GNPSapplication/xmlftp://massive-ftp.ucsd.edu/v07/MSV000094172/primaryOK200MetabolomicsThomas Yon6550 iFunnel Q-TOF LC/MSGambierdiscus Silvae (ncbitaxon:1550089)Gambierdiscus Carolinianus (ncbitaxon:864182)Gambierdiscus Australes (ncbitaxon:439317)Gambierdiscus Belizeanus (ncbitaxon:439316)Gambierdiscus Excentricus (ncbitaxon:986170)Gambierdiscus Caribaeus (ncbitaxon:864185)https://massive.ucsd.edu/ProteoSAFe/dataset.jsp?task=ab8b81b407ce46759e61c9e70b62bdd2Laboratoire METALG, Ifremerthomas.yon@ifremer.frGNPS13MS:1002864 - No post-translational-modifications are included in the identified peptides of this datasetDinoflagellates of the genus Gambierdiscus have been associated with ciguatera, the most common non-bacterial fish-related intoxication in the world. Many studies report the presence of potentially toxic Gambierdiscus species along the Atlantic coasts including G. australes, G. silvae and G. excentricus. Estimates of their toxicity, as determined by bio-assays, vary substantially, both between species and strains of the same species. Therefore, there is a need for additional knowledge on the metabolite production of Gambierdiscus species and their variation to better understand species differences. Using liquid chromatography coupled to mass spectrometry, toxin and metabolomic profiles of five species of Gambierdiscus found in the Atlantic Ocean were reported. In addition, a molecular network was constructed aiming at annotating the metabolomes. Results demonstrated that G. excentricus could be discriminated from the other species based solely on the presence of MTX4 and sulfo-gambierones and that the variation in toxin content for a single strain could be up to a factor of two due to different culture conditions between laboratories. While untargeted analyses highlighted a higher variability at the metabolome level, signal correction was applied and supervised multivariate statistics performed on the untargeted data set permitted the selection of 567 features potentially useful as biomarkers for the distinction of G. excentricus, G. caribaeus, G. carolinianus, G. silvae and G. belizeanus. Further studies will be required to validate the use of these biomarkers in discriminating Gambierdiscus species. The study also provided an overview about 17 compound classes present in Gambierdiscus, however, significant improvements in annotation are still required to reach a more comprehensive knowledge of Gambierdiscus' metabolome.Targeted and non-targeted mass spectrometry to explore the chemical diversity of the genus Gambierdiscus in the Atlantic Ocean.Yon Thomas T, Réveillon Damien D, Sibat Manoëlla M, Holland Chris C, Litaker R Wayne RW, Nascimento Silvia M SM, Rossignoli Araceli E AE, Riobó Pilar P, Hess Philipp P, Bertrand Samuel SfalseGNPS - Targeted and non-targeted mass spectrometry to explore the chemical diversity of the genus Gambierdiscus in the Atlantic OceanThe 15 strains of Gambierdiscus were cultivated in four separate laboratories. Each laboratory grew their available strains (see sample metadata) in addition to the G. australes strain AUS S080911_1 isolated from Pacific Ocean. Irradiance (70-100 umol photons m-2 s-1) and light/dark cycle (12h:12h) were standardized between the different laboratories, the other cultivation parameters were defined by each laboratory considering optimal growth parameters and technical requirements. Samples were extracted twice in methanol 90% from freeze-dried cell pellets (2mL per million of cells). The extraction cycle was as follows: vortex 30 s, ultrasonic bath (25 kHz on ice, 15 min), vortex 30 s and centrifugation (4 000 g, 2 min). The extracts resulting from the two extraction cycles were pooled into an amber glass vial and stored at -80 C (final concentration : 250,000 cells mL-1). Metabolomic profiles were acquired by Ultra-high-performance Liquid Chromatography-High Resolution Mass Spectrometry (UHPLC-HRMS). The instrumentation consisted of a UHPLC system (1290 Infinity II, Agilent) coupled to a quadrupole-time of flight mass spectrometer (QTOF 6550, Agilent) equipped with a Dual Jet Stream electrospray ionization (ESI) interface. The analytical column was a core-shell Kinetex C18 (100 x 2.1 mm, 1.7 um, Phenomenex) with a suited guard column. Mobile phases consisted of water (A) and acetonitrile/water (95:5, V:V) (B), both containing 2 mM ammonium formate and 50 mM formic acid The flow rate was 0.4 mL min-1 and the injection volume was 5 uL. The following elution gradient was used: 5% B (0-1 min), 5-100% B (1-11 min), 100% B (11-13 min), 5% B (13-18 min). Mass spectra were recorded in both positive and negative full-scan modes from m/z 100 to 1700 at a mass resolving power of 25 000 full-width at half-maximum (fwhm, m/z = 922.0099) and an acquisition rate of 2 spectra/s. Auto-MS/MS was performed iteratively: each sample was injected 5 times in ESI+ mode and the ions fragmented were manually excluded from the following analyses Mon Feb 26 10:31:00 GMT 2024MSV00009417238631521