cover image: Microscale imaging sheds light on species‐specific strategies for photo‐regulation and photo‐acclimation of microphytobenthic diatoms

Microscale imaging sheds light on species‐specific strategies for photo‐regulation and photo‐acclimation of microphytobenthic diatoms

6 Sep 2023

Intertidal microphytobenthic (MPB) biofilms are key sites for coastal primary production, predominantly by pennate diatoms exhibiting photo-regulation via non-photochemical quenching (NPQ) and vertical migration. Movement is the main photo-regulation mechanism of motile (epipelic) diatoms and because they can move from light, they show low-light acclimation features such as low NPQ levels, as compared to non-motile (epipsammic) forms. However, most comparisons of MPB species-specific photo-regulation have used low light acclimated monocultures, not mimicking environmental conditions. Here we used variable chlorophyll fluorescence imaging, fluorescent labelling in sediment cores and scanning electron microscopy to compare the movement and NPQ responses to light of four epipelic diatom species from a natural MPB biofilm. The diatoms exhibited different species-specific photo-regulation features and a large NPQ range, exceeding that reported for epipsammic diatoms. This could allow epipelic species to coexist in compacted light niches of MPB communities. We show that diatom cell orientation within MPB can be modulated by light, where diatoms oriented themselves more perpendicular to the sediment surface under high light vs. more parallel under low light, demonstrating behavioural, photo-regulatory response by varying their light absorption cross-section. This highlights the importance of considering species-specific responses and understanding cell orientation and photo-behaviour in MPB research.

Authors

Bruno Jesus, Thierry Jauffrais, Erik Trampe, Vona Méléder, Lourenço Ribeiro, Joan M Bernhard, Emmanuelle Geslin, Michael Kühl

Mentioned Organizations

European Union
Institut National des Sciences de l'Univers
Bibliographic Reference
Bruno Jesus, Thierry Jauffrais, Erik Trampe, Vona Méléder, Lourenço Ribeiro, et al.. Microscale imaging sheds light on species‐specific strategies for photo‐regulation and photo‐acclimation of microphytobenthic diatoms. Environmental Microbiology, 2023, ⟨10.1111/1462-2920.16499⟩. ⟨hal-04240824⟩
DOI
https://doi.org/10.1111/1462-2920.16499
European Project Title
Marie Sklodowska-Curie Research and Innovation Staff Exchange
Funding
Region Pays de Loire, Grant/Award Number: University of Angers(France); WHOI’s Investment in ScienceProgram
HAL Collection
['IRD - Institut de recherche pour le développement', "Sciences De l'Environnement", "INSU - Institut National des Sciences de l'Univers", 'CNRS - Centre national de la recherche scientifique', "Université d'Angers", 'Université du Mans', 'Université de Nouvelle Calédonie', "IFREMER : Institut français de recherche pour l'exploitation de la mer", 'OpenAIRE', 'GIP Bretagne Environnement', 'Université de la Nouvelle-Calédonie', 'Institut Des Substances et Organismes de la Mer', 'Nantes Université', 'Presses Universitaires de la Nouvelle-Calédonie', 'LARJE (PUNC)', 'LA-NI (PUNC)', 'CRESICA (PUNC)', 'LIRE (PUNC)', 'RESONANCES (PUNC)']
HAL Identifier
4240824
Institution
['Nantes Université - pôle Santé', 'Nantes Université - pôle Sciences et technologie', 'Institut de Recherche pour le Développement', "Institut Français de Recherche pour l'Exploitation de la Mer", 'Université de la Nouvelle-Calédonie', 'University of Copenhagen = Københavns Universitet', 'Faculdade de Ciencias da Universidade de Lisboa', 'Woods Hole Oceanographic Institution', 'Le Mans Université', "Université d'Angers", "Institut national des sciences de l'Univers"]
Laboratory
['Institut Des Substances et Organismes de la Mer - UR 2160', 'Ecologie marine tropicale des océans Pacifique et Indien', 'Marine and Environmental Sciences Centre', 'Laboratoire de Planétologie et Géosciences [UMR_C 6112]']
Published in
France

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