TY - JOUR T1 - Microbial iron metabolism as revealed by gene expression profiles in contrasted Southern Ocean regimes A1 - Debeljak,Pavla A1 - Toulza,Eve A1 - Beier,Sara A1 - Blain,Stephane A1 - Obernosterer,Ingrid AD - Sorbonne Université, CNRS, Laboratoire d'Océanographie Microbienne, LOMIC F‐66650 Banyuls/mer ,France AD - Department of Limnology and Bio‐OceanographyUniversity of Vienna A‐1090 Vienna ,Austria AD - Université Perpignan Via Domitia, IHPE UMR 5244, CNRS, IFREMER, Univ. Montpellier F‐66860 Perpignan ,France AD - Leibniz Institute for Baltic Sea Research Warnemünde, Germany UR - https://archimer.ifremer.fr/doc/00488/59921/ DO - 10.1111/1462-2920.14621 N2 - Iron (Fe) is a limiting nutrient in large regions of the ocean, but the strategies of prokaryotes to cope with this micronutrient are poorly known. Using a gene‐specific approach from metatranscriptomics data, we investigated 7 Fe‐related metabolic pathways in microbial communities from High Nutrient Low Chlorophyll and naturally Fe‐fertilized waters in the Southern Ocean. We observed major differences in the contribution of prokaryotic groups at different taxonomic levels to transcripts encoding Fe uptake‐mechanisms, intracellular Fe storage and replacement, and Fe‐related pathways in the tricarboxylic acid (TCA) cycle. The composition of the prokaryotic communities contributing to the transcripts of a given Fe‐related pathway was overall independent of the in situ Fe supply, indicating that microbial taxa utilize distinct Fe‐related metabolic processes. Only a few prokaryotic groups contributed to the transcripts of more than one Fe‐uptake mechanism, suggesting limited metabolic versatility. Taxa‐specific expression of individual genes varied among prokaryotic groups and was substantially higher for all inspected genes in Fe‐limited as compared to naturally fertilized waters, indicating the link between transcriptional state and Fe regime. Different metabolic strategies regarding low Fe concentrations in the Southern Ocean are discussed for two abundant prokaryotic groups, Pelagibacteraceae and Flavobacteriaceae. Y1 - 2019/07 PB - Wiley JF - Environmental Microbiology SN - 1462-2912 VL - 21 IS - 7 SP - 2360 EP - 2374 ID - 59921 ER -