Eubacterium

E. rectale#

One of the most abundant butyrate producers in the healthy human colon, often ranking alongside F. prausnitzii in absolute abundance. Ferments dietary fiber (resistant starch, xylan) via the butyryl-CoA:acetate CoA-transferase pathway. Butyrate output supports colonocyte energy metabolism, tight junction integrity, and anti-inflammatory HDAC inhibition.

Depleted in Cardiovascular Disease: part of the butyrate-producing guild lost in CVD patients.^{[1]The potential links between human gut microbiota and cardiovascular health and disease - is there a gut-cardiovascular axis?Catia Almeida, J. Guilherme Goncalves-Nobre, Diogo Alpuim Costa et al. · 2023Open reference 1 ↓}

E. hallii (Anaerobutyricum hallii)#

Reclassified but still widely referenced by its original name. Unique metabolic versatility: converts lactate, acetate, and 1,2-propanediol to butyrate and propionate, acting as a metabolic cross-feeder that recycles fermentation intermediates.

This lactate-to-butyrate conversion is critical during rapid fermentation when lactate accumulates and could otherwise acidify the colonic environment to harmful levels. Produces vitamin B12 (cobalamin), linking its metabolism to Cobalt availability.

E. limosum#

Converts dietary fiber to butyrate; also metabolizes methanol and betaine. Possesses demethylating activity that may affect epigenetic regulation in the colonic epithelium.

Disease Associations#

Cardiovascular disease: E. rectale depleted in CVD patients; its loss reduces butyrate-mediated cardioprotective effects.^{[1]The potential links between human gut microbiota and cardiovascular health and disease - is there a gut-cardiovascular axis?Catia Almeida, J. Guilherme Goncalves-Nobre, Diogo Alpuim Costa et al. · 2023Open reference 1 ↓[2]Alterations in the gut microbiome and metabolism with coronary artery disease severityHonghong Liu, Xi Chen, Xiaomin Hu et al. · 2019Open reference 2 ↓}

IBD: consistently reduced in both Crohn's disease and ulcerative colitis; inversely correlated with inflammatory markers. Polyphenol interventions can partially restore Eubacterium abundance.^{[3]Synergic Interactions between Polyphenols and Gut Microbiota in Mitigating Inflammatory Bowel DiseasesLi H, Christman LM, Li R et al. · 2020Open reference 3 ↓}

Colorectal cancer: depleted in CRC; butyrate loss diminishes HDAC-mediated tumor suppression.^{[4]Multi-omic profiling reveals associations between the gut microbiome, host genome and transcriptome in patients with colorectal cancerShaomin Zou, Chao Yang, Jieping Zhang et al. · 2024Open reference 4 ↓} Type 2 diabetes: reduced; metformin treatment partially restores abundance.

Metal Dependencies#

Iron-sulfur clusters in ferredoxins and butyrate synthesis enzymes are essential for anaerobic metabolism. Butyrate production pathway depends on intact iron (Fe)-S cluster function, making Eubacterium vulnerable to Iron perturbation and heavy metal displacement.

Cobalt is required for B12 synthesis in E. hallii, linking its metabolic capacity to trace metal availability in the Gut-Metal-Microbiome Interactions. Heavy metal exposure Cadmium, Lead depletes Eubacterium alongside other SCFA producers, reducing the colonic butyrate pool.

Key Metabolites#

Butyrate—primary output from E. rectale and E. hallii; HDAC inhibitor, anti-inflammatory, colonocyte fuel. Propionate—produced by E. hallii from 1,2-propanediol; improves insulin sensitivity and reduces hepatic lipogenesis. Vitamin B12—synthesized by E. hallii; essential coenzyme for methylation reactions.

Lactate recycling—E. hallii prevents harmful lactate accumulation by converting it to butyrate.