FN Archimer Export Format PT J TI Use of a lipid rich strain reveals mechanisms of nitrogen limitation and carbon partitioning in the haptophyte Tisochrysis lutea BT AF GARNIER, Matthieu BOUGARAN, Gael PAVLOVIC, Marija BERARD, Jean-Baptiste CARRIER, Gregory CHARRIER, Aurelie LE GRAND, Fabienne LUKOMSKA, Ewa ROUXEL, Catherine SCHREIBER, Nathalie CADORET, Jean-Paul ROGNIAUX, Helene SAINT-JEAN, Bruno AS 1:1;2:1;3:2;4:1;5:1;6:1;7:3;8:1;9:1;10:1;11:1;12:2;13:1; FF 1:PDG-RBE-BRM-PBA;2:PDG-RBE-BRM-PBA;3:;4:PDG-RBE-BRM-PBA;5:PDG-RBE-BRM-PBA;6:PDG-RBE-BRM-PBA;7:;8:PDG-RBE-BRM-PBA;9:PDG-RBE-BRM-PBA;10:PDG-RBE-BRM-PBA;11:PDG-RBE-BRM;12:;13:PDG-RBE-BRM-PBA; C1 IFREMER, PBA, Rue Ile Yeu,BP 21105, F-44311 Nantes 03, France. INRA, UR1268, BIA, Rue Geraudiere,BP71627, F-44313 Nantes 03, France. Univ Brest, CNRS, IFREMER, IRD,LEMAR,IUEM, Pl Nicolas Copernic, F-29280 Plouzane, France. C2 IFREMER, FRANCE INRA, FRANCE CNRS, FRANCE SI NANTES SE PDG-RBE-BRM-PBA PDG-RBE-BRM UM LEMAR IN WOS Ifremer jusqu'en 2018 copubli-france copubli-p187 IF 3.994 TC 23 UR https://archimer.ifremer.fr/doc/00356/46702/46904.pdf LA English DT Article DE ;Algae;Isochrysis;Lipids;Nitrogen;Reverse genomic: proteomic AB Haptophytes are a diverse monophyletic group with a worldwide distribution, known to be significantly involved in global climate regulation in their role as a carbon sink. Because nitrogen is a major limiting macronutrient for phytoplankton in oceans and for cultures of microalgae, understanding the involvement of nitrogen availability in haptophyte carbon partitioning is of global and biotechnological importance. Here, we made an ecophysiological study coupled with comprehensive large scale proteomic analysis to examine differences of behavior in reaction to nitrogen availability changes between a wild type strain of Tisochrysis lutea (WTc1) and a mutant strain (2Xc1) known to accumulate more storage lipids. Strains were grown in chemostats and studied under different ecophysiological conditions including N limitation, N repletion and N depletion. Whereas short time N repletion triggered consumption of carbohydrates in both strains, storage lipid degradation and accumulation during changes of ecophysiological status were recorded in 2Xc1 but not in WTc1. After 3 months of continuous culture, 2Xc1 exhibited an unexpected increase of carbon sequestration ability (+ 50%) by producing twofold more carbohydrates for the same nitrogen availability. Deep proteomic analysis by LC-MS/MS identified and compared the abundance of 4332 proteins, i.e. the deepest coverage of a microalgal proteome obtained to date. Results revealed that storage lipid accumulation is favored by an overall reorganization of carbon partitioning in 2Xc1 cells that increases the metabolism of carbon and energy acquisition, and decreases mitochondrial activity and metabolic conversion of storage lipids to phosphoenolpyruvate before gluconeogenesis. PY 2016 PD DEC SO Algal Research-biomass Biofuels And Bioproducts SN 2211-9264 PU Elsevier Science Bv VL 20 UT 000390560000028 BP 229 EP 248 DI 10.1016/j.algal.2016.10.017 ID 46702 ER EF