility to degradation is a complex effect of the various protein-bound moities that are generated at the different stages of the Maillard reaction and not only the result of primary amino group blockage, Advanced Maillard reaction fluorescent c omponents may induce a decrease in proteolysis, whereas the intermedia te Amadori groups possibly may enhance degradation. However, the inhib itory effect on degradation of the fluorophores would predominate at h igher levels of glycation, Resistance of intracellular fructated prote ins to ATP-dependent degradation may lead to alterations in the functi on of cells with an active sorbitol pathway and, in this way, underlie the complications of diabetes. (C) 1995 Academic Press, Inc.