Strains and Growth Conditions
Chlamydomonas sp. UWO241 and Chlamydomonas reinhardtii(cc-1690) were grown axenically in Bold’s Basal Medium (BBM)
supplemented with 10 mM NaCl. All cultures were aerated continuously
with ambient air filtered by a 0.2 µm filter in 250 ml glass growth
tubes suspended in thermo-regulated aquaria. A continuous growth
irradiance of 130 µmol photons m-2s-1 was generated by fluorescent tubes (Sylvania
CW-40) and measured with a quantum sensor attached to a radiometer
(Model LI-189; Li-Cor). Algal cultures were exposed to heat stress by
transfer to aquaria maintained at 24°C (UWO241) and 42°C (C.
reinhardtii ). Mid-log cultures were used in all experiments.