FN Archimer Export Format PT C TI Preliminary metabolomic approach on the bacterial structure community of Haslea ostrearia BT AF MONDEGUER, Florence Lepinay, Alexandra Capiaux, Hervé TURPIN, Vincent Lebeau, Thierry AS 1:1;2:2,3;3:4;4:2;5:3; FF 1:PDG-ODE-DYNECO-PHYC;2:;3:;4:;5:; C1 Ifremer, Laboratoire Phycotoxines, 44311 Nantes Cedex3, France MMS EA 2160, Faculté Sciences et Techniques, Université de Nantes - 44322 Nantes Cedex, France UMR LPGN 6112 CNRS, Université de Nantes - 44322 Nantes Cedex, France Plateforme d'Analyse Moléculaire Biodiversité-Environnement- 85035 La Roche sur Yon, France C2 IFREMER, FRANCE UNIV NANTES, FRANCE UNIV NANTES, FRANCE UNIV NANTES, FRANCE SI NANTES SE PDG-ODE-DYNECO-PHYC UR https://archimer.ifremer.fr/doc/00342/45368/44863.pdf LA English DT Poster DE ;Haslea ostrearia;marine diatom;co-culture microalgae;bacterial community;TTGE;High Resolution Mass Spectrometry;untargeted metabolomics AB The marine diatom Haslea ostrearia [1] produces a water-soluble blue-pigment named marennine [2] of economic interest. But the lack of knowledge of the ecological conditions, under which this microalga develops in its natural ecosystem, more especially bacteria H. ostrearia interactions, prevents any optimization of its culture in well-controlled conditions. The structure of the bacterial community was analyzed by PCR-TTGE before and after the isolation of H. ostrearia cells recovered from 4 localities, to distinguish the relative part of the biotope and the biocenose and eventually to describe the temporal dynamic of the structure of the bacterial community at two time-scales. The differences in genetic fingerprints, more especially high between two H. ostrearia isolates (HO-R and HO-BM) showed also the highest differences in the bacterial structure [3] as the result of specific metabolomics profiles. The non-targeted metabolomic investigation showed that these profiles were more distinct in case of bacteria-alga associations than for the H. ostrearia monoculture Here we present a Q-TOF LC/MS metabolomic fingerprinting approach [3]: - to investigate differential metabolites of axenic versus non axenic H. ostrearia cultures. - to focus on the specific metabolites of a bacterial surrounding associated with the activation or inhibition of the microalga growing. The Agilent suite of data processing software makes feature finding, statistical analysis, and identification easier. This enables rapid transformation of complex raw data into biologically relevant metabolite information. PY 2016 PD MAY ID 45368 ER EF