SPECIES · STRAIN AND FUNCTION PROFILE

Megasphaera hexanoica

Validated caproate producer Reverse β-oxidation chain elongation · High Energy conservation · Medium

Role labels distinguish demonstrated caproate production from community association; validate at strain level before causal interpretation.

1strain profiles

2assemblies

4MCFA marker genes

67%strain metadata coverage

Name, taxonomy and strain identifiers

Curation status: Exact match imported · Strain designation · checked 2026-07-29. Exact strain-level match; curated BacDive fields imported.

Taxonomic record

Scientific name: Megasphaera hexanoica
Rank: species
NCBI Taxonomy: 1675036
Database role: Validated caproate producer

MH Type strain

Full name: Not curated
Culture collections: KCCM 43214, JCM 31403, KFCC 11466P
History: JCM <-- B.-I. Sang; Hanyang Univ., South Korea; KFCC 11466P.
BacDive: Strain 140555

Morphology and observable traits

Strain	Gram stain	Cell shape	Motility	Spore formation	Colony morphology
MH	negative	coccus-shaped	no	Not curated	{"@ref": 43304, "colony size": "0.5-1 mm", "colony color": "slightly yellowish, convex and opaque", "colony shape": "circular", "incubation period": "6-7 days", "medium used": "mPYF"}

Culture and growth conditions

Strain	Medium	Temperature	pH	Atmosphere/result
MH	mPYF ·	30.00 °C	—	anaerobe · yes

Documented condition ranges

Profile	pH	Temperature	Electron donors	Substrates/reactor
Documented growth/production range	5.50–7.50; optimum 6.50	30.00–40.00 °C; optimum 37.00	lactate, fructose	lactate, fructose; batch; strain-dependent continuous culture evidence
BacDive documented cultivation conditions	?–?; optimum ?	30.00–30.00 °C; optimum ?	Not curated	—; culture-collection cultivation
Species-level documented cultivation conditions	?–?; optimum ?	30.00–40.00 °C; optimum ?	Not curated	—; species-level culture records

Physiology and metabolism

Documented substrates and products

Only approved assertions are shown. Results may be strain- and condition-specific.

Relationship	Compound/source term	Evidence	Confidence	Condition
Product	butyrate	Curator assertionExisting mcfaKB curator phenotype summaries	0.800	Not recorded
Product	caproate	Curator assertionExisting mcfaKB curator phenotype summaries	0.800	Not recorded
Substrate	acetate	Curator assertionExisting mcfaKB curator phenotype summaries	0.800	Not recorded
Substrate	lactate	Curator assertionExisting mcfaKB curator phenotype summaries	0.800	Not recorded

Predicted metabolic capabilities

Genome-derived hypotheses requiring review—not demonstrated substrates or products.

Capability	Basis/status	Confidence	Assemblies	Limitation
No genome-derived capabilities available.

Isolation, environment and safety

Strain	Isolation source	Category/location	Oxygen tolerance	Biosafety	GC content
MH	Not curated	—	anaerobe	Not curated	51.800%

Sequence information

Genome assemblies

Accession	Source	Level	Size/GC	Quality	BioProject
GCA_003315775.1	NCBI GenBank	Complete Genome	— bp / —%	—% complete; —% contamination	PRJNA287738
GCA_043520715.1	NCBI GenBank	Complete Genome	2882434 bp / 49.000%	—% complete; —% contamination	PRJNA287738

Marker and ribosomal sequences

Strain	Type	Accession	Length	Description
MH	16S rRNA	KX021300	— bp	Megasphaera hexanoica strain MH 16S ribosomal RNA gene, partial sequence
MH	Genome	GCA_003315775	— bp	ASM331577v1 assembly for Megasphaera hexanoica MH

MCFA pathways and genes

Reverse β-oxidation (chain elongation)3 of 5 functions60%60%

Fatty acid biosynthesis (FAS II)0 of 7 functions0%0%

Show 4 annotation-derived MCFA genes

Gene	Locus	Function	Protein	Orthogroup
ldh	ACT01_00410	L-lactate dehydrogenase (1.1.1.27)	AXB80829.1	—
acat	ACT01_07765	Acetyl-CoA acetyltransferase (2.3.1.9)	AXB82143.1	—
crt	ACT01_10830	3-hydroxybutyryl-CoA dehydratase (4.2.1.55)	AXB82690.1	—
hbd	ACT01_10835	3-hydroxybutyryl-CoA dehydrogenase (1.1.1.157)	AXB82691.1	—

Curator-approved marker pathway assessments

These summaries use approved candidate predictions only and update after every review decision.

Assembly	Pathway rule	Approved markers	Status
GCA_043520715.1	bcd_etf_module	1 / 3	Incomplete
GCA_043520715.1	ethanol_entry_support	0 / 1	Incomplete
GCA_043520715.1	fatty_acid_biosynthesis_core	3 / 8	Incomplete
GCA_043520715.1	lactate_entry_support	1 / 2	Incomplete
GCA_043520715.1	reverse_beta_oxidation_core	2 / 4	Incomplete
GCA_043520715.1	rnf_complex	6 / 6	Complete

Profile-HMM marker predictions

Approved candidates and unresolved review calls are genomic hypotheses, not evidence of expression or MCFA production.

Marker	Assembly / protein	Confidence and status	Support	Review history
accCacetyl-CoA carboxylase biotin carboxylase	GCA_043520715.1WP_394522511.1 · pyruvate carboxylase	Medium · Needs review		0 decisionsretain confidence tier and orthogroup-support fields during import
bcdbutyryl-CoA dehydrogenase	GCA_043520715.1WP_059076372.1 · acyl-CoA dehydrogenase	Medium · Needs review		0 decisionsretain confidence tier and orthogroup-support fields during import
bcdbutyryl-CoA dehydrogenase	GCA_043520715.1WP_059077323.1 · acyl-CoA dehydrogenase	Medium · Needs review		0 decisionsretain confidence tier and orthogroup-support fields during import
bcdbutyryl-CoA dehydrogenase	GCA_043520715.1WP_059076926.1 · acyl-CoA dehydrogenase family protein	Medium · Needs review		0 decisionsretain confidence tier and orthogroup-support fields during import
bcdbutyryl-CoA dehydrogenase	GCA_043520715.1WP_059077342.1 · acyl-CoA dehydrogenase family protein	Medium · Needs review		0 decisionsretain confidence tier and orthogroup-support fields during import
crtcrotonase/enoyl-CoA hydratase	GCA_043520715.1WP_059077295.1 · enoyl-CoA hydratase-related protein	Medium · Needs review	specific_product_name	0 decisionsextreme per-proteome copy number; profile alone is not function-specific
etfAelectron transfer flavoprotein alpha subunit	GCA_043520715.1WP_075582160.1 · electron transfer flavoprotein subunit alpha/FixB family protein	Medium · Needs review		0 decisionsretain confidence tier and orthogroup-support fields during import
etfAelectron transfer flavoprotein alpha subunit	GCA_043520715.1WP_075582278.1 · electron transfer flavoprotein subunit alpha/FixB family protein	Medium · Needs review		0 decisionsretain confidence tier and orthogroup-support fields during import
etfBelectron transfer flavoprotein beta subunit	GCA_043520715.1WP_059077322.1 · electron transfer flavoprotein subunit beta/FixA family protein	High · Approved candidate	OG0001139	0 decisionsstrong profile and bridge orthogroup support
etfBelectron transfer flavoprotein beta subunit	GCA_043520715.1WP_113856004.1 · electron transfer flavoprotein subunit beta/FixA family protein	Medium · Needs review		0 decisionsretain confidence tier and orthogroup-support fields during import
fabDmalonyl-CoA--ACP transacylase	GCA_043520715.1WP_059076791.1 · ACP S-malonyltransferase	Medium · Approved candidate	gene_symbol	0 decisionsstrong profile plus independent annotation support: gene_symbol
fabF3-oxoacyl-ACP synthase II	GCA_043520715.1WP_059076795.1 · beta-ketoacyl-ACP synthase II	Medium · Approved candidate	gene_symbol	0 decisionsstrong profile plus independent annotation support: gene_symbol
fabG3-oxoacyl-ACP reductase	GCA_043520715.1WP_059076792.1 · 3-oxoacyl-[acyl-carrier-protein] reductase	High · Approved candidate	OG0000008gene_symbol	0 decisionsstrong profile and bridge orthogroup support; annotation support: gene_symbol
fabG3-oxoacyl-ACP reductase	GCA_043520715.1WP_059077071.1 · SDR family NAD(P)-dependent oxidoreductase	Medium · Needs review		0 decisionsextreme per-proteome copy number; profile alone is not function-specific
fabG3-oxoacyl-ACP reductase	GCA_043520715.1WP_075581779.1 · SDR family NAD(P)-dependent oxidoreductase	Medium · Needs review		0 decisionsextreme per-proteome copy number; profile alone is not function-specific
fabG3-oxoacyl-ACP reductase	GCA_043520715.1WP_059076365.1 · SDR family NAD(P)-dependent oxidoreductase	High · Needs review	OG0000008	0 decisionsextreme per-proteome copy number; profile alone is not function-specific
fabG3-oxoacyl-ACP reductase	GCA_043520715.1WP_075581507.1 · gluconate 5-dehydrogenase	Medium · Needs review		0 decisionsextreme per-proteome copy number; profile alone is not function-specific
fabG3-oxoacyl-ACP reductase	GCA_043520715.1WP_059076392.1 · SDR family NAD(P)-dependent oxidoreductase	Medium · Needs review		0 decisionsextreme per-proteome copy number; profile alone is not function-specific
fabG3-oxoacyl-ACP reductase	GCA_043520715.1WP_113855996.1 · SDR family NAD(P)-dependent oxidoreductase	Medium · Needs review		0 decisionsextreme per-proteome copy number; profile alone is not function-specific
fabG3-oxoacyl-ACP reductase	GCA_043520715.1WP_113855339.1 · SDR family NAD(P)-dependent oxidoreductase	Medium · Needs review		0 decisionsextreme per-proteome copy number; profile alone is not function-specific
fabG3-oxoacyl-ACP reductase	GCA_043520715.1WP_059077119.1 · SDR family oxidoreductase	Medium · Needs review		0 decisionsextreme per-proteome copy number; profile alone is not function-specific
fabG3-oxoacyl-ACP reductase	GCA_043520715.1WP_113855872.1 · SDR family oxidoreductase	Medium · Needs review	OG0000242	0 decisionsextreme per-proteome copy number; profile alone is not function-specific
fabH3-oxoacyl-ACP synthase III	GCA_043520715.1WP_059076790.1 · beta-ketoacyl-ACP synthase III	Medium · Needs review		0 decisionsno bridge-supported orthogroup; require domain, motif, or neighborhood confirmation
fabKenoyl-ACP reductase FabK	GCA_043520715.1WP_172793345.1 · nitronate monooxygenase family protein	Medium · Needs review		0 decisionsno bridge-supported orthogroup; require domain, motif, or neighborhood confirmation
fabLenoyl-ACP reductase FabL	GCA_043520715.1WP_059076792.1 · 3-oxoacyl-[acyl-carrier-protein] reductase	Medium · Needs review		0 decisionsextreme per-proteome copy number; profile alone is not function-specific
fabLenoyl-ACP reductase FabL	GCA_043520715.1WP_075581779.1 · SDR family NAD(P)-dependent oxidoreductase	Medium · Needs review		0 decisionsextreme per-proteome copy number; profile alone is not function-specific
fabLenoyl-ACP reductase FabL	GCA_043520715.1WP_059077071.1 · SDR family NAD(P)-dependent oxidoreductase	Medium · Needs review		0 decisionsextreme per-proteome copy number; profile alone is not function-specific
fabLenoyl-ACP reductase FabL	GCA_043520715.1WP_059076392.1 · SDR family NAD(P)-dependent oxidoreductase	Medium · Needs review		0 decisionsextreme per-proteome copy number; profile alone is not function-specific
fabLenoyl-ACP reductase FabL	GCA_043520715.1WP_075581507.1 · gluconate 5-dehydrogenase	Medium · Needs review		0 decisionsextreme per-proteome copy number; profile alone is not function-specific
fabLenoyl-ACP reductase FabL	GCA_043520715.1WP_059076365.1 · SDR family NAD(P)-dependent oxidoreductase	Medium · Needs review		0 decisionsextreme per-proteome copy number; profile alone is not function-specific
fabLenoyl-ACP reductase FabL	GCA_043520715.1WP_113855339.1 · SDR family NAD(P)-dependent oxidoreductase	Medium · Needs review		0 decisionsextreme per-proteome copy number; profile alone is not function-specific
fabLenoyl-ACP reductase FabL	GCA_043520715.1WP_113855996.1 · SDR family NAD(P)-dependent oxidoreductase	Medium · Needs review		0 decisionsextreme per-proteome copy number; profile alone is not function-specific
fabLenoyl-ACP reductase FabL	GCA_043520715.1WP_059077119.1 · SDR family oxidoreductase	Medium · Needs review		0 decisionsextreme per-proteome copy number; profile alone is not function-specific
fabZ3-hydroxyacyl-ACP dehydratase	GCA_043520715.1WP_113855460.1 · 3-hydroxyacyl-ACP dehydratase FabZ	High · Approved candidate	OG0000074gene_symbol	0 decisionsstrong profile and bridge orthogroup support; annotation support: gene_symbol
hbd3-hydroxybutyryl-CoA dehydrogenase	GCA_043520715.1WP_059077296.1 · 3-hydroxybutyryl-CoA dehydrogenase	Medium · Needs review		0 decisionsretain confidence tier and orthogroup-support fields during import
hbd3-hydroxybutyryl-CoA dehydrogenase	GCA_043520715.1WP_394522366.1 · 3-hydroxyacyl-CoA dehydrogenase family protein	High · Approved candidate	OG0000153	0 decisionsstrong profile and bridge orthogroup support
lctPL-lactate permease	GCA_043520715.1WP_113856469.1 · L-lactate permease	High · Approved candidate	OG0000731	0 decisionsstrong profile and bridge orthogroup support
lctPL-lactate permease	GCA_043520715.1WP_113856294.1 · L-lactate permease	High · Approved candidate	OG0000731	0 decisionsstrong profile and bridge orthogroup support
ldhL-lactate dehydrogenase	GCA_043520715.1WP_059076901.1 · L-lactate dehydrogenase	Medium · Needs review		0 decisionsretain confidence tier and orthogroup-support fields during import
rnfARnf complex subunit A	GCA_043520715.1WP_059076695.1 · electron transport complex protein RnfA	High · Approved candidate	OG0001169	0 decisionsstrong profile and bridge orthogroup support
rnfBRnf complex subunit B	GCA_043520715.1WP_059076696.1 · RnfABCDGE type electron transport complex subunit B	High · Approved candidate	OG0001404gene_symbol	0 decisionsstrong profile and bridge orthogroup support; annotation support: gene_symbol
rnfCRnf complex subunit C	GCA_043520715.1WP_113855450.1 · 4Fe-4S dicluster domain-containing protein	Medium · Needs review		0 decisionsretain confidence tier and orthogroup-support fields during import
rnfCRnf complex subunit C	GCA_043520715.1WP_059076691.1 · electron transport complex subunit RsxC	High · Approved candidate	OG0001114	0 decisionsstrong profile and bridge orthogroup support
rnfDRnf complex subunit D	GCA_043520715.1WP_113855419.1 · RnfABCDGE type electron transport complex subunit D	High · Approved candidate	OG0001182	0 decisionsstrong profile and bridge orthogroup support
rnfERnf complex subunit E	GCA_043520715.1WP_059076694.1 · electron transport complex subunit RsxE	High · Approved candidate	OG0001153	0 decisionsstrong profile and bridge orthogroup support
rnfGRnf complex subunit G	GCA_043520715.1WP_059076693.1 · RnfABCDGE type electron transport complex subunit G	High · Approved candidate	OG0001292	0 decisionsstrong profile and bridge orthogroup support
thlacetyl-CoA acetyltransferase/thiolase	GCA_043520715.1WP_059075873.1 · acetyl-CoA C-acetyltransferase	High · Approved candidate	OG0005114	0 decisionsstrong profile and bridge orthogroup support

Literature and provenance

Study	DOI	Public data
No organism-linked literature indexed yet.

Profile evidence

BacDive strain record 140555: Megasphaera hexanoica MH — Curator assertion

External databases can change. mcfaKB records source links and separates experimentally reported, curator-entered and predicted information.