Mixed results with mixed disulfides.
A period of research with Helmut Sies in the 1980s is recalled. Our experiments aimed at an in-depth understanding of metabolic changes due to oxidative challenges under near-physiological conditions, i.e. perfused organs. A major focus were alterations of the glutathione and the NADPH/NADP(+) system by different kinds of oxidants, in particular formation of glutathione mixed disulfides with proteins. To analyze mixed disulfides, a test was adapted which is widely used until today. The observations in perfused rat livers let us believe that glutathione-6-phosphate dehydrogenase (G6PDH), i.a. might be activated by glutathionylation. Although we did not succeed to verify this hypothesis for the special case of G6PDH, the regulation of enzyme/protein activities by glutathionylation today is an accepted posttranslational mechanism in redox biology in general. Our early experimental approaches are discussed in the context of present knowledge.
German Institute of Human Nutrition Potsdam-Rehbruecke, Arthur-Scheunert-Allee 114-116, 14558 Nuthetal, Germany. Electronic address: flohe@dife.de.
Regina
R
Brigelius-Flohé
D004220:Disulfides / Q000378:metabolism*; D005978:Glutathione / Q000378:metabolism; D009249:NADP / Q000378:metabolism; D011499:Protein Processing, Post-Translational
D004220:Disulfides; D009249:NADP; D005978:Glutathione
Glucose-6-phosphate dehydrogenase; Glutathionylation; Mixed disulfides; Nitrofurantoin; Paraquat; Protein thiols