Fig. 2

Evolution of the biomass estimated in gram of dry cell weight (DCW) per liter of growth medium (a), and intracellular iron concentration (b), during the growth step under pH–stat fed-batch culture lasting 140 h, starting the fermentation using unfrozen MSR1 originating from a freshly obtained CCB (unfrozen CCB), unfrozen MSR1 originating from a freshly prepared PCB (unfrozen PCB), unfrozen MSR1 from the PCB stored during 16 months at − 80 °C (16 months stored PCB). The error bar originates from the cultures that were carried out in duplicate