← Back to Communities

Thalassiosira-Marinobacter Marine Snow Coculture

Community ID CommunityMech:000259
Ecological State ENGINEERED
Environment laboratory marine phycosphere coculture
ENVO:01001405

A defined marine diatom-bacterium coculture pairing the centric diatom Thalassiosira weissflogii, currently represented in NCBI Taxonomy as Conticribra weissflogii, with the diatom-attaching heterotrophic bacterium Marinobacter adhaerens HP15. The system is used to study phycosphere attachment, transparent exopolymer particle formation, aggregate formation, and sinking-particle processes relevant to the marine biological carbon pump. Multiple publications use the same exact diatom-bacterium model, including studies of aggregation requirements, chemotaxis-mediated attachment, and temperature/pCO2 perturbations.

Taxonomy

Taxon Ontology ID Functional Roles Abundance
Thalassiosira weissflogii NCBITaxon:1577725
PRIMARY_PRODUCER CROSS_FEEDER
N/A
  • PMID:20827289 - SUPPORT (IN_VITRO)
    "Thalassiosira weissflogii might interact"
Marinobacter adhaerens HP15 NCBITaxon:225937
CROSS_FEEDER
N/A
  • PMID:22820333 - SUPPORT (IN_VITRO)
    "Marinobacter adhaerens HP15 has been demonstrated to attach to the diatom Thalassiosira weissflogii"

Ecological Interactions

Ecological interaction network for Thalassiosira-Marinobacter Marine Snow Coculture Bipartite graph where circle nodes represent taxa and colored rectangles represent ecological interactions (cross-feeding, mutualism, syntrophy, competition, commensalism).
Taxon
Cross-feeding
Mutualism
Syntrophy
Competition
Commensalism
Niche partitioning
Colonization facilitation
Strain competition
Predation

Bacteria-Dependent Diatom Aggregation

COLONIZATION_FACILITATION

Source Taxon: Marinobacter adhaerens HP15

Target Taxon: Thalassiosira weissflogii

Biological Processes:

  • biological process involved in interspecies interaction between organisms (GO:0044419)
  • biofilm formation (GO:0042710)

Evidence

  • PMID:20827289 - SUPPORT (IN_VITRO)
    "specific diatom-attaching bacteria were required for aggregation"
  • PMID:20827289 - SUPPORT (IN_VITRO)
    "T. weissflogii did not aggregate in axenic culture"
  • doi:10.4056/sigs.922139 - SUPPORT (IN_VITRO)
    "it showed specific attachment to diatom cells. In vitro it led to exopolymer formation and aggregation of these algal cells to form marine snow particles"

Transparent Exopolymer Particle Enhancement

CROSS_FEEDING

Source Taxon: Thalassiosira weissflogii

Target Taxon: Marinobacter adhaerens HP15

Biological Processes:

Evidence

  • PMID:22820333 - SUPPORT (IN_VITRO)
    "induce transparent exopolymeric particle and aggregate formation"
  • PMID:20827289 - SUPPORT (IN_VITRO)
    "TEP formation and phytoplankton aggregation"
  • doi:10.3354/meps09894 - PARTIAL (IN_VITRO)
    "a co-incubation sample containing the diatom Thalassiosira weissflogii (left) and Marinobacter adhaerens HP15 embedded in a network of chitincontaining fibres extruding from the diatom cell"

Chemotaxis-Mediated Attachment

COLONIZATION_FACILITATION

Source Taxon: Marinobacter adhaerens HP15

Target Taxon: Thalassiosira weissflogii

Biological Processes:

Evidence

  • PMID:22820333 - SUPPORT (IN_VITRO)
    "chemotaxis might be important for the interaction of M. adhaerens with diatoms"
  • PMID:22820333 - SUPPORT (IN_VITRO)
    "the fraction of bacteria attaching to the diatom decreased significantly for mutants"

Marine Snow Carbon Flux Model

NICHE_PARTITIONING

Metabolites: carbon dioxide (CHEBI:16526)

Biological Processes:

  • photosynthesis (GO:0015979)
  • biological process involved in interspecies interaction between organisms (GO:0044419)

Evidence

  • PMID:20827289 - SUPPORT (IN_VITRO)
    "may enhance the efficiency of the biological pump"
  • PMID:25375640 - SUPPORT (IN_VITRO)
    "potentially reduced carbon sequestration after diatom blooms"

Associated Datasets

Dataset Type Repository Accession
Exact-composition publication - diatom aggregation requirement
Primary study showing that photosynthetically active T. weissflogii and specific diatom-attaching bacteria, including HP15, were required for aggregation. 		PHENOTYPE OTHER PMID:20827289
Exact-composition publication - chemotaxis and attachment
Exact-system mechanistic study testing M. adhaerens chemotaxis and attachment to T. weissflogii cells and TEP aggregates. 		PHENOTYPE OTHER PMID:22820333
Exact-composition publication - future-ocean aggregation perturbation
Exact-system study of T. weissflogii aggregation and sedimentation with or without M. adhaerens HP15 under temperature and pCO2 scenarios. 		PHENOTYPE OTHER PMID:25375640

Environmental Factors

Factor Value Unit
Photosynthetic activity photosynthetically active versus inactivated diatom cells N/A
  • PMID:20827289 - SUPPORT (IN_VITRO)
    "photosynthetically inactivated T. weissflogii cells did not aggregate"
Temperature and pCO2 two temperature and three pCO2 scenarios N/A
  • PMID:25375640 - SUPPORT (IN_VITRO)
    "under two temperature and three pCO2 scenarios"

Growth Media

Marine diatom-bacterium aggregation assay

Atmosphere AEROBIC

Preparation notes: Controlled marine laboratory cocultures of T. weissflogii with M. adhaerens HP15 were incubated in aggregation and exudation assays. Detailed medium recipes are not asserted beyond the source-supported marine coculture context.

Evidence

PMID:20827289

"investigated in vitro"