Abstract
Chlamydomonas raudensis is a psychrotrophic green alga that was isolated from perennially ice-covered lake, Lake Bonny (Antarctica). The lake is covered with a 3-5m ice-cap that transmits only selective wavelengths of light and avoids fluctuation of light intensity. This green alga has been reported to lack the ability of photoacclimation probably due to the extremely stable light environment of the natural habitat. We compared the ability of state transitions in this Antarctic phytoplankton with a model organism Chlamydomonas reinhardtii. The fluorescence quenching profiles and the 77K fluorescence spectra indicate that the two Chlamydomonas species have significantly distinct manner of the energy redistribution between PS1 and PS2. The relationship between the light environment and the photoacclimation mode observed in phytoplankton will be discussed.
