Extended Data Fig. 2 |. Mn(II) oxidation and growth by the co-culture.

a, DNA yield of the two species co-culture incubated in MOPS-buffered basal media in the absence of Mn(II) substrate. No statistically significant changes in the mean DNA yields (p=0.06, day 0 vs 10; p=0.70, day 10 vs 21; p=0.20, day 0 vs 21; two-tailed t-test with equal variance) are observed over the incubation period. b, c, Exponential increase in Bacteria and biomass yields in a Mn(II)-oxidising culture, which is coupled to exponential increases Mn(II) oxidation (same culture analysed in Fig. 2). Bacteria was measured via 16S rRNA gene copies using a general Bacteria probe in quantitative PCR; points represent 3 technical replicates. Biomass was measure via DNA yield from same culture volumes. d, Exponential increases in Mn(II) oxidation (Fig. 2a) and DNA yields by this same culture (1 mM nitrate replicate 1, c) correlate. Similar relationships were observed in samples from independent cultivation experiments (n=2). e-l, Kinetics of Mn(II) oxidation by the co-culture in basal media; two phases of exponential Mn(II) oxidation were observed. e-g, Basal media with 1 mM nitrate (n=4; for replicate 1, see b–d and Fig. 2). h-l, Basal media with 1 mM ammonia (n=5). m, Exponential growth of Species A and Species B paralleled Mn(II) oxidation in basal medium with 1 mM ammonia as N source (1 mM ammonia replicate 5, l), rather than 1 mM nitrate. n, Linear relationship between cell growth and the amount of Mn(II) oxidised (1 mM ammonia replicate 5, l and m). Values in n were normalised by subtracting the initial cell number and Mn oxide concentrations at the onset of the experiment, and negative values after normalisation were excluded from the analysis. All data points included in the line fits are used to calculate the doubling times (T_d), unless otherwise noted by x symbols.