Genus in family Succiniclasticum. Pleomorphic rods, 0.5 × 2.0 µm to 0.5 × 5–20 µm. Pleomorphism is medium dependent; in the presence of succinate small rods are transformed into elongated and fragmented rods with multiple branches. Gram-stain-negative, nonmotile, nonspore-forming chemo-organotroph. Propionic acid is the main end product of succinate fermentation. Growth inhibited by fumarate. Growth of satellite colonies around colonies of succinate-producing Escherichia coli cells. Obligately anaerobic. Growth most rapid at 30–37°C. Phylogenetically a member of the family Veillonellaceae, phylum Firmicutes. So far Succiniclasticum ruminis is the closest phylogenetic neighbor.
This genus contains microbial species that can reside in the human gastrointestinal tract. [PMC 4262072]
Microbial Abundance Data: Phascolarctobacterium (Percent of total population with standard deviation [PMID: 22698087])