Methylglyoxal Detoxification Revisited: Role of Glutathione Transferase in Model Cyanobacterium <i>Synechocystis</i> sp. Strain PCC 6803
Xavier Kammerscheit, Arnaud Hecker, Nicolas Rouhier, Franck Chauvat, Corinne Cassier‐Chauvat
Abstract
In most organisms, methylglyoxal (MG), a toxic metabolite by-product that causes diabetes in humans, is predominantly detoxified by the glyoxalase enzymes. This process begins with the so-called "spontaneous" conjugation of MG with the cytoprotectant metabolite glutathione (GSH). In this study, we unravel a logical, but as yet unsuspected, link between MG detoxification and a (prokaryotic) representative of the ubiquitous glutathione transferase (GST) enzymes. We show that a GST of a model cyanobacterium plays a prominent role in the detoxification of MG in catalyzing its conjugation with GSH. This finding is important because this reaction, always regarded as nonenzymatic, could exist in plants and/or human and thus have an impact on agriculture and/or human health.