BPS2026 – Lifetime-based multiparameter fluorescence spectroscopy one phytoplankton cell at a time

Aquatic phytoplanktons are in charge of the majority of photosynthesis on Earth and serve as the main contributors to primary productivity. Cells of these species carry molecular systems that specialize in funneling excitation energy for use in photosynthesis-related charge separation and subsequently respiration. These systems include photosystems embedded in membranes, and phycobilisomes on top of photosystems to optimize funneling of energy from the visible range of the electromagnetic spectrum. Such well-controlled, highly efficient use of light is driven by the spatial organization of specific pigments and by excitation energy transfer between them at different coupling regimes. As such, the autofluorescence of unicellular phytoplankton species is meaningful and therefore can be used for identifying different species and their metabolic responses to certain environmental changes. In this talk, I will showcase a single-cell time-resolved multiparameter fluorescence spectroscopy approach to track photo-physiological changes that phytoplankton species undergo when acclimating to different external stresses with direct relevance to ecology in general and the rise of algal blooms in particular.