Rods (0.8–1.6 × 1.7–11 µm). Nonsporeforming. Nonmotile. Gram-negative. Obligately anaerobic. On Eggerth–Gagnon agar, colonies are 1–2 mm in diameter, gray to off-white–gray, circular, entire, slightly convex, and smooth. Saccharolytic, with a strictly fermentative type of metabolism. Acetic and succinic acids are the main fermentation products. Growth is inhibited on a medium containing 20% bile. Esculin is hydrolyzed. Indole-negative. The predominant menaquinones are MK-11 and MK-12. Isolated from the chicken cecum.
DNA G+C content (mol%): 52. Type species: Barnesiella viscericola
Characterization of the fecal microbiota of patients undergoing allogeneic hematopoietic stem cell transplantation demonstrated that intestinal colonization with Barnesiella confers resistance to intestinal domination and bloodstream infection with VRE. Our studies indicate that obligate anaerobic bacteria belonging to the Barnesiella genus enable clearance of intestinal VRE colonization and may provide novel approaches to prevent the spread of highly antibiotic-resistant bacteria. [PMID: 23319552]
This genus contains microbial species that can reside in the human gastrointestinal tract. [PMC 4262072] The reintroduction of anaerobic flora with high levels of Barnesiella sp. can clear intestines from highly abundant vancomycin-resistant Enteroccocus in mice [PMC 3861043].
Microbial Abundance Data: Barnesiella (Percent of total population with standard deviation [PMID: 22698087])