Dissolved oxygen (dO2) in E. coli BW25113 cultures were continuously measured directly in the flasks using a Clarke oxygen electrode InPro 6800 (Mettler Toledo). The dO2/pH controller of a BioFlo 110 fermentor (New Brunswick Scientific Co., USA) was used for data recording.
Redox potential (Eh) in the cell-free medium and E. coli cultures was continuously measured directly in the flasks using platinum and reference electrodes and Mettler Toledo SevenCompact™ pH/Ionmeters S220.
Changes in the levels of extracellular K+ were continuously registered directly in the flasks using the system of K+-selective (ELIS-121K) and reference electrodes and a computer pH/ion meter cpX-2 (IBI Pushchino, Russia). For K+ measurements, E. coli cells were grown as described above, except that the medium contained a low K+ concentration (0.1 mM).
Extracellular sulfide levels were detected directly in the flasks using the system of sulfide-specific ion-selective XC-S2-001 (Sensor Systems Company, Russia) and reference electrodes and a computer pH/ion meter cpX-2 (IBI Pushchino, Russia).
Redox potential (Eh) in the cell-free medium and E. coli cultures was continuously measured directly in the flasks using platinum and reference electrodes and Mettler Toledo SevenCompact™ pH/Ionmeters S220.
Changes in the levels of extracellular K+ were continuously registered directly in the flasks using the system of K+-selective (ELIS-121K) and reference electrodes and a computer pH/ion meter cpX-2 (IBI Pushchino, Russia). For K+ measurements, E. coli cells were grown as described above, except that the medium contained a low K+ concentration (0.1 mM).
Extracellular sulfide levels were detected directly in the flasks using the system of sulfide-specific ion-selective XC-S2-001 (Sensor Systems Company, Russia) and reference electrodes and a computer pH/ion meter cpX-2 (IBI Pushchino, Russia).