title: Metabolism of AGEs--bacterial AGEs are degraded by metallo-proteases.
abstract: Advanced Glycation End Products (AGEs) are the final products of non-enzymatic protein glycation that results in loss of protein structure and function. We have previously shown that in E. coli AGEs are continually formed as high-molecular weight protein complexes. Moreover, we showed that AGEs are removed from the cells by an active, ATP-dependent secretion and that these secreted molecules have low molecular weight. Taken together, these results indicate that E. coli contains a fraction of low molecular weight AGEs, in addition to the high-molecular weight AGEs. Here we show that the low-molecular weight AGEs originate from high-molecular weight AGEs by proteolytic degradation. Results of in-vitro and in vivo experiments indicated that this degradation is carried out not by the major ATP-dependent proteases that are responsible for the main part of bacterial protein quality control but by an alternative metal-dependent proteolysis. This proteolytic reaction is essential for the further secretion of AGEs from the cells. As the biochemical reactions involving AGEs are not yet understood, the implication of a metalloprotease in breakdown of high molecular weight AGEs and their secretion constitutes an important step in the understanding of AGEs metabolism.
authors.affiliation: Department of Molecular Microbiology and Biotechnology, Life Sciences, Tel Aviv University, Tel Aviv, Israel.
authors.forename: Ifat
authors.initials: I
authors.lastname: Cohen-Or
authors.forename: Chen
authors.initials: C
authors.lastname: Katz
authors.forename: Eliora Z
authors.initials: EZ
authors.lastname: Ron
mesh_terms: D001149:Arsenates / Q000494:pharmacology; D002701:Chloramphenicol / Q000494:pharmacology; D004926:Escherichia coli / Q000187:drug effects / Q000378:metabolism; D017127:Glycation End Products, Advanced / Q000378:metabolism*; D008666:Metalloendopeptidases / Q000037:antagonists & inhibitors
chemical_list: D001149:Arsenates; D017127:Glycation End Products, Advanced; D002701:Chloramphenicol; D008666:Metalloendopeptidases; C025657:arsenic acid