Aquificae
Encyclopedia
The Aquificae phylum is a diverse collection of bacteria that live in harsh environmental settings. They have been found in hot springs, sulfur pools, and thermal ocean vents. Members of the genus Aquifex
, for example, are productive in water between 85 to 95 °C. They are the dominant members of most terrestrial neutral to alkaline hot springs above 60 degrees Celsius. They are autotrophs, and are the primary carbon fixers in these environments. They are true bacteria (domain
bacteria
) as opposed to the other inhabitants of extreme environments, the Archaea
.
, Calderobacterium, Hydrogenobacter, and Thermocrinis belong in the Aquificales order. Another claims that, in addition to genera within the Aquificaceae
and Hydrogenothermaceae
families, the following genera are incertae sedis
(unclassified), but within Aquificae: Balnearium, Desulfurobacterium, EX-H1 group, and Thermovibrio.
Cavalier-Smith has postulated that Aquificae is part of the Proteobacteria
.
Along with Thermotogae
, members of Aquificae are thermophilic eubacteria.
and the phylogeny is based on 16S rRNA-based LTP release 106 by The All-Species Living Tree Project
Note:
♠ Strain found at the National Center for Biotechnology Information
(NCBI) but not listed in the List of Prokaryotic names with Standing in Nomenclature (LPSN)
Aquifex
Aquifex is a genus of bacteria, one of the few in the phylum Aquificae. The two species generally classified in Aquifex are A. pyrophilus and A. aeolicus. Both are highly thermophilic, growing best in water temperature of 85 °C to 95 °C...
, for example, are productive in water between 85 to 95 °C. They are the dominant members of most terrestrial neutral to alkaline hot springs above 60 degrees Celsius. They are autotrophs, and are the primary carbon fixers in these environments. They are true bacteria (domain
Domain (biology)
In biological taxonomy, a domain is the highest taxonomic rank of organisms, higher than a kingdom. According to the three-domain system of Carl Woese, introduced in 1990, the Tree of Life consists of three domains: Archaea, Bacteria and Eukarya...
bacteria
Bacteria
Bacteria are a large domain of prokaryotic microorganisms. Typically a few micrometres in length, bacteria have a wide range of shapes, ranging from spheres to rods and spirals...
) as opposed to the other inhabitants of extreme environments, the Archaea
Archaea
The Archaea are a group of single-celled microorganisms. A single individual or species from this domain is called an archaeon...
.
Taxonomy
There is currently no consensus regarding the taxonomy of genera within Aquificae. One standard text claims that only the genera AquifexAquifex
Aquifex is a genus of bacteria, one of the few in the phylum Aquificae. The two species generally classified in Aquifex are A. pyrophilus and A. aeolicus. Both are highly thermophilic, growing best in water temperature of 85 °C to 95 °C...
, Calderobacterium, Hydrogenobacter, and Thermocrinis belong in the Aquificales order. Another claims that, in addition to genera within the Aquificaceae
Aquificaceae
The Aquificaceae family are bacteria that live in harsh environmental settings such as hot springs, sulfur pools, and hydrothermal vents. Although they are true bacteria as opposed to the other inhabitants of extreme environments, the Archaea, Aquificaceae genera are an early phylogenetic...
and Hydrogenothermaceae
Hydrogenothermaceae
The Hydrogenothermaceae family are bacteria that live in harsh environmental settings. They have been found in hot springs, sulfur pools, thermal ocean vents. They are true bacteria as opposed to the other inhabitants of extreme environments, the Archaea...
families, the following genera are incertae sedis
Incertae sedis
, is a term used to define a taxonomic group where its broader relationships are unknown or undefined. Uncertainty at specific taxonomic levels is attributed by , , and similar terms.-Examples:*The fossil plant Paradinandra suecica could not be assigned to any...
(unclassified), but within Aquificae: Balnearium, Desulfurobacterium, EX-H1 group, and Thermovibrio.
Cavalier-Smith has postulated that Aquificae is part of the Proteobacteria
Proteobacteria
The Proteobacteria are a major group of bacteria. They include a wide variety of pathogens, such as Escherichia, Salmonella, Vibrio, Helicobacter, and many other notable genera....
.
Along with Thermotogae
Thermotogae
Thermotogae is a phylum of the domain "Bacteria". This phylum comprises merely the class "Thermotogae", with the order "Thermotogales" and the family "Thermotogaceae"....
, members of Aquificae are thermophilic eubacteria.
Phylogeny
The currently accepted taxonomy is based on the List of Prokaryotic names with Standing in Nomenclature (LSPN)and the phylogeny is based on 16S rRNA-based LTP release 106 by The All-Species Living Tree Project
Note:
♠ Strain found at the National Center for Biotechnology Information
National Center for Biotechnology Information
The National Center for Biotechnology Information is part of the United States National Library of Medicine , a branch of the National Institutes of Health. The NCBI is located in Bethesda, Maryland and was founded in 1988 through legislation sponsored by Senator Claude Pepper...
(NCBI) but not listed in the List of Prokaryotic names with Standing in Nomenclature (LPSN)