Methylomicrobium-Chlorella Methane Sequestration Coculture

Community ID CommunityMech:000192

Ecological State ENGINEERED

Environment saline methane-fed laboratory coculture
ENVO:01001405

A defined halotolerant methanotroph-microalga coculture pairing Methylomicrobium alcaliphilum 20Z, currently represented by NCBI as Methylotuvimicrobium alcaliphilum 20Z, with Chlorella sp. HS2. The two-member system was assembled to test biological methane and carbon dioxide mitigation through metabolic coupling in saline culture, with increased methane removal, improved growth of both members, pH recovery, and greater biomass carbon sequestration reported in coculture. The system is relevant to DOE interests in methane mitigation, carbon capture and utilization, photosynthetic-methanotrophic consortia, and C1 bioconversion.

Taxonomy

Taxon	Ontology ID	Functional Roles	Abundance
Methylomicrobium alcaliphilum 20Z	NCBITaxon:1091494	PRIMARY_DEGRADER CROSS_FEEDER	N/A
doi:10.1016/j.biortech.2024.130607 - SUPPORT (IN_VITRO) "M. alcaliphilum 20Z and Chlorella sp. HS2 were co-cultivated" doi:10.1016/j.biortech.2024.130607 - SUPPORT (IN_VITRO) "Methylomicrobium alcaliphilum 20Z was demonstrated to form a mutualistic association"
Chlorella sp. HS2	NCBITaxon:2675547	PRIMARY_PRODUCER CROSS_FEEDER	N/A
doi:10.1016/j.biortech.2024.130607 - SUPPORT (IN_VITRO) "M. alcaliphilum 20Z and Chlorella sp. HS2 were co-cultivated" doi:10.1016/j.biortech.2024.130607 - SUPPORT (IN_VITRO) "mutualistic association with Chlorella sp. HS2"

Ecological Interactions

Taxon

Cross-feeding

Mutualism

Syntrophy

Competition

Commensalism

Niche partitioning

Colonization facilitation

Strain competition

Predation

Methane Removal and Mutualistic Growth

MUTUALISM

Source Taxon: Chlorella sp. HS2

Target Taxon: Methylomicrobium alcaliphilum 20Z

Metabolites: methane (CHEBI:16183), dioxygen (CHEBI:15379)

Biological Processes:

methane metabolic process (GO:0015947)
photosynthesis (GO:0015979)
biological process involved in interspecies interaction between organisms (GO:0044419)

Evidence

doi:10.1016/j.biortech.2024.130607 - SUPPORT (IN_VITRO)

"Increased CH4 removal and growth of both microbes were observed in co-cultures."
doi:10.1016/j.biortech.2024.130607 - SUPPORT (IN_VITRO)

"Co-culture significantly enhanced the growth of both microbes"

Methane and Carbon Dioxide Mitigation

CROSS_FEEDING

Source Taxon: Methylomicrobium alcaliphilum 20Z

Target Taxon: Chlorella sp. HS2

Metabolites: methane (CHEBI:16183), carbon dioxide (CHEBI:16526)

Biological Processes:

methane metabolic process (GO:0015947)
carbon fixation (GO:0015977)
photosynthesis (GO:0015979)

Evidence

doi:10.1016/j.biortech.2024.130607 - SUPPORT (IN_VITRO)

"remediate in situ CH4 and CO2"
doi:10.1016/j.biortech.2024.130607 - SUPPORT (IN_VITRO)

"nearly an order of magnitude increase in the amount of carbon sequestered in biomass"
doi:10.1016/j.mex.2022.101652 - PARTIAL (COMPUTATIONAL)

"Explicitly models the exchange of in situ produced O2 and CO2 within the coculture"

Saline Metabolic Coupling and pH Recovery

COLONIZATION_FACILITATION

Source Taxon: Chlorella sp. HS2

Target Taxon: Methylomicrobium alcaliphilum 20Z

Biological Processes:

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

Evidence

doi:10.1016/j.biortech.2024.130607 - SUPPORT (IN_VITRO)

"robust metabolic coupling between the two microbes"
doi:10.1016/j.biortech.2024.130607 - SUPPORT (IN_VITRO)

"pH recovery above mild alkaline level was observed in co-cultures."
doi:10.20517/mrr.2023.70 - PARTIAL (COMPUTATIONAL)

"methanotroph-photoautotroph (M-P) coculture..the metabolic interactions within the coculture, how they contribute to the enhanced growth observed in the coculture"

External Resources

Name	Repository	Resource ID
Exact-system primary publication - methane sequestration metabolic coupling Primary publication reporting biological methane sequestration through metabolic coupling between M. alcaliphilum 20Z and Chlorella sp. HS2.	OTHER	doi:10.1016/j.biortech.2024.130607
doi:10.1016/j.biortech.2024.130607 - SUPPORT (IN_VITRO) "Methylomicrobium alcaliphilum 20Z was demonstrated to form a mutualistic association with Chlorella sp. HS2"
NCBI Taxonomy - Methylotuvimicrobium alcaliphilum 20Z NCBI Taxonomy record for Methylotuvimicrobium alcaliphilum 20Z.	OTHER	NCBITaxon:1091494
NCBI BioProject - Methylotuvimicrobium alcaliphilum 20Z genome Genome sequencing BioProject for Methylotuvimicrobium alcaliphilum 20Z.	OTHER	bioproject:PRJEA73721
NCBI Taxonomy - Chlorella sp. HS2 NCBI Taxonomy record for Chlorella sp. HS2.	OTHER	NCBITaxon:2675547

Environmental Factors

Factor	Value	Unit
Salinity	above 3.0%	N/A
doi:10.1016/j.biortech.2024.130607 - SUPPORT (IN_VITRO) "at a salinity level above 3.0%." doi:10.1016/j.biortech.2024.130607 - SUPPORT (IN_VITRO) "co-cultivated in a saline medium."
Methane provision	increased methane provision in enclosed serum bottles	N/A
doi:10.1016/j.biortech.2024.130607 - SUPPORT (IN_VITRO) "increased methane provision in enclosed serum bottles led to saturated methane removal"
Initial inoculum ratio	varied without substantial biomass-yield difference	N/A
doi:10.1016/j.biortech.2024.130607 - SUPPORT (IN_VITRO) "independent of initial inoculum ratios."
Culture pH	pH recovery above mild alkaline level	N/A
doi:10.1016/j.biortech.2024.130607 - SUPPORT (IN_VITRO) "maintained a suitable cultural pH suitable for methanotrophic growth"

Growth Media

Saline methane-fed methanotroph-microalga coculture assay

Atmosphere AEROBIC

Composition

Component	Concentration	Unit	CHEBI
methane	N/A	N/A	CHEBI:16183
carbon dioxide	N/A	N/A	CHEBI:16526

Preparation notes: The source publication supports saline medium, methane-fed enclosed serum bottle experiments, and coculture conditions for M. alcaliphilum 20Z and Chlorella sp. HS2. Detailed medium composition is not asserted here beyond the verified saline, methane, and carbon dioxide context.

Evidence

doi:10.1016/j.biortech.2024.130607

"M. alcaliphilum 20Z and Chlorella sp. HS2 were co-cultivated in a saline medium."

doi:10.1016/j.biortech.2024.130607

"A halotolerant consortium between microalgae and methanotrophic bacteria"