Figure 1.

Linear growth in low-metal environment. (A) Exponential growth observed in non-limiting conditions (rich). Cells were grown in rich medium and were counted using automatic image analysis software. Shown is the number of cells in a field of view. The red dashed line is an exponential fit (r²=0.9994). Doubling time of 103 min was extracted from the fit. (B) Linear growth observed in LZM. Cells were grown in low-zinc conditions (LZM+10 μM Zn²⁺) and counted as above. Zinc was replenished at t=10 h, following which the cells resumed exponential growth. The dashed red line is a linear fit to the linear part of the growth curve (r²=0.9985), see also Supplementary Figure 1b. Linear behavior was observed also in batch cultures (see Supplementary Figure 1b). We performed the same experiment where for the rich medium we used LZM+300 μM Zn²⁺ instead of SC (see Supplementary Figures 2a and b). (C) Linear growth observed in low-iron conditions. Cells were grown in low-iron conditions (Methods) and counted as above over three different fields of view. (D) Linear growth observed in low-copper conditions. Same as (C) for low-copper conditions (Methods). (E) No linear growth was observed in low phosphate conditions. Same as (C) for low-phosphate conditions (Methods).