10.1594/PANGAEA.974879Stief, PeterPeterStief0000-0002-6355-150XDanish Center for Hadal ResearchPANGAEA2025culture experimentdiatomsDOMDOM degradationhydrostatic pressureLaboratory experimentleakagemicrobial communityseawaterType of studyDate/time start, experimentDate/time end, experimentSpecies, unique identificationTreatment: carbonTreatment: durationCarbon, organic, dissolvedNitrogen, total dissolvedProteins, totalPolysaccharidesBacteriaRespiration rate, oxygenCTD/RosetteTotal organic carbon analyzer, Shimadzu, TOC-LLowry assay after Lowry et al. 1951PAHBAH reducing sugar assay (Lever 1972)Fluorescence determination of DAPI stainOxygen logger, FireSting, Pyroscience2019-04-07T12:00:00/2019-04-07T13:00:00Dataset10.1038/s43247-023-01045-41424 data pointstext/tab-separated-valuesCreative Commons Attribution 4.0 InternationalStored surface seawater originally collected in the North Sea was amended with dissolved organic matter (DOM) obtained from the diatom Skeletonema marinoi by exposing the diatom culture to a hydrostatic pressure level of 40 MPa for 24 h. To this end, S. marinoi had been grown to stationary phase in L1 medium plus silicate (Guillard & Hargraves 1993) at 15°C under a light/dark regime of 14/10 h. Diatom-cell-free DOM was added to aliquoted seawater samples at initial concentrations of 250 µmol C/L. The microbial degradation of the added DOM and the microbial response to DOM-amendment at 15°C and in darkness was followed for 2 weeks. The seawater was subsampled at defined time intervals to analyze a number of variables.Information about the used cultured organisms:
Skeletonema marinoi, Bigelow National Center for Marine Algae and Microbiota, Strain No. CCMP1332, isolated from Long Island Sound (41.2264 N, -73.0639 W) (isolation date is unknown); https://ncma.bigelow.org/CCMP13327.84154.155Danish National Research Foundationhttps://doi.org/10.13039/501100001732DNRF145Danish Center for Hadal Research, HADAL