Soybean N-Fixation Simplified SynCom

Community ID CommunityMech:000064

Ecological State ENGINEERED

Environment rhizosphere
ENVO:00005801 · HabitatMech ↗

A simplified synthetic community (sfSynCom) for enhanced symbiotic nitrogen fixation in soybean, based on core-helper strain interactions. The consortium consists of Bradyrhizobium elkanii BXYD3 as the core nitrogen-fixing symbiont and two Pantoea helper strains. The helper strains produce acyl homoserine lactones (AHL) that enhance colonization and infection of soybean roots by B. elkanii through quorum sensing, significantly improving nodulation and nitrogen fixation compared to single-strain inoculation.

Taxonomy

Taxon	Ontology ID	Functional Roles	Abundance
Bradyrhizobium elkanii BXYD3 — ontology label: Bradyrhizobium elkanii	NCBITaxon:29448 · TaxonMech · TraitMech	NITROGEN_FIXING_SYMBIONT	DOMINANT
PMID:40052412 - SUPPORT (IN_VITRO) "Here, we propose a strategy for constructing a simplified and functional SynCom (sfSynCom) by using elite helper strains that significantly improve the beneficial functions of the core symbiotic strain, here Bradyrhizobium elkanii BXYD3, to sustain the growth of soybean (Glycine max)"
Pantoea sp. helper strain 1 — ontology label: Pantoea	NCBITaxon:53335 · TaxonMech · TraitMech	SYNTROPHIC_PARTNER	COMMON
PMID:40052412 - SUPPORT (IN_VITRO) "Two of these helper strains assigned to the Pantoea taxon produce acyl homoserine lactones, which significantly enhanced the colonization and infection of soybean by BXYD3"
Pantoea sp. helper strain 2 — ontology label: Pantoea	NCBITaxon:53335 · TaxonMech · TraitMech	SYNTROPHIC_PARTNER	COMMON
PMID:40052412 - SUPPORT (IN_VITRO) "Two of these helper strains assigned to the Pantoea taxon produce acyl homoserine lactones, which significantly enhanced the colonization and infection of soybean by BXYD3"
Glycine max	NCBITaxon:3847 · TaxonMech · TraitMech	PRIMARY_PRODUCER	N/A
PMID:40052412 - SUPPORT (IN_VITRO) "Here, we propose a strategy for constructing a simplified and functional SynCom (sfSynCom) by using elite helper strains that significantly improve the beneficial functions of the core symbiotic strain, here Bradyrhizobium elkanii BXYD3, to sustain the growth of soybean (Glycine max)"

Ecological Interactions

ℹ️ No detailed ecological interaction data is available for this community.

This record may be a metabolic model or minimal entry containing only taxonomy and external resource links.

Knowledge gaps & discussions (1)

KNOWLEDGE_GAP OPEN What exact sfSynCom membership and source strain identities do the two ordinal Pantoea helper entries represent?

The abstract reports two Pantoea helper strains among the helpers and positive outcomes for the final sfSynCom, but does not establish that the final community contains only BXYD3 and those two helpers or map the ordinal labels to published strain identifiers. Three strain/formulation-attributed nodes and two arrows are withheld, not a rejection of the source's positive observations. Consortium-level improvement also does not establish reciprocal benefit for each encoded pair. EuropePMC supplied no PMCID; Wiley and journal-site full-text requests returned HTTP403. This is a bounded access and identity gap, not proof that full text or exact membership does not exist. Keep needs_research and resolve #1820 before restoring attribution. Identity/taxonomy and non-graph protocol blocks are preserved, not certified; no enhancement procedures are added.

2 evidence item(s)

IN_VIVO PARTIAL PMID:40052412

Two of these helper strains assigned to the Pantoea taxon produce acyl homoserine lactones, which significantly enhanced the colonization and infection of soybean by BXYD3

Preserves the positive source observation but does not name the helper strains or establish the complete final formulation.

IN_VIVO PARTIAL PMID:40052412

This sfSynCom based on the core-helper strategy was more effective at promoting nodulation than inoculation with BXYD3 alone and achieved effects comparable to those of a complex elite SynCom previously constructed on the basis of potential beneficial functions between microbes and plants alone

Preserves the reported consortium-level comparison without assigning it to an unverified three-member formulation or reciprocal pairwise benefit.

Environmental Factors

Factor	Value	Unit
Quorum sensing regulation	AHL-mediated	N/A
Nodulation efficiency	enhanced	N/A
Agricultural application	sustainable nitrogen input	N/A

Growth Media

Yeast Mannitol Agar (YMA) for rhizobial culture (CultureMech:002946)

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pH 6.8

Temperature 28 degrees Celsius

Atmosphere AEROBIC

Composition

Component	Concentration	Unit	CHEBI
Mannitol · MediaIngredientMech	10	g/L	CHEBI:16899
Yeast extract · MediaIngredientMech	0.5	g/L	N/A
Dipotassium phosphate · MediaIngredientMech	0.5	g/L	CHEBI:131527
Magnesium sulfate · MediaIngredientMech	0.2	g/L	CHEBI:32599
Sodium chloride · MediaIngredientMech	0.1	g/L	CHEBI:26710
Agar · MediaIngredientMech	15	g/L	N/A
Peptone · MediaIngredientMech	3	G_PER_L	N/A
CaCO3 · MediaIngredientMech	10	G_PER_L	N/A

Preparation notes: Standard medium for Bradyrhizobium elkanii and other slow-growing rhizobia. Supports growth of nitrogen-fixing symbionts isolated from soybean nodules. Colonies typically appear after 3-5 days incubation.

Evidence

PMID:40052412

"Here, we propose a strategy for constructing a simplified and functional SynCom (sfSynCom) by using elite helper strains that significantly improve the beneficial functions of the core symbiotic strain, here Bradyrhizobium elkanii BXYD3, to sustain the growth of soybean (Glycine max)"

Luria-Bertani (LB) medium for Pantoea helper strains (CultureMech:009674)

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pH 7.0

Temperature 30 degrees Celsius

Atmosphere FACULTATIVE_ANAEROBIC

Composition

Component	Concentration	Unit	CHEBI
Tryptone · MediaIngredientMech	10	g/L	N/A
Yeast extract · MediaIngredientMech	5	g/L	N/A
Sodium chloride · MediaIngredientMech	10	g/L	CHEBI:26710
Distilled water · MediaIngredientMech	1	G_PER_L	N/A
NaCl · MediaIngredientMech	10	G_PER_L	N/A

Preparation notes: Rich medium for cultivation of Pantoea helper strains that produce acyl homoserine lactones (AHL). Faster-growing than Bradyrhizobium, typically reaching stationary phase within 24 hours.

Evidence

PMID:40052412

"Two of these helper strains assigned to the Pantoea taxon produce acyl homoserine lactones, which significantly enhanced the colonization and infection of soybean by BXYD3"

Nitrogen-free plant nutrient solution for soybean growth (CultureMech:015438)

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pH 6.5

Temperature 25 degrees Celsius

Composition

Component	Concentration	Unit	CHEBI
Potassium phosphate · MediaIngredientMech	1	mM	CHEBI:131527
Magnesium sulfate · MediaIngredientMech	1	mM	CHEBI:32599
Calcium chloride · MediaIngredientMech	2	mM	CHEBI:3312
Iron-EDTA · MediaIngredientMech	100	μM	N/A

Preparation notes: Nitrogen-free growth medium for soybean to study symbiotic nitrogen fixation. Leonard jar system or vermiculite substrate watered with nitrogen-free nutrient solution. Plants inoculated with sfSynCom (Bradyrhizobium BXYD3 plus Pantoea helper strains) to assess nodulation efficiency and nitrogen fixation capacity.

Evidence

PMID:40052412

"This sfSynCom based on the core-helper strategy was more effective at promoting nodulation than inoculation with BXYD3 alone and achieved effects comparable to those of a complex elite SynCom previously constructed on the basis of potential beneficial functions between microbes and plants alone"

Cross-Mech Suite Links

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

HabitatMech: rhizosphere ↗ TaxonMech: Bradyrhizobium elkanii BXYD3 ↗ TraitMech: Bradyrhizobium elkanii BXYD3 ↗ TaxonMech: Pantoea sp. helper strain 1 ↗ TraitMech: Pantoea sp. helper strain 1 ↗ TaxonMech: Pantoea sp. helper strain 2 ↗ TraitMech: Pantoea sp. helper strain 2 ↗ TaxonMech: Glycine max ↗ TraitMech: Glycine max ↗ CultureMech Growth Media ↗ PathwayMech Pathways ↗