Thermosphaera

Thermosphaera is a genus of the Desulfurococcaceae. They are a group of prokaryotic organisms which have been discovered in extremely hot environments such as sulfur springs, volcanoes, and magma pools. Isolates of Thermosphaera were first identified in 1998 from the Obsidian Pool in Yellowstone National Park.

Thermosphaera
Scientific classification
Domain:	Archaea
Kingdom:	Proteoarchaeota
Superphylum:	TACK group
Phylum:	Thermoproteota
Class:	Thermoprotei
Order:	Desulfurococcales
Family:	Desulfurococcaceae
Genus:	Thermosphaera Huber et al. 1998
Species:	T. aggregans
Binomial name
Thermosphaera aggregans Huber et al. 1998

Cell structure and metabolism

Cells of Thermosphaera are cocci (spherical) and form grape-like aggregates during the exponential growth phase. In the late exponential and stationary growth phases, smaller groups, including some single cells, were visible. Aggregates were shown to have several flagella; single cells could have as many as eight. The cell envelope is an amorphous layer covering a cytoplasmic membrane. Temperatures exceeding 92 °C inhibits growth, as does sulfur and hydrogen. Thermosphaera cells are heterotrophic, processing energy from yeast.

Ecology

Thermosphaera are found mainly in sulfuric pools, where they thrive on the extreme temperatures. In terms of research and economic significance, learning more about these organisms and their properties may help advancements in biotechnology.

Genome structure

Sequencing the 16S rRNA of Thermosphaera showed that this isolate was a member of the group Crenarchaeota and closely related to Staphylothermus and Desulfurococcus.

See also

• List of Archaea genera

Further reading

• Huber R; Dyba D; Huber H; Burggraf S; Rachel R (1998). "Sulfur-inhibited Thermosphaera aggregans sp. nov., a new genus of hyperthermophilic archaea isolated after its prediction from environmentally derived 16S rRNA sequences". Int. J. Syst. Bacteriol. 48: 31–38. doi:10.1099/00207713-48-1-31. PMID 9542073.
• Burggraf S; Huber H; Stetter KO (1997). "Reclassification of the crenarchael orders and families in accordance with 16S rRNA sequence data". Int. J. Syst. Bacteriol. 47 (3): 657–660. doi:10.1099/00207713-47-3-657. PMID 9226896.
• Huber R; Burggraf S; Mayer T; Barns SM; Rossnagel P; Stetter KO (1995). "Isolation of a hyperthermophilic archaeum predicted by in situ RNA analysis". Nature. 376 (6535): 57–58. Bibcode:1995Natur.376...57H. doi:10.1038/376057a0. PMID 7541115. S2CID 4335718.
• Zillig W; Stetter KO; Prangishvilli D; Schafer W; Wunderl S; Janekovic D; et al. (1982). "Desulfurococcaceae, the second family of the extremely thermophilic, anaerobic, sulfur-respiring Thermoproteales". Zentralbl. Bakteriol. Parasitenkd. Infektionskr. Hyg. Abt. 1 Orig. C3: 304–317.