Exoenzyme activities associated with sinking diatom aggregates incubated in rotating pressure and control tanks


The effect of increasing hydrostatic pressure on the microbial degradation, the organic matter composition, and the microbiome of 'marine snow' particles was studied in laboratory incubation experiments. Model aggregates were produced from the diatom Skeletonema marinoi and the natural microbial community of surface seawater collected in the Kattegat. The aggregates were incubated individually in rotating pressure and control tanks to keep them suspended during 20-day incubations in the dark and at 3°C. In the pressure tanks, hydrostatic pressure was increased at increments of 5 MPa per day to finally reach 100 MPa. This pressure scheme simulates the descent of diatom aggregates from the surface ocean down into a 10-km deep hadal trench. In the control tanks, pressure was always left at atmospheric level.The activities of 5 exoenzymes (leucine-aminopeptidase, beta-glucosidase, laminarase, pullulanase, chondroitin sulfatase) associated with diatom aggregates were determined using fluorescently labeled substrates. Volumetric exoenzyme activities were calculated from the temporal change in fluorophore concentrations and the individual aggregate volume for samples retrieved every 4-8 days throughout the 20-day incubation experiment.

DOI https://doi.org/10.1594/PANGAEA.960472
Related Identifier https://doi.org/10.1594/PANGAEA.960357
Metadata Access https://ws.pangaea.de/oai/provider?verb=GetRecord&metadataPrefix=datacite4&identifier=oai:pangaea.de:doi:10.1594/PANGAEA.960472
Creator Balmonte, John Paul ORCID logo; Franco-Cisterna, Belén
Publisher PANGAEA
Publication Year 2023
Funding Reference Danish National Research Foundation https://doi.org/10.13039/501100001732 Crossref Funder ID DNRF145 Danish Center for Hadal Research, HADAL
Rights Data access is restricted (moratorium, sensitive data, license constraints)
OpenAccess false
Resource Type Dataset
Format text/tab-separated-values
Size 114 data points
Discipline Earth System Research
Spatial Coverage (10.427 LON, 55.368 LAT)
Temporal Coverage Begin 2021-07-27T13:48:26Z
Temporal Coverage End 2022-11-02T08:27:14Z