Non-enzymatic Krebs cylce-like reactions detected by 1H-NMR
These are the raw 1H-NMR datafiles for the experiments presented in the article "Primordial Krebs-cycle-like non-enzymatic reactions detected by mass spectrometry and nuclear magnetic resonance", by Markus A. Keller, Paul C Driscoll, Christoph Messner, Markus Ralser, as appearing in Wellcome Open Research.
Steps to reproduce
100 μM isocitrate or ɑ-ketoglutarate were incubated in water bath at 70°C in the presence of 200 μM ammonium peroxydisulfate for 0, 45, 105, 180, 285, and 320 minutes (total volume for each time point 1 ml). Incubations were conducted in 2 ml microcentrifuge tubes, stopped by cooling the reaction mixture. For 1H-NMR analysis, samples were prepared at a volume of 500 μl in 5 mm NMR tubes, contain 5% D2O for field-frequency lock. One-dimensional 1H NMR experiments were conducted at either 600 (Avance III) or 700 MHz with (Avance IIIHD) spectrometers (Bruker Daltonics) equipped with 5mm TCI or QCI cryoprobes at 25 °C, as indicated. A standard excitation sculpting (zgesgp) 39 pulse sequence was employed with typical acquisition parameters: sweepwidth 20 ppm; relaxation delay 2 s; acquisition time 3 s (84584 complex data points); 4 dummy scans; 256 transients; total measurement time 22 mins. Free induction decays were apodized with 2 Hz line broadening, and zerofilled to 128K complex points prior to Fourier transformation. For LOD measurements conducted on the Avance IIIHD, the number of transients was increased up to 1440; total measurement time 2 h 2 m.