The metabolites of light: Untargeted metabolomic approaches bring new clues to understand light-driven acclimation of intertidal mudflat biofilm

Non-enzymatic oxylipin production in a mudflat microphytobenthic biofilm: evidence of a diatom response to light

“…The increase in PhytoPs was observed under 100 and 250 PAR. Under these light conditions, photosynthesis is presumed to be efficient, considering the Ek and Eopt values measured in the same biofilm samples (Doose and Hubas, 2024), and ROS scavengers are likely not overwhelmed. The increase of these oxylipins triggered under an efficient state of photosynthesis might also suggest that the peroxidation could be attributed to ROS originating from non-photosynthetic organisms.…”

“…2, the higher and lower percentages for ALA-derived and EPA-derived oxylipins, respectively, were observed under 250 PAR. Interestingly, the Ek value is situated between 100 and 250 PAR, with 187 ± 22 PAR (Doose and Hubas, 2024). This value is suspected to represent the theoretical optimal light level for the MPB and it was suggested that diatoms adjust through their vertical migration in the sediment the irradiance they receive around this Ek value (Jesus et al, 2023).…”

“…The deepoxydation rate also increased significantly between 250 and 500 PAR, indicating a high NPQ response (Doose and Hubas, 2024). In one hand, NPQ is considered to be the most crucial short-term photoacclimative processes in diatoms (Lavaud, 2007; Lavaud et al, 2002).…”

“…The Biofilm’s sample used to carry this study were the same as those generated after 30 min of light exposure in (Doose and Hubas, 2024). The first 2 cm of sediment present in an empty breeding pond of the Marine Station of Concarneau (France; 47◦52.5804’N; 3◦55.026’W) at low tide was sampled to collect the MPB biofilm.…”