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Coscinodiscus Synthetic Community

Community ID CommunityMech:000020
Ecological State ENGINEERED
Environment marine environment
ENVO:01000320 · HabitatMech ↗

A synthetic marine phytoplankton community consisting of the large centric diatom Coscinodiscus radiatus and four phylogenetically distinct bacterial isolates from different marine bacterial lineages. This model system was established to examine species-specific diatom-bacteria interactions and community dynamics. The bacteria include two Roseobacteraceae members (Mameliella CS4 and Roseovarius Rose1), a gammaproteobacterium (Marinobacter CS1), and a Flavobacterium (Croceibacter Crocei1). The consortium demonstrates context-dependent bacterial effects on diatom growth that vary with algal fitness state, growth phase, and community composition, with no universal algicidal or growth-promoting bacteria observed. This system is relevant to understanding carbon cycling and primary production in marine ecosystems.

Taxonomy

Taxon Ontology ID Functional Roles Abundance
Coscinodiscus radiatus NCBITaxon:33642 · TaxonMech · TraitMech
PRIMARY_PRODUCER
DOMINANT
  • PMID:36300970 - SUPPORT (IN_VITRO)
    "We further established a synthetic phytoplankton/bacteria community with the centric diatom, Coscinodiscus radiatus, and 4 phylogenetically distinctive bacterial isolates, Mameliella sp., Roseovarius sp., Croceibacter sp., and Marinobacter sp. Supported by a Lotka-Volterra model, we show that interactions within the consortium are specific and that the sum of the pairwise interactions can explain algal and bacterial growth in the community"
Mameliella CS4 — ontology label: Mameliella NCBITaxon:1434019 · TaxonMech · TraitMech
SYNTROPHIC_PARTNER
ABUNDANT
  • PMID:36300970 - SUPPORT (IN_VITRO)
    "We further established a synthetic phytoplankton/bacteria community with the centric diatom, Coscinodiscus radiatus, and 4 phylogenetically distinctive bacterial isolates, Mameliella sp., Roseovarius sp., Croceibacter sp., and Marinobacter sp. Supported by a Lotka-Volterra model, we show that interactions within the consortium are specific and that the sum of the pairwise interactions can explain algal and bacterial growth in the community"
Roseovarius Rose1 — ontology label: Roseovarius NCBITaxon:74030 · TaxonMech · TraitMech
SYNTROPHIC_PARTNER
ABUNDANT
  • PMID:36300970 - SUPPORT (IN_VITRO)
    "We further established a synthetic phytoplankton/bacteria community with the centric diatom, Coscinodiscus radiatus, and 4 phylogenetically distinctive bacterial isolates, Mameliella sp., Roseovarius sp., Croceibacter sp., and Marinobacter sp. Supported by a Lotka-Volterra model, we show that interactions within the consortium are specific and that the sum of the pairwise interactions can explain algal and bacterial growth in the community"
Croceibacter Crocei1 — ontology label: Croceibacter NCBITaxon:216431 · TaxonMech · TraitMech
SYNTROPHIC_PARTNER
ABUNDANT
  • PMID:36300970 - SUPPORT (IN_VITRO)
    "We further established a synthetic phytoplankton/bacteria community with the centric diatom, Coscinodiscus radiatus, and 4 phylogenetically distinctive bacterial isolates, Mameliella sp., Roseovarius sp., Croceibacter sp., and Marinobacter sp. Supported by a Lotka-Volterra model, we show that interactions within the consortium are specific and that the sum of the pairwise interactions can explain algal and bacterial growth in the community"
Marinobacter CS1 — ontology label: Marinobacter NCBITaxon:2742 · TaxonMech · TraitMech
SYNTROPHIC_PARTNER
ABUNDANT
  • PMID:36300970 - SUPPORT (IN_VITRO)
    "We further established a synthetic phytoplankton/bacteria community with the centric diatom, Coscinodiscus radiatus, and 4 phylogenetically distinctive bacterial isolates, Mameliella sp., Roseovarius sp., Croceibacter sp., and Marinobacter sp. Supported by a Lotka-Volterra model, we show that interactions within the consortium are specific and that the sum of the pairwise interactions can explain algal and bacterial growth in the community"

Ecological Interactions

The graph shows only explicitly linked interaction participants. Community members without an asserted participant link are omitted; membership alone does not imply an interaction.

Ecological interaction network for Coscinodiscus Synthetic Community Bipartite graph where circles represent taxa and non-circular symbols represent interactions. Rare or untyped interactions share the Other symbol; exact curated types remain in the interaction details.
Taxon
Other

Candidate Diatom Resource Provision

The phototrophic diatom is a candidate supplier of bacterial resources. Coculture increased Crocei1 abundance, but did not significantly increase CS4 or Rose1 and inhibited CS1 after day 9. Thus diatom presence has partner-specific effects; neither universal bacterial dependence nor direct release and transfer of DMSP, amino acids or vitamins was established. Photosynthetic resource provision is a proposed mediator rather than a measured metabolite flux.

Source Taxon: Coscinodiscus radiatus

Metabolites: dimethylsulfoniopropionate (CHEBI:16457 · MediaIngredientMech · CMMMech), amino acids (CHEBI:33709 · MediaIngredientMech · CMMMech), vitamins (CHEBI:33229 · MediaIngredientMech · CMMMech)

Biological Processes:

Downstream Effects:
→ Bacterial DMSP Catabolic Potential

HYPOTHESIZED - diatom-derived DMSP could provide substrate for the genomic catabolic potential of CS4 and Rose1. No partner-resolved release, consumption or flux was measured, and added DMSP as the carbon-only supplement did not promote growth under the tested minimal-medium conditions.

Evidence

  • PMID:36300970 - PARTIAL (IN_VITRO)
    "Crocei1 grew to significantly higher density"

Bacterial DMSP Catabolic Potential

BLASTP comparisons of predicted bacterial proteins support DMSP demethylation/cleavage potential in CS4 and Rose1. Crocei1 had weak homologs and CS1 lacked the key DmdA sequence, although downstream homologs suggest possible MMPA use. This is sequence-based potential, not measured DMSP consumption, DMS release or diatom-to-bacterium flux. DMSP carbon-only supplementation did not promote growth; that negative growth result does not itself prove absence of catabolic activity.

Participating Taxa: Mameliella CS4, Roseovarius Rose1

Metabolites: dimethylsulfoniopropionate (CHEBI:16457 · MediaIngredientMech · CMMMech), dimethyl sulfide (CHEBI:17437 · MediaIngredientMech · CMMMech)

Biological Processes:

Evidence

  • PMID:36300970 - PARTIAL (COMPUTATIONAL)
    "potential for DMSP consumption"

Growth Phase-Dependent Bacterial Effects

In pairwise cultures, CS4 and Rose1 prolonged algal stationary-phase survival; Crocei1 inhibited the diatom across phases. CS1 initially suppressed algal growth, followed by recovery to control-like density after day 9, not necessarily growth above control. Reciprocal bacterial responses differed: Crocei1 benefited, CS1 was inhibited significantly on days 11-21, and CS4/Rose1 showed no significant diatom effect. These measured responses do not support one global mutualism label or identify their chemical mediators.

Participating Taxa: Coscinodiscus radiatus, Mameliella CS4, Roseovarius Rose1, Croceibacter Crocei1, Marinobacter CS1

Biological Processes:

Downstream Effects:
→ Community Growth and Pairwise Model

PARTIAL - the measured partner- and phase-specific effects combine into the observed predominantly inhibitory all-member algal trajectory. A generalized Lotka-Volterra model fitted to monocultures and pairwise cultures reproduces that trajectory with separate early/late parameter sets; this supports the proposed contribution without isolating chemical mediators or proving higher-order interactions universally absent.

Evidence

  • PMID:36300970 - SUPPORT (IN_VITRO)
    "The activity of bacteria can even change during the aging of an algal culture from inhibitory to stimulatory or vice versa"

Bacterial Nutrient Supplement Responses

Minimal-medium supplementation with a pooled 13-amino-acid mixture plus vitamins improved growth of Rose1, Crocei1 and CS1; CS4 did not respond. DMSP or glucose supplied as carbon alone did not promote any of the four bacteria. These are direct nutrient-response assays, not merely genomic predictions. Genome analysis separately predicted amino-acid deficits, Rose1 niacin deficiency and Crocei1/CS1 vitamin B12 biosynthesis deficits. The pooled rescue does not establish which individual nutrient was limiting, its exact B12 chemical form, or donation by the diatom.

Participating Taxa: Roseovarius Rose1, Croceibacter Crocei1, Marinobacter CS1

Metabolites: amino acids (CHEBI:33709 · MediaIngredientMech · CMMMech), vitamins (CHEBI:33229 · MediaIngredientMech · CMMMech)

Biological Processes:

Evidence

  • PMID:36300970 - SUPPORT (IN_VITRO)
    "all other bacteria grew better"

Community Growth and Pairwise Model

The all-member culture generally had lower algal cell counts than the axenic control, especially before day 17; the paper also describes a very-late survival benefit. Bacteria performed similarly or slightly better than in mono/pairwise cultures, so this is not reciprocal competitive harm. A generalized Lotka-Volterra model fitted to mono/pairwise data with distinct days 1-17 and 17-41 parameter sets predicted the algal community trajectory; a neutral model failed. Bacterial-bacterial terms were unnecessary for this tested fit, not proven universally absent, and chemical cross-feeding was not thereby established.

Participating Taxa: Coscinodiscus radiatus, Mameliella CS4, Roseovarius Rose1, Croceibacter Crocei1, Marinobacter CS1

Biological Processes:

Evidence

  • PMID:36300970 - SUPPORT (IN_VITRO)
    "No synergistic effects between bacteria in the presence of the diatom was observed"

Knowledge gaps & discussions (1)

KNOWLEDGE_GAP OPEN Which exchanged compounds mediate the partner- and phase-specific growth responses?

Complete primary main text, tables and captions support pairwise growth, pooled nutrient supplementation and a phase-specific community model. Direct DMSP release/consumption flux, individual nutrient rescue and mediator-specific perturbations remain unresolved; carbon-only supplementation was negative. CS4 is a nonresponding supplementation control despite predicted deficits. Prior rich-medium stores may buffer responses. The model fit does not rule out interactions under other nutrient conditions. The publisher-provided preview was read without copying its copyrighted body; three brief Results excerpts remain a documented abstract-cache retrieval gap under #596. No figure images or supplementary files were inspected. Non-graph roles, cultivation parameters and source discrepancies remain in #1359.

Attaches to: ecological_interactions#Candidate Diatom Resource Provision, ecological_interactions#Bacterial DMSP Catabolic Potential, ecological_interactions#Growth Phase-Dependent Bacterial Effects, ecological_interactions#Bacterial Nutrient Supplement Responses, ecological_interactions#Community Growth and Pairwise Model

Environmental Factors

Factor Value Unit
Marine medium Artificial seawater medium N/A
  • PMID:36300970 - SUPPORT (IN_VITRO)
    "We further established a synthetic phytoplankton/bacteria community with the centric diatom, Coscinodiscus radiatus, and 4 phylogenetically distinctive bacterial isolates, Mameliella sp., Roseovarius sp., Croceibacter sp., and Marinobacter sp. Supported by a Lotka-Volterra model, we show that interactions within the consortium are specific and that the sum of the pairwise interactions can explain algal and bacterial growth in the community"
Light Illuminated culture conditions N/A
  • PMID:36300970 - SUPPORT (IN_VITRO)
    "We further established a synthetic phytoplankton/bacteria community with the centric diatom, Coscinodiscus radiatus, and 4 phylogenetically distinctive bacterial isolates, Mameliella sp., Roseovarius sp., Croceibacter sp., and Marinobacter sp. Supported by a Lotka-Volterra model, we show that interactions within the consortium are specific and that the sum of the pairwise interactions can explain algal and bacterial growth in the community"
Growth phase Dynamic across growth phases N/A
  • PMID:36300970 - SUPPORT (IN_VITRO)
    "Bacteria utilize substrates produced by the phototrophic algae, while algal growth can be supported by bacterial exudates"
Nutrient availability Varied nutrient conditions N/A
  • PMID:36300970 - SUPPORT (IN_VITRO)
    "We further established a synthetic phytoplankton/bacteria community with the centric diatom, Coscinodiscus radiatus, and 4 phylogenetically distinctive bacterial isolates, Mameliella sp., Roseovarius sp., Croceibacter sp., and Marinobacter sp. Supported by a Lotka-Volterra model, we show that interactions within the consortium are specific and that the sum of the pairwise interactions can explain algal and bacterial growth in the community"

Growth Media

f/2 medium with silicate for marine diatom cultivation (CultureMech:000149)

View in CultureMech →

pH 8.0
Temperature 18 degrees Celsius
Atmosphere AEROBIC

Composition

Component Concentration Unit CHEBI
Sodium nitrate (nitrogen source) · MediaIngredientMech 75 mg/L CHEBI:63005
Sodium phosphate monobasic (phosphorus source) · MediaIngredientMech 5 mg/L CHEBI:37585
Sodium metasilicate (silicate for diatom frustules) · MediaIngredientMech 30 mg/L CHEBI:60720
Iron (as FeCl3 in EDTA) · MediaIngredientMech 3.15 mg/L CHEBI:30808
EDTA (chelating agent) · MediaIngredientMech 4.36 mg/L CHEBI:42191
Manganese chloride · MediaIngredientMech 0.18 mg/L CHEBI:63041
Zinc sulfate · MediaIngredientMech 0.022 mg/L CHEBI:35176
Cobalt chloride · MediaIngredientMech 0.01 mg/L CHEBI:35696
Copper sulfate · MediaIngredientMech 0.01 mg/L CHEBI:23414
Sodium molybdate · MediaIngredientMech 0.006 mg/L CHEBI:75213
Vitamin B12 (cyanocobalamin) · MediaIngredientMech 0.0005 mg/L CHEBI:15982
Biotin (Vitamin B7) · MediaIngredientMech 0.0005 mg/L CHEBI:57586
Thiamine HCl (Vitamin B1) · MediaIngredientMech 0.1 mg/L CHEBI:18385
See source for composition · MediaIngredientMech variable VARIABLE N/A

Preparation notes: f/2 medium (Guillard and Ryther 1962, Guillard 1975) is the standard growth medium for marine diatoms and phytoplankton. The medium is prepared with filtered natural seawater or artificial seawater (30 ppt salinity) enriched with f/2 nutrients, trace metals, and vitamins. Silicate (sodium metasilicate) is essential for diatom growth as it is required to build the biomineralized silica frustule cell wall. Autoclaved f/2 medium may produce silica precipitate. The medium supports both photosynthetic diatom growth and heterotrophic bacterial growth on diatom-derived organic compounds.

Evidence

PMID:36300970

"We further established a synthetic phytoplankton/bacteria community with the centric diatom, Coscinodiscus radiatus, and 4 phylogenetically distinctive bacterial isolates, Mameliella sp., Roseovarius sp., Croceibacter sp., and Marinobacter sp. Supported by a Lotka-Volterra model, we show that interactions within the consortium are specific and that the sum of the pairwise interactions can explain algal and bacterial growth in the community"

Cross-Mech Suite Links

Explore related entities across the CultureBotAI X-Mech knowledge bases:

HabitatMech: marine environment ↗ TaxonMech: Coscinodiscus radiatus ↗ TraitMech: Coscinodiscus radiatus ↗ TaxonMech: Mameliella CS4 ↗ TraitMech: Mameliella CS4 ↗ TaxonMech: Roseovarius Rose1 ↗ TraitMech: Roseovarius Rose1 ↗ TaxonMech: Croceibacter Crocei1 ↗ TraitMech: Croceibacter Crocei1 ↗ TaxonMech: Marinobacter CS1 ↗ TraitMech: Marinobacter CS1 ↗ CultureMech Growth Media ↗ PathwayMech Pathways ↗