Ferroglobus
Encyclopedia
In taxonomy
, Ferroglobus is a genus
of the Archaeoglobaceae
.
Ferroglobus is a hyperthermophilic
genus phylogenetically located within the Euryarchaeota
. It consists of one species, F. placidus, isolated from hydrothermal vent
sediment off the coast of Italy
. F. placidus grows best at 85°C and a neutral pH. It cannot grow at temperatures below 65°C or above 95°C. Cells possess an S-layer
cell wall and flagella.
Metabolically, Ferroglobus is quite unique compared to its relative Archaeoglobus
. F. placidus was the first hyperthermophile discovered to grow anaerobically by oxidizing aromatic compounds such as benzoate coupled to the reduction of ferric iron
(Fe3+) to ferrous iron
(Fe2+). Hydrogen
gas (H2) and sulfide
(H2S) can also be used as energy sources. Due to its anaerobic lifestyle, nitrate
(NO3-) is used as a terminal electron acceptor whereby it is converted to nitrite
(NO2-). Thiosulfate
(S2O32-) can also be used as a terminal electron acceptor. F. placidus was the first archaeon discovered that can anaerobically oxidize iron
coupled to the reduction of nitrate
. It is thought that the presence of organisms similar to F. placidus in the ancient, anoxic Earth may have led to the formation of banded iron formation
s often found in ancient rocks.
Alpha taxonomy
Alpha taxonomy is the discipline concerned with finding, describing and naming species of living or fossil organisms. This field is supported by institutions holding collections of these organisms, with relevant data, carefully curated: such institutes include natural history museums, herbaria and...
, Ferroglobus is a genus
Genus
In biology, a genus is a low-level taxonomic rank used in the biological classification of living and fossil organisms, which is an example of definition by genus and differentia...
of the Archaeoglobaceae
Archaeoglobaceae
In taxonomy, the Archaeoglobaceae are a family of the Archaeoglobales. All known genera within the Archaeoglobaceae are hyperthermophilic and can be found near undersea hydrothermal vents.- Mode of Metabolism :...
.
Ferroglobus is a hyperthermophilic
Hyperthermophile
A hyperthermophile is an organism that thrives in extremely hot environments— from 60 degrees C upwards. An optimal temperature for the existence of hyperthermophiles is above 80°C . Hyperthermophiles are a subset of extremophiles, micro-organisms within the domain Archaea, although some bacteria...
genus phylogenetically located within the Euryarchaeota
Euryarchaeota
In the taxonomy of microorganisms, the Euryarchaeota are a phylum of the Archaea.The Euryarchaeota include the methanogens, which produce methane and are often found in intestines, the halobacteria, which survive extreme concentrations of salt, and some extremely thermophilic aerobes and anaerobes...
. It consists of one species, F. placidus, isolated from hydrothermal vent
Hydrothermal vent
A hydrothermal vent is a fissure in a planet's surface from which geothermally heated water issues. Hydrothermal vents are commonly found near volcanically active places, areas where tectonic plates are moving apart, ocean basins, and hotspots. Hydrothermal vents exist because the earth is both...
sediment off the coast of Italy
Italy
Italy , officially the Italian Republic languages]] under the European Charter for Regional or Minority Languages. In each of these, Italy's official name is as follows:;;;;;;;;), is a unitary parliamentary republic in South-Central Europe. To the north it borders France, Switzerland, Austria and...
. F. placidus grows best at 85°C and a neutral pH. It cannot grow at temperatures below 65°C or above 95°C. Cells possess an S-layer
S-layer
An S-layer is a part of the cell envelope commonly found in bacteria, as well as among archaea.It consists of a monomolecular layer composed of identical proteins or glycoproteins. This two-dimensional structure is built via self-assembly and encloses the whole cell surface. Thus, the S-layer...
cell wall and flagella.
Metabolically, Ferroglobus is quite unique compared to its relative Archaeoglobus
Archaeoglobus
Archaeoglobus is a genus of the phylum Euryarchaeota. Archaeoglobus can be found in high-temperature oil fields where they may contribute to oil field souring.- Metabolism :...
. F. placidus was the first hyperthermophile discovered to grow anaerobically by oxidizing aromatic compounds such as benzoate coupled to the reduction of ferric iron
Iron
Iron is a chemical element with the symbol Fe and atomic number 26. It is a metal in the first transition series. It is the most common element forming the planet Earth as a whole, forming much of Earth's outer and inner core. It is the fourth most common element in the Earth's crust...
(Fe3+) to ferrous iron
Iron
Iron is a chemical element with the symbol Fe and atomic number 26. It is a metal in the first transition series. It is the most common element forming the planet Earth as a whole, forming much of Earth's outer and inner core. It is the fourth most common element in the Earth's crust...
(Fe2+). Hydrogen
Hydrogen
Hydrogen is the chemical element with atomic number 1. It is represented by the symbol H. With an average atomic weight of , hydrogen is the lightest and most abundant chemical element, constituting roughly 75% of the Universe's chemical elemental mass. Stars in the main sequence are mainly...
gas (H2) and sulfide
Sulfide
A sulfide is an anion of sulfur in its lowest oxidation state of 2-. Sulfide is also a slightly archaic term for thioethers, a common type of organosulfur compound that are well known for their bad odors.- Properties :...
(H2S) can also be used as energy sources. Due to its anaerobic lifestyle, nitrate
Nitrate
The nitrate ion is a polyatomic ion with the molecular formula NO and a molecular mass of 62.0049 g/mol. It is the conjugate base of nitric acid, consisting of one central nitrogen atom surrounded by three identically-bonded oxygen atoms in a trigonal planar arrangement. The nitrate ion carries a...
(NO3-) is used as a terminal electron acceptor whereby it is converted to nitrite
Nitrite
The nitrite ion has the chemical formula NO2−. The anion is symmetric with equal N-O bond lengths and a O-N-O bond angle of ca. 120°. On protonation the unstable weak acid nitrous acid is produced. Nitrite can be oxidised or reduced, with product somewhat dependent on the oxidizing/reducing agent...
(NO2-). Thiosulfate
Thiosulfate
Thiosulfate is an oxyanion of sulfur. The prefix thio indicates that thiosulfate ion is a sulfate ion with one oxygen replaced by a sulfur. Thiosulfate occurs naturally and is produced by certain biochemical processes...
(S2O32-) can also be used as a terminal electron acceptor. F. placidus was the first archaeon discovered that can anaerobically oxidize iron
Iron
Iron is a chemical element with the symbol Fe and atomic number 26. It is a metal in the first transition series. It is the most common element forming the planet Earth as a whole, forming much of Earth's outer and inner core. It is the fourth most common element in the Earth's crust...
coupled to the reduction of nitrate
Nitrate
The nitrate ion is a polyatomic ion with the molecular formula NO and a molecular mass of 62.0049 g/mol. It is the conjugate base of nitric acid, consisting of one central nitrogen atom surrounded by three identically-bonded oxygen atoms in a trigonal planar arrangement. The nitrate ion carries a...
. It is thought that the presence of organisms similar to F. placidus in the ancient, anoxic Earth may have led to the formation of banded iron formation
Banded iron formation
Banded iron formations are distinctive units of sedimentary rock that are almost always of Precambrian age. A typical BIF consists of repeated, thin layers of iron oxides, either magnetite or hematite , alternating with bands of iron-poor shale and chert...
s often found in ancient rocks.