Schrøder, Tine Daa4; Özalp, Veli Cengiz4; Lunding, Anita4; Jernshøj, Kit Drescher5; Olsen, Lars Folke4
1 Department of Biochemistry and Molecular Biology, Faculty of Science, SDU2 Institute of Chemical Engineering, Biotechnology and Environmental Technology, Faculty of Engineering, SDU3 Institute of Sensors, Signals and Electrotechnics, Faculty of Engineering, SDU4 Department of Biochemistry and Molecular Biology, Faculty of Science, SDU5 Institute of Sensors, Signals and Electrotechnics, Faculty of Engineering, SDU
We have studied oscillating glycolysis in the strain BY4743 and isogenic strains with deletions of genes encoding enzymes in glycolysis, mitochondrial electron transport and ATP synthesis. We found that deletion of the gene encoding the hexokinase 1 isoform does not affect the oscillations while deletion of the gene encoding the hexokinase 2 isoform results in oscillations with smaller amplitude. The latter is associated with an almost 50% decrease in hexokinase activity. Deletions in the genes encoding the α- and β-subunits of phosphofructokinase abolish the oscillations entirely. This loss in oscillatory activity is associated with a fourfold decrease in phosphofructokinase activity. Deletions of genes encoding subunits of the F1F0 ATPase also inhibit the oscillations in accordance with earlier studies using for example inhibitors. Finally, we identified an apparently new control point involving the mitochondrial cytochrome c oxidase. The latter is difficult to explain as oscillatory activity entails 100% inhibition of this enzyme. The mitochondria of this strain seem to have normal F1F0 ATPase activity. Overall these results support earlier experimental and model studies suggesting that in addition to processes within glycolysis also processes outside this pathway contribute to the control of the oscillatory behaviour.
Febs Journal, 2013, Vol 280, Issue 23, p. 6033-6044