Picoeukaryotic photosynthetic potential is functionally redundant but taxonomically structured at global scale

Alexandre Schickele (1) , Pavla Debeljak (2) , Sakina-Dorothée Ayata (1, 3) , Lucie Bittner (4, 2) , Eric Pelletier (5, 6) , Lionel Guidi (1) , Jean-Olivier Irisson (1)

1 LOV - Laboratoire d'océanographie de Villefranche
2 ISYEB - Institut de Systématique, Evolution, Biodiversité
3 LOCEAN-PROTEO - Processus et interactions de fine échelle océanique
4 IUF - Institut universitaire de France
5 UMR 8030 - Génomique métabolique
6 GOSEE - Global Oceans Systems Ecology & Evolution - Tara Oceans

Abstract Primary production, performed by RUBISCO, and often associated with carbon concentration mechanisms, is of major importance in the oceans. Thanks to growing metagenomic resources (e.g., eukaryotic Metagenome-Assembled-Genomes; MAGs), we provide the first reproducible machine-learning-based framework to derive the potential biogeography of a given function, through the multi-output regression of the standardized number of reads of the associated genes on environmental climatologies. We use it to study the genomic potential of C4-photosynthesis of picoeukaryotes, a diverse and abundant group of marine unicellular photosynthetic organisms. We show that the genomic potential supporting C4-enzymes and RUBISCO exhibit strong functional redundancy and an important affinity towards tropical oligotrophic waters. This redundancy is then structured taxonomically by the dominance of Mamiellophyceae and Prymnesiophyceae in mid and high latitudes. Finally, unlike the genomic potential related to most C4-enzymes, the one of RUBISCO showed a clear pattern affinity for temperate waters.

Domaines: Sciences du Vivant [q-bio]

Alexandre Schickele, Pavla Debeljak, Sakina-Dorothée Ayata, Lucie Bittner, Eric Pelletier, et al.. Picoeukaryotic photosynthetic potential is functionally redundant but taxonomically structured at global scale. 2024. ⟨cea-04321429⟩