Details

Autor(en) / Beteiligte

• Lund, Marie B
• Mogensen, Mathias F
• Marshall, Ian P G
• Albertsen, Mads
• Viana, Flávia
• Schramm, Andreas

Titel

Genomic insights into the Agromyces-like symbiont of earthworms and its distribution among host species

Ist Teil von

• FEMS microbiology ecology, 2018-06, Vol.94 (6), p.1

Ort / Verlag

England: Oxford University Press

Erscheinungsjahr

2018

Link zum Volltext

Quelle

Free E-Journal (出版社公開部分のみ）

Beschreibungen/Notizen

• Abstract The nephridia (excretory organs) of lumbricid earthworms generally harbor symbiotic bacteria. In the compost worms Eisenia fetida and E. andrei, these comprise Verminephrobacter, Ca. Nephrothrix and an Agromyces-like symbiont. While diversity, transmission, and function of the first two symbionts has been unraveled in recent years, little is known about the biology of the uncultured Agromyces-like symbiont or about its distribution within lumbricid earthworms. In this study, we sequenced a cocoon metagenome of E. andrei and assembled a 96.3% complete genome of the Agromyces-like symbiont, which indicates a heterotrophic and potentially microaerophilic lifestyle. A 16S rRNA gene based survey showed that the Agromyces-like symbiont has a narrow host range (present in 10 out of 51 investigated lumbricid earthworm species) and is likely species-specific or at least specific for groups of closely related host species. The Agromyces-like symbionts form a monophyletic group and feature a reduced genome with AT-bias and very low genome-wide similarity to closely related Agromyces spp. (average amino acid identity of 64%); therefore, we suggest establishing a novel genus for the Agromyces-like symbionts of earthworms, for which we propose the name Candidatus Lumbricidophila, with the specific symbiont of Eisenia andrei as novel species Ca. L. eiseniae. The first genome of a member of the uncultivated Candidatus Lumbricidophila genus, an earthworm symbiont present in approximately 20% of investigated Lumbricid earthworms, is sequenced.