Poster Presentation 21st International Conference on Biological Inorganic Chemistry 2025

15Ν- and 13C-enriched photosynthetic marine diatoms probed by resonance Raman spectroscopy (#411)

Constantinos Varotsis 1 , Charalambos Tselios 1 , Charalambos Andreou 1 , Vasiliki Valianti 2 , Eftychia Pinakoulaki 2
  1. Cyprus University of Technology, Lemesos, PLEASE SELECT, Cyprus
  2. Chemistry, U.of Cyprus, Nicosia, Cyprus

We have characterized 15N- and 13C-enriched marine diatoms and probed their interactions with micro-nano plastics by resonance Raman spectroscopy. Raman marker bands of the marine diatoms have been identified towards our understanding of the effect the micro-nanoplastics exert on the PSI and PSII photosynthetic properties of the diatoms. The growth conditions of the marine diatoms in the presence of microplastics/nanoplastics will be reported and the isotope shifts of the Raman sensitive marker bands will be presented. The pH/pD-dependent fluorescence-excitation spectra of the light-harvesting Fucoxanthin-Chlorophyll a/c-binding proteins (FCPs) of Marine Diatoms will also be reported. A decrease in the energy transfer efficiency from Chlorophylls c1/c2 to Chlorophyll a upon protonation of the 17-acrylates was observed, resembling that observed in marine diatoms under high light conditions. Marine diatoms in addition to their interactions with microplastics accumulate a number of chemical isotopes of 13C, 15NO2, 15NH4, Glucose 13C, and 15NO3.

References

  1. Tselios, C. et al. Evidence for a reversible light-dependent transition in the photosynthetic pigments of diatoms. RSC Advances 23, 31555-31563 (2022).
  2. Andreou, C. et al. Probing the Fucoxanthin-Chlorophyll a/c-Binding proteins (FCPs) of the Marine diatom Fragilariopsis sp. by Resonance Raman spectroscopy. J. Phys. Chem. B127, 9014-9020 (2023).
  3. Andreou, C. and C. Varotsis Light harvesting and photoprotective states in the marine diatom Fragilariopsis sp.: functional implications of chlorophylls c 1/c 2 in the fucoxanthin–chlorophyll a/c-binding proteins (FCPs)  RSC Advances 15, 4322-4330 (2025).

Supported by Grant agreement ID: 101135402. Project DOI 10.3030/101135402. Project Acronym: Mobiles. Funded by the European Union (Horizon). Views and opinions expressed are however those of the author(s) only and not necessarily reflects those of the European Union or European Research Executive Agency. Neither the European Union nor the European Research Executive Agency can be responsible for them.