TY  - JOUR
A1  - Spijkerman, Elly
A1  - Lukas, Marcus
A1  - Wacker, Alexander
T1  - Ecophysiological strategies for growth under varying light and organic carbon supply in two species of green microalgae differing in their motility
JF  - Phytochemistry : an international journal of plant biochemistry
N2  - Mixing events in stratified lakes result in microalgae being exposed to varying conditions in light and organic carbon concentrations. Stratified lakes consist of an upper illuminated strata and a lower, darker strata where organic carbon accumulates. Therefore, in this contribution we explore the importance of dissolved organic carbon for growth under various light intensities by measuring some ecophysiological adaptations in two green microalgae. We compared the non-motile Chlorella vulgaris with the flagellated Chlamydomonas acidophila under auto-, mixo-, and heterotrophic growth conditions. In both algae the maximum photosynthetic and growth rates were highest under mixotrophy, and both algae appeared inhibited in their phosphorus acquisition under heterotrophy. Heterotrophic conditions provoked the largest differences as C. vulgaris produced chlorophyll a in darkness and grew as well as in autotrophic conditions, whereas Chl. acidophila bleached and could not grow heterotrophically. Although the fatty acid composition of both phytoplankton species differed, both species reacted in a similar way to changes in their growth conditions, mainly by a decrease of C18:3n-3 and an increase of C18:1n-9 from auto- to heterotrophic conditions. The two contrasting responses within the group of green microalgae suggest that dissolved organic carbon has a high deterministic potential to explain the survival and behaviour of green algae in the deeper strata of lakes.
KW  - Chlamydomonas acidophila
KW  - Chlorella vulgaris
KW  - Chlorophyceae
KW  - Ecophysiology on freshwater phytoplankton
KW  - Glucose
KW  - Mixotrophy
KW  - Osmotrophy
KW  - Heterotrophy
KW  - Photosynthesis
KW  - Fatty acids
Y1  - 2017
U6  - https://doi.org/10.1016/j.phytochem.2017.08.018
SN  - 0031-9422
SN  - 1873-3700
VL  - 144
SP  - 43
EP  - 51
PB  - Elsevier
CY  - Oxford
ER  -