A. aquaesulis The genus Annwoodia was named in 2017 to circumscribe an organism previously described as a member of the genus Thiobacillus, Thiobacillus aquaesulis - the type and only species is Annwoodia aquaesulis,[2] which was isolated from the geothermal waters of the Roman Baths in the city of Bath in the United Kingdom by Ann P. Wood and Donovan P. Kelly[3] of the University of Warwick - the genus was subsequently named to honour Wood's contribution to microbiology.
[2] The genus falls within the family Thiobacillaceae along with Thiobacillus and Sulfuritortus,[2][4] both of which comprise autotrophic organisms dependent on thiosulfate, other sulfur oxyanions and sulfide as electron donors for chemolithoheterotrophic growth.
[2] All members of the genus produce volutin (polyphosphate) granules but not capsules or endospores.
Annwoodia aquaesulis strains have been detected in mixed-population packed-bed reactors containing limestone as a source of carbon, elementary sulfur as the electron donor and nitrate as the terminal electron acceptor,[5] as well as in karstic sulfidic thermal groundwater ecosystems of broad similarity to those from which the type strain was isolated [6][7] Annwoodia aquaesulis grown on thiosulfate, tetrathionate or trithionate has high growth yields, which are broadly similar to those of Thermithiobacillus spp., and are higher than members of the closely related genus Thiobacillus, indicating core metabolic differences.
[2][3] This high yield was observed in spite of 70% more carbon dioxide being fixed than could be accounted for as biomass, indicating the excretion of a carbon intermediate, which is not observed in Thermithiobacillus tepidarius, which was isolated from the same location [3][8] at the Roman Baths in Bath, also by enrichment culture on thiosulfate as the sole electron donor and molecular oxygen as the terminal electron acceptor.