Mobiluncus and Peptoniphilus

Mobiluncus is one of bacteria reducing trimethylamine oxide to trimethylamine. It was also found to be associated with halitosis and bacterial vaginosis. We documented this bacterium in the gut and vaginal samples of several participants of our microbiome study. A new paper found Mobiluncus in umbilical dirt of the high odor score group. 

Since odor scores did not show a normal distribution, samples were divided into two groups, one with an odor score ≥2.0 and one <2. Well-known resident bacteria of skin, such as Cutibacterium, Staphylococcus, and Corynebacterium, were not detected, whereas some anaerobic bacteria, including Mobiluncus (q-value=2.1E-33), Arcanobacterium (q-value=4.5E-22), and Peptoniphilus (q-value=4.3E-17), were highly abundant in umbilical dirt samples with high odor scores. The same genera were detected when samples were divided into two groups with an odor score ≥1.5 as the criterion.

By a predictive metagenome analysis using Picrust2, the authors identified genes that appeared to be specific to umbilical dirt with high odor scores. Metabolic pathways common to the extracted gene groups were analyzed by GSEA (Gene Set Enrichment Analysis). Anaerobic metabolic pathways, such as methane metabolism and glycolysis/gluconeogenesis, were more abundant in the high odor score group, and secondary metabolite production pathways, such as the biosynthesis of secondary metabolites and quorum sensing, were also identified.

While, Mobiluncus is associated with halitosis and bacterial vaginosis, Peptinophilus contributes to underarm odor by producing chemicals such as butyric acid. Acetobacter is one of species that could be counteracting the undesirable odors in this context. 

REFERENCES

Yano T, Okajima T, Tsuchiya S, Tsujimura H. Microbiota in Umbilical Dirt and Its Relationship with Odor. Microbes Environ. 2023;38(3). doi: 10.1264/jsme2.ME23007. PMID: 37407492.

Valerie M, Milaine T, Aicha N, Roger A, Patrick MJ, Ibrahima D, Nehemie D, Laure N, Angeline B. Survey on Intravaginal Practices among Women of Reproductive Age at the Gynaeco-Obstetric and Pediatric Hospital of Yaounde: Association with Bacterial Vaginosis Caused by Gardnerella Vaginalis and Mobiluncus. International Journal Of Medical Science And Clinical Research Studies. 2023 Jan 30;3(1):121-6.

Gabashvili IS Cutaneous Bacteria in the Gut Microbiome as Biomarkers of Systemic Malodor and People Are Allergic to Me (PATM) Conditions: Insights From a Virtually Conducted Clinical Trial. JMIR Dermatol 2020;3(1):e10508  doi: 10.2196/10508

Zhang L, Hong Q, Yu C, Wang R, Li C, Liu S. Acetobacter sp. improves the undesirable odors of fermented noni (Morinda citrifolia L.) juice. Food Chemistry. 2023 Feb 1;401:134126.