This bacterium was characterised from the faeces of children living in Mali. It is in the group of bacteria commonly referred to as Segmented filamentous bacteria (SFB); known also as
Candidatus Arthromitus (greek for “jointed thread”), as proposed by
Snel et al. (1995), and now named
Anisomitus after the first SFB described in vertebrates by French zoologist Pierre-Paul Grassé
(1925). This bacterium is Gram variable and spore-forming, hybridises with the 16S rRNA-targeted oligonucleotide probe (5’-GGG TAC TTA TTG CGT TTG CGA CGG CAC-3’;
Urdaci et al., 2001), and has a 16S rRNA gene sequence that clusters within the monophyletic group in the
Clostridiaceae that includes SFB from hosts such as the mouse, rat, turkey, chicken, and human. The genome is approximately 1.6 to 1.7Mb in size with a GC content of approximately 30% and includes genes for chemotaxis and the synthesis of flagella. The bacterium has a short form with an apparent tip and forms filaments that include a tip structure at one end. The filaments can be morphologically uneven, with a more smooth and thin morphology closer to the tip and a thickening with increased distance from the tip including the appearance of more bulbous sections that are particularly pronounced after spore formation.