''Pyrodictium'' is a

genus Genus (; : genera ) is a taxonomic rank above species and below family (taxonomy), family as used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In bino ...

in the family Pyrodictiaceae. It is a genus of submarine hyperthermophilic

Archaea Archaea ( ) is a Domain (biology), domain of organisms. Traditionally, Archaea only included its Prokaryote, prokaryotic members, but this has since been found to be paraphyletic, as eukaryotes are known to have evolved from archaea. Even thou ...

whose optimal growth

temperature Temperature is a physical quantity that quantitatively expresses the attribute of hotness or coldness. Temperature is measurement, measured with a thermometer. It reflects the average kinetic energy of the vibrating and colliding atoms making ...

range is 80 to 110°C. They have a unique cell structure involving a network of cannulae and flat, disk-shaped cells. ''Pyrodictium'' are found in the porous walls of deep-sea vents where the temperatures inside get as high as 400°C, while the outside marine environment is typically 3°C. ''Pyrodictium'' is apparently able to adapt morphologically to this type of hot–cold habitat.

Genome structure

Much research has been done on the genetics of ''Pyrodictium'' in order to understand its ability to survive and even thrive in such extreme temperatures. The thermal stability of ''Pyrodictum occultums isolate tRNA has been analyzed, indicating that modifications in the nucleosides allow the organism to withstand temperatures well over 100°C.

Cell structure and metabolism

''Pyrodictium'' cells have been studied by scientists, in part because they are a model of thermal stability. The cells' structure is a flat, irregular disk, 300 to 2500 nanometres in diameter and up to 300 nanometres in width. The cells grow in unique flake-like shapes held together by a network of hollow cannulae (tubules). The cannulae branch out and connect with other cells, greatly extending their range. While the exact reason for this morphology is unknown, it is likely that the range of motion provided by the cannulae allow the cells to move freely when by the thermal energy from the extreme heat of the organisms's environment. The large size range of the cells may allow ''Pyrodictium'' to inhabit a variety of pores in the deep-sea vent walls.

Ecology

Members of ''Pyrodictium'' are located in deep-sea hydrothermal vents, first discovered in 1979. Their ecological significance remains a mystery because of the difficulty in collecting samples which may yield data on the abundance and diversity of these extremophiles.

Phylogeny

The currently accepted taxonomy is based on the

List of Prokaryotic names with Standing in Nomenclature List of Prokaryotic names with Standing in Nomenclature (LPSN) is an online database that maintains information on the naming and taxonomy of prokaryotes, following the taxonomy requirements and rulings of the International Code of Nomenclatu ...

(LPSN) and

National Center for Biotechnology Information The National Center for Biotechnology Information (NCBI) is part of the National Library of Medicine (NLM), a branch of the National Institutes of Health (NIH). It is approved and funded by the government of the United States. The NCBI is lo ...

(NCBI)

References

External links

Archaea genera Thermoproteota {{archaea-stub

Genome structure

Cell structure and metabolism

Ecology

Phylogeny

See also

References

Further reading

Scientific journals

External links