Figure 3 | Scientific Reports

Figure 3

From: Addition of anaerobic electron acceptors to solid media did not enhance growth of 125 spacecraft bacteria under simulated low-pressure Martian conditions

Figure 3

Growth of bacteria (species are listed in Fig. 2 and Table S1) on TSA plates under four different incubation conditions (top headings) and five different media (rows). A total of 25 spacecraft isolates were tested on each agar plate. All TSA plates contained the same bacteria. (A) The first column shows results of growth at low-PTA conditions (only one set of replicate plates are shown here); and only the positive-control, Serratia liquefaciens ATCC 27,592 grew (red arrows in column 1). The second set of columns shows results at 1013 hPa, 0 °C, and Earth-normal pO2. The third set of columns shows results for growth at 1013 hPa, 0 °C, and CO2-enriched anoxic atmospheres. And the fourth set of columns shows results after incubation at 1013 hPa, 30 °C, and Earth-normal pO2. The first three sets were incubated for 28 days, the last set was incubated for 24 h. The rows depict (A) TSA, (B) TSA + vitamins and minerals, (C) TSA + nitrate, (D) TSA + sulfate, and (E) TSA + Fe3+, pH 5. Arrows indicated positive growth with minimal microbial activity in the assays.

Back to article page