Growth rates of UWO241 and C. reinhardtii at different
steady-state temperatures
We compared the effects of temperature on growth in the psychrophile
UWO241 and the mesophile C. reinhardtii . The growth rate of
UWO241 cultured at 4°C (the approximate temperature in its natural
environment) was 0.019 h-1; however, maximal growth
rates were achieved at 10°-15°C (0.025-0.030 h-1;
Figure 1A). We observed lower growth rates in UWO241 at 17°C (0.013
h-1), and no growth was observed at 20°C. In
accordance with previous reports (Schroda, Hemme & Mühlhaus 2015),C. reinhardtii exhibited maximal growth rates when cultured at
28°C (0.048 h-1) and lower rates at growth
temperatures both higher and lower than this range (Figure 1B). Despite
a longer lag phase (not shown), C. reinhardtii cultures were able
to grow at 10° and 15°C, albeit at a decreased rate (0.025 and 0.034
h-1, respectively) compared to growth at 28°C (Figure
1B). This low temperature growth rate for C. reinhardtii was
comparable to the maximum growth rates of UWO241 between 10°-15°C
(Figure 1A). We did not observe growth of the mesophilic alga at 5°C or
40°C.