# Eggerthellaceae

The Eggerthellaceae are a family of Gram-positive, rod- or coccus-shaped Actinomycetota. It is the sole family within the order Eggerthellales.
The name Eggerthellaceae is derived from the Latin term Eggerthella, referring to the type genus of the family and the suffix "-ceae," an ending used to denote a family. Together, Eggerthellaceae refers to a family whose nomenclatural type is the genus Eggerthella.

## Biochemical characteristics and molecular signatures

Members of this family are mostly anaerobic, non-motile (with the exception of some Gordonibacter and Senegalimassilia species that exhibit motility), asaccharolytic and do not form spores. Eggerthellaceae species are commonly isolated from human and animal faeces and other human sources such as the colon, vagina, oral cavity and blood. Some species have also been isolated from human samples of periodontal or endodontic infections, Crohn's disease and severe blood bacteremia. The G+C content for Eggerthellaceae species is between 43.4 and 66.3 mol%.
Analysis of genome sequences identified 13 conserved signature indels (CSIs) in diverse proteins that are exclusively present in different Eggerthellaceae species. The proteins containing these CSIs are: contaexcinuclease ABC subunit UvrC, DNA polymerase III subunit alpha, ribonuclease III, tRNA (N6-isopentenyl adenosine(37)-C2)-methylthiotransferase (MiaB), peptide chain release factor 2, 16S rRNA (cytosine(1402)-N(4))-methyltransferase, elongation factor Tu, UDP-N-acetylglucosamine 1-carboxyvinyltransferase DNA polymerase III subunit epsilon, UDP-glucose 4-epimerase and DNA-directed RNA polymerase subunit alpha. The identified CSIs provide reliable and important means to distinguish members of Eggerthellaceae from all other Coriobacteriia as well as other bacteria.

## Phylogeny

The currently accepted taxonomy is based on the List of Prokaryotic names with Standing in Nomenclature (LPSN).
| Nouioui et al. 2018 | conserved signature indels by Gupta & Carro 2021 |
| Coriobacteriales Eggerthellales Slackia Cryptobacterium Denitrobacterium Senegalimassilia Eggerthella Gordonibacter Adlercreutzia | " |
| 16S rRNA based LTP_08_2023 | 120 marker proteins based GTDB 08-RS214 |
| Coriobacteriia Anaerosomatales Anaerosomataceae Parvivirga Atopobiaceae Raoultibacter Denitrobacterium Coriobacteriales Coriobacteriaceae Eggerthellales Rubneribacter Xiamenia Zhang et al. 2022 Eggerthella Gordonibacter Paraeggerthella Arabiibacter Enteroscipio Cryptobacterium Slackia Berryella Ellagibacter Senegalimassilia Adlercreutzia Eggerthellaceae | Eggerthellaceae Slackia Wade et al. 1999 "Anaerotardibacter" Afrizal et al. 2022 Cryptobacterium Nakazawa et al. 1999 Denitrobacterium Anderson et al. 2000 "Ca. Aveggerthella" Gilroy et al. 2021 Berryella Wylensek et al. 2021 "Phoenicibacter" Bilen et al. 2019 Ellagibacter Beltran et al. 2018 Senegalimassilia corrig. Lagier et al. 2014 "Ca. Aphodovivens" Gilroy et al. 2021 Parvibacter Clavel et al. 2013 Adlercreutzia Maruo et al. 2008 Raoultibacter Traore et al. 2022 Gordonibacter Wurdemann et al. 2009 Enteroscipio Danylec et al. 2018 Arabiibacter Lo et al. 2023 Rubneribacter Danylec et al. 2018 Paraeggerthella Wurdemann et al. 2009 Eggerthella Wade et al. 1999 |