SPECIES · STRAIN AND FUNCTION PROFILE

Megasphaera elsdenii

Validated caproate producer Primary fermentation · High 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

3assemblies

6MCFA marker genes

33%strain metadata coverage

Name, taxonomy and strain identifiers

Curation status: Exact match imported · Culture collection identifier · checked 2026-07-29. Exact strain-level match; curated BacDive fields imported.

Taxonomic record

Scientific name: Megasphaera elsdenii
Rank: species
NCBI Taxonomy: 907
Database role: Validated caproate producer

LC1 Type strain

Full name: Megasphaera elsdenii (Gutierrez et al. 1959) Rogosa 1971
Culture collections: DSM 20460, ATCC 25940, NCIB 8927, CCUG 64197, JCM 1772, CCUG 6199, CECT 390, CGMCC 1.2720, KCTC 5187, NCFB 2263, NCIMB 8927, VTT E-84221, CIP 106852, AIP 10100
History: Not curated
BacDive: Strain 17130

Morphology and observable traits

Strain	Gram stain	Cell shape	Motility	Spore formation	Colony morphology
LC1	negative	coccus-shaped	no	Not curated	[{"@ref": 8831, "incubation period": "1-2 days"}, {"@ref": 63098, "incubation period": "1 day"}, {"@ref": 119020, "hemolysis ability": "0"}]

Culture and growth conditions

Strain	Medium	Temperature	pH	Atmosphere/result
LC1	PYG MEDIUM (MODIFIED) (DSMZ Medium 104)DSMZ Medium 104 · Name: PYG MEDIUM (modified) (DSMZ Medium 104) Composition: Yeast extract 10.0 g/l Peptone 5.0 g/l Trypticase peptone 5.0 g/l Beef extract 5.0 g/l Glucose 5.0 g/l L-Cysteine HCl x H2O 0.5 g/l NaHCO3 0.4 g/l NaCl 0.08 g/l K2HPO4 0.04 g/l KH2PO4 0.04 g/l MgSO4 x 7 H2O 0.02 g/l CaCl2 x 2 H2O 0.01 g/l Hemin 0.005 g/l Ethanol 0.0038 g/l Resazurin 0.001 g/l Tween 80 Vitamin K1 NaOH Distilled water	37.00 °C	—	— · yes
LC1	CIP Medium 20 ·	37.00 °C	—	— · yes
LC1	MEDIUM 20 - for Anaerobic bacteria · Agar (15.000 g);Glucose (5.000 g);Yeast extract (20.000 g);Tryptone (30.000 g);Cysteine hydrochloride (0.500 g);distilled water (1000.000 ml);Hemin solution -M00149 (25.000 ml)	37.00 °C	—	— · yes

Documented condition ranges

Profile	pH	Temperature	Electron donors	Substrates/reactor
Documented growth/production range	4.50–8.00; optimum 6.50	25.00–40.00 °C; optimum 37.00	lactate, glucose	lactate, glucose; batch; strain-dependent continuous culture evidence
BacDive documented cultivation conditions	?–?; optimum ?	37.00–37.00 °C; optimum ?	Not curated	—; culture-collection cultivation
Species-level documented cultivation conditions	?–?; optimum ?	37.00–37.00 °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
Product	valerate	Curator assertionExisting mcfaKB curator phenotype summaries	0.800	Not recorded
Substrate	acetate	Curator assertionExisting mcfaKB curator phenotype summaries	0.800	Not recorded
Substrate	glucose	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
LC1	Not curated	—	Not curated	Not curated	52.700%

Sequence information

Genome assemblies

Accession	Source	Level	Size/GC	Quality	BioProject
GCA_000283495.2	NCBI GenBank	Chromosome	2474718 bp / 53.000%	—% complete; —% contamination	PRJEA70535
GCA_052399495.1	NCBI GenBank	Complete Genome	2768644 bp / 52.500%	—% complete; —% contamination	PRJNA1310739
GCF_003010495.1	NCBI RefSeq	—	— bp / —%	—% complete; —% contamination	PRJNA437124

Marker and ribosomal sequences

Strain	Type	Accession	Length	Description
LC1	16S rRNA	LC036319	1525 bp	Megasphaera elsdenii gene for 16S ribosomal RNA, partial sequence, strain: JCM 1772
LC1	Genome	GCA_003010495	— bp	ASM301049v1 assembly for Megasphaera elsdenii DSM 20460 ATCC 25940
LC1	Genome	GCA_000283495	— bp	ASM28349v2 assembly for Megasphaera elsdenii DSM 20460
LC1	16S rRNA	AB609704	1174 bp	Megasphaera elsdenii gene for 16S rRNA, partial sequence, strain: DSM 20460, type A
LC1	16S rRNA	AB609705	1174 bp	Megasphaera elsdenii gene for 16S rRNA, partial sequence, strain: DSM 20460, type B
LC1	16S rRNA	U95027	1426 bp	Megasphaera elsdenii ATCC 25940 16S ribosomal RNA gene, partial sequence

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 6 annotation-derived MCFA genes

Gene	Locus	Function	Protein	Orthogroup
bcd	MELS_0461	Butyryl-CoA dehydrogenase (1.3.8.1)	CCC72684.1	—
crt	MELS_0462	3-hydroxybutyryl-CoA dehydratase (4.2.1.55)	CCC72685.1	—
bcd	MELS_0747	Butyryl-CoA dehydrogenase (1.3.8.1)	CCC72969.1	—
ldh	MELS_1294	L-lactate dehydrogenase (1.1.1.27)	CCC73515.1	—
hbd	MELS_1448	3-hydroxybutyryl-CoA dehydrogenase (1.1.1.157)	CCC73669.1	—
crt	MELS_1449	3-hydroxybutyryl-CoA dehydratase (4.2.1.55)	CCC73670.1	—

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_052399495.1	bcd_etf_module	1 / 3	Incomplete
GCA_052399495.1	ethanol_entry_support	0 / 1	Incomplete
GCA_052399495.1	fatty_acid_biosynthesis_core	3 / 8	Incomplete
GCA_052399495.1	lactate_entry_support	1 / 2	Incomplete
GCA_052399495.1	reverse_beta_oxidation_core	1 / 4	Incomplete
GCA_052399495.1	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_052399495.1WP_074787045.1 · pyruvate carboxylase	Medium · Needs review		0 decisionsretain confidence tier and orthogroup-support fields during import
bcdbutyryl-CoA dehydrogenase	GCA_052399495.1WP_014017064.1 · acyl-CoA dehydrogenase	Medium · Needs review		0 decisionsretain confidence tier and orthogroup-support fields during import
bcdbutyryl-CoA dehydrogenase	GCA_052399495.1WP_014015428.1 · acyl-CoA dehydrogenase	Medium · Needs review		0 decisionsretain confidence tier and orthogroup-support fields during import
bcdbutyryl-CoA dehydrogenase	GCA_052399495.1WP_014015710.1 · acyl-CoA dehydrogenase	Medium · Needs review		0 decisionsretain confidence tier and orthogroup-support fields during import
bcdbutyryl-CoA dehydrogenase	GCA_052399495.1WP_444707069.1 · acyl-CoA dehydrogenase family protein	Medium · Needs review		0 decisionsretain confidence tier and orthogroup-support fields during import
bcdbutyryl-CoA dehydrogenase	GCA_052399495.1WP_022497660.1 · acyl-CoA dehydrogenase family protein	Medium · Needs review		0 decisionsretain confidence tier and orthogroup-support fields during import
coatbutyrate/acetoacetate CoA-transferase	GCA_052399495.1WP_041647040.1 · CoA transferase subunit B	Medium · Approved candidate	specific_product_name	0 decisionsstrong profile plus independent annotation support: specific_product_name
crtcrotonase/enoyl-CoA hydratase	GCA_052399495.1WP_022497707.1 · short-chain-enoyl-CoA hydratase	Medium · Needs review	specific_product_name	0 decisionsextreme per-proteome copy number; profile alone is not function-specific
crtcrotonase/enoyl-CoA hydratase	GCA_052399495.1WP_014015429.1 · enoyl-CoA hydratase-related protein	Medium · Needs review	specific_product_name	0 decisionsextreme per-proteome copy number; profile alone is not function-specific
crtcrotonase/enoyl-CoA hydratase	GCA_052399495.1WP_444707321.1 · enoyl-CoA hydratase/isomerase family 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_052399495.1WP_014017062.1 · 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_052399495.1WP_014016927.1 · 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_052399495.1WP_014017063.1 · 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_052399495.1WP_014016928.1 · 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_052399495.1WP_027894706.1 · ACP S-malonyltransferase	Medium · Approved candidate	gene_symbol	0 decisionsstrong profile plus independent annotation support: gene_symbol
fabF3-oxoacyl-ACP synthase II	GCA_052399495.1WP_014015037.1 · beta-ketoacyl-ACP synthase II	Medium · Approved candidate	gene_symbol	0 decisionsstrong profile plus independent annotation support: gene_symbol
fabG3-oxoacyl-ACP reductase	GCA_052399495.1WP_014015040.1 · 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_052399495.1WP_444707279.1 · gluconate 5-dehydrogenase	Medium · Needs review		0 decisionsextreme per-proteome copy number; profile alone is not function-specific
fabG3-oxoacyl-ACP reductase	GCA_052399495.1WP_014016735.1 · 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_052399495.1WP_444706978.1 · SDR family NAD(P)-dependent oxidoreductase	Medium · Needs review	OG0000242	0 decisionsextreme per-proteome copy number; profile alone is not function-specific
fabH3-oxoacyl-ACP synthase III	GCA_052399495.1WP_014015042.1 · beta-ketoacyl-ACP synthase III	Medium · Needs review		0 decisionsno bridge-supported orthogroup; require domain, motif, or neighborhood confirmation
fabKenoyl-ACP reductase FabK	GCA_052399495.1WP_014015038.1 · NAD(P)H-dependent flavin oxidoreductase	Medium · Needs review		0 decisionsno bridge-supported orthogroup; require domain, motif, or neighborhood confirmation
fabLenoyl-ACP reductase FabL	GCA_052399495.1WP_014015040.1 · 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_052399495.1WP_444707279.1 · gluconate 5-dehydrogenase	Medium · Needs review		0 decisionsextreme per-proteome copy number; profile alone is not function-specific
fabLenoyl-ACP reductase FabL	GCA_052399495.1WP_014016735.1 · SDR family NAD(P)-dependent oxidoreductase	Medium · Needs review		0 decisionsextreme per-proteome copy number; profile alone is not function-specific
fabZ3-hydroxyacyl-ACP dehydratase	GCA_052399495.1WP_014015064.1 · 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_052399495.1WP_014016399.1 · 3-hydroxybutyryl-CoA dehydrogenase	Medium · Needs review		0 decisionsretain confidence tier and orthogroup-support fields during import
lctPL-lactate permease	GCA_052399495.1WP_014015704.1 · L-lactate permease	High · Approved candidate	OG0000731	0 decisionsstrong profile and bridge orthogroup support
lctPL-lactate permease	GCA_052399495.1WP_014017157.1 · L-lactate permease	High · Approved candidate	OG0000731	0 decisionsstrong profile and bridge orthogroup support
ldhL-lactate dehydrogenase	GCA_052399495.1WP_444707422.1 · lactate/malate family dehydrogenase	Medium · Needs review		0 decisionsretain confidence tier and orthogroup-support fields during import
rnfARnf complex subunit A	GCA_052399495.1WP_014015121.1 · electron transport complex protein RnfA	High · Approved candidate	OG0001169	0 decisionsstrong profile and bridge orthogroup support
rnfBRnf complex subunit B	GCA_052399495.1WP_022497725.1 · 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_052399495.1WP_014015125.1 · electron transport complex subunit RsxC	High · Approved candidate	OG0001114	0 decisionsstrong profile and bridge orthogroup support
rnfDRnf complex subunit D	GCA_052399495.1WP_014015124.1 · RnfABCDGE type electron transport complex subunit D	High · Approved candidate	OG0001182	0 decisionsstrong profile and bridge orthogroup support
rnfERnf complex subunit E	GCA_052399495.1WP_022497724.1 · electron transport complex subunit RsxE	High · Approved candidate	OG0001153	0 decisionsstrong profile and bridge orthogroup support
rnfGRnf complex subunit G	GCA_052399495.1WP_014015123.1 · RnfABCDGE type electron transport complex subunit G	High · Approved candidate	OG0001292	0 decisionsstrong profile and bridge orthogroup support
thlacetyl-CoA acetyltransferase/thiolase	GCA_052399495.1WP_014015981.1 · acetyl-CoA C-acetyltransferase	High · Approved candidate	OG0005114	0 decisionsstrong profile and bridge orthogroup support
thlacetyl-CoA acetyltransferase/thiolase	GCA_052399495.1WP_014015982.1 · acetyl-CoA C-acetyltransferase	High · Approved candidate	OG0005114	0 decisionsstrong profile and bridge orthogroup support

Literature and provenance

Study	DOI	Public data
Genome Sequence of the Ruminal Bacterium Megasphaera elsdenii	10.1128/JB.05861-11	PRJEA70535

Profile evidence

BacDive strain record 17130: Megasphaera elsdenii LC1 — Curator assertion

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