Overview
Olsenella is a Gram-positive obligate anaerobic genus within the Coriobacteriaceae (Actinobacteria). Species such as O. uli and O. profusa were originally isolated from the oral cavity but are increasingly detected in gut microbiome surveys, particularly in disease states.
Metal Dependencies
Olsenella species require iron and manganese for their fermentative metabolism. Their lactic acid output can lower local pH, which in turn increases the solubility and bioavailability of metal ions — creating a feedback loop that may alter the competitive landscape for metal-dependent organisms in the immediate vicinity.
Ecological Role
Olsenella is a lactic acid fermenter that thrives in carbohydrate-rich, anaerobic environments. In the oral cavity, it contributes to dental caries through acid production. Its presence in the gut likely reflects oral-to-gut translocation during barrier compromise, a pattern shared with atopobium parvulum and fusobacterium nucleatum.
Conditions Associated
Gut enrichment of Olsenella has been reported in inflammatory bowel disease and colorectal cancer cohorts. In the oral niche, it associates with deep carious lesions. Its dual-compartment presence makes it a candidate marker for assessing oral-gut barrier integrity.
Cross-References
- iron — metabolic requirement
- fusobacterium nucleatum — shared oral-to-gut translocation
- colorectal cancer — gut enrichment in disease
- pH sensing — acid production altering metal bioavailability