“…Despite the differences in the environmental setting among stations (Table S1, Lasbleiz et al, 2016) the contribution of SAR11 to the total cells and to active cells appeared to be relatively constant. This is likely due to their successful adaptation to oligotrophic waters and to their capacity to efficiently take up organic substrates, among those some phytoplankton‐derived metabolites, such as very labile volatile molecules (Moore et al, 2020, 2022; Sun et al, 2011), while other taxa may favour high‐molecular‐weight DOM utilization (Malmstrom et al, 2005) as reported during the present cruise (Fourquez et al, 2016; Landa et al, 2018). So far, no known siderophores or heme uptake genes have been observed in SAR11 genomes (Hogle et al, 2016), suggesting that the success of SAR11 in these Fe‐limited waters could further be due to other specific strategies related to uptake, storage and utilization of this limiting micronutrient (Beier et al, 2015; Debeljak et al, 2019; Sun et al, 2021).…”