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Zetaproteobacteria
The class Zetaproteobacteria is the sixth and most recently described class of the Pseudomonadota. Zetaproteobacteria can also refer to the group of organisms assigned to this class. The Zetaproteobacteria were originally represented by a single described species, '' Mariprofundus ferrooxydans'', which is an iron-oxidizing neutrophilic chemolithoautotroph originally isolated from Kamaʻehuakanaloa Seamount (formerly Loihi) in 1996 (post-eruption). Molecular cloning techniques focusing on the small subunit ribosomal RNA gene have also been used to identify a more diverse majority of the Zetaproteobacteria that have as yet been unculturable. Regardless of culturing status, the Zetaproteobacteria show up worldwide in estuarine and marine habitats associated with opposing steep redox gradients of reduced (ferrous) iron and oxygen, either as a minor detectable component or as the dominant member of the microbial community. Zetaproteobacteria have been most commonly found at deep- ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pseudomonadota
Pseudomonadota (synonym "Proteobacteria") is a major phylum of gram-negative bacteria. Currently, they are considered the predominant phylum within the domain of bacteria. They are naturally found as pathogenic and free-living (non- parasitic) genera. The phylum comprises six classes ''Acidithiobacillia, Alphaproteobacteria, Betaproteobacteria, Gammaproteobacteria, Hydrogenophilia'', and '' Zetaproteobacteria.'' The Pseudomonadota are widely diverse, with differences in morphology, metabolic processes, relevance to humans, and ecological influence. Classification American microbiologist Carl Woese established this grouping in 1987, calling it informally the "purple bacteria and their relatives". The group was later formally named the 'Proteobacteria' after the Greek god Proteus, who was known to assume many forms. In 2021 the International Committee on Systematics of Prokaryotes designated the synonym Pseudomonadota, and renamed many other prokaryotic phyla as well. Th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mariprofundus
''Mariprofundus ferrooxydans'' is a neutrophilic, chemolithotrophic, Gram-negative bacterium which can grow by oxidising ferrous to ferric iron. It is one of the few members of the class Zetaproteobacteria in the phylum Pseudomonadota. It is typically found in iron-rich deep sea environments, particularly at hydrothermal vents. ''M. ferrooxydans'' characteristically produces stalks of solid iron oxyhydroxides that form into iron mats. Genes that have been proposed to catalyze Fe(II) oxidation in ''M. ferrooxydans'' are similar to those involved in known metal redox pathways, and thus it serves as a good candidate for a model iron oxidizing organism. Discovery The bacterium was isolated from iron-rich microbial mats associated with hydrothermal vents at a submarine volcano, Kamaʻehuakanaloa Seamount (formerly Lōʻihi), near Hawaii Hawaii ( ; ) is an island U.S. state, state of the United States, in the Pacific Ocean about southwest of the U.S. mainland. One of the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mariprofundus Ferrooxydans
''Mariprofundus ferrooxydans'' is a neutrophilic, chemolithotrophic, Gram-negative bacterium which can grow by oxidising ferrous to ferric iron. It is one of the few members of the class Zetaproteobacteria in the phylum Pseudomonadota. It is typically found in iron-rich deep sea environments, particularly at hydrothermal vents. ''M. ferrooxydans'' characteristically produces stalks of solid iron oxyhydroxides that form into iron mats. Genes that have been proposed to catalyze Fe(II) oxidation in ''M. ferrooxydans'' are similar to those involved in known metal redox pathways, and thus it serves as a good candidate for a model iron oxidizing organism. Discovery The bacterium was isolated from iron-rich microbial mats associated with hydrothermal vents at a submarine volcano, Kamaʻehuakanaloa Seamount (formerly Lōʻihi), near Hawaii Hawaii ( ; ) is an island U.S. state, state of the United States, in the Pacific Ocean about southwest of the U.S. mainland. One ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kamaʻehuakanaloa Seamount
Kamaʻehuakanaloa Seamount (previously known as Lōʻihi) is an active submarine volcano about off the southeast coast of the island of Hawaii. The top of the seamount is about below sea level. This seamount is on the flank of Mauna Loa, the largest active subaerial shield volcano on Earth. Kamaʻehuakanaloa is the newest volcano in the Hawaiian–Emperor seamount chain, a string of volcanoes that stretches about northwest of Kamaʻehuakanaloa. Unlike most active volcanoes in the Pacific Ocean that make up the active plate margins on the Pacific Ring of Fire, Kamaʻehuakanaloa and the other volcanoes of the Hawaiian–Emperor seamount chain are hotspot volcanoes and formed well away from the nearest plate boundary. Volcanoes in the Hawaiian Islands arise from the Hawaii hotspot, and as the youngest volcano in the chain, Kamaʻehuakanaloa is the only Hawaiian volcano in the deep submarine preshield stage of development. Kamaʻehuakanaloa began forming around 400,000 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chemolithotrophic
Lithotrophs are a diverse group of organisms using an inorganic substrate (usually of mineral origin) to obtain reducing equivalents for use in biosynthesis (e.g., carbon dioxide fixation) or energy conservation (i.e., ATP production) via aerobic or anaerobic respiration. While lithotrophs in the broader sense include photolithotrophs like plants, chemolithotrophs are exclusively microorganisms; no known macrofauna possesses the ability to use inorganic compounds as electron sources. Macrofauna and lithotrophs can form symbiotic relationships, in which case the lithotrophs are called "prokaryotic symbionts". An example of this is chemolithotrophic bacteria in giant tube worms or plastids, which are organelles within plant cells that may have evolved from photolithotrophic cyanobacteria-like organisms. Chemolithotrophs belong to the domains Bacteria and Archaea. The term "lithotroph" was created from the Greek terms 'lithos' (rock) and 'troph' (consumer), meaning "eaters of r ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gammaproteobacteria
''Gammaproteobacteria'' is a class of bacteria in the phylum ''Pseudomonadota'' (synonym ''Proteobacteria''). It contains about 250 genera, which makes it the most genus-rich taxon of the Prokaryotes. Several medically, ecologically, and scientifically important groups of bacteria belong to this class. All members of this class are Gram-negative. It is the most phylogenetically and physiologically diverse class of the ''Pseudomonadota''. Members of ''Gammaproteobacteria'' live in several terrestrial and marine environments, in which they play various important roles, including in extreme environments such as hydrothermal vents. They can have different shapes, rods, curved rods, cocci, spirilla, and filaments, and include free living bacteria, biofilm formers, commensals and symbionts; some also have the distinctive trait of being bioluminescent. Diverse metabolisms are found in ''Gammaproteobacteria''; there are both aerobic and anaerobic (obligate or facultative) species, chem ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Iron(III) Oxide-hydroxide
Iron(III) oxide-hydroxide or ferric oxyhydroxideA. L. Mackay (1960): "β-Ferric Oxyhydroxide". ''Mineralogical Magazine'' (''Journal of the Mineralogical Society''), volume 32, issue 250, pages 545-557. is the chemical compound of iron, oxygen, and hydrogen with formula . The compound is often encountered as one of its hydrates, ·''n'' (rust). The monohydrate · is often referred to as iron(III) hydroxide , hydrated iron oxide, yellow iron oxide, or Pigment Yellow 42. Natural occurrences Minerals Anhydrous ferric hydroxide occurs in the nature as the exceedingly rare mineral bernalite, Fe(OH)3·''n''H2O (''n'' = 0.0–0.25). Iron oxyhydroxides, , are much more common and occur naturally as structurally different minerals (polymorphs) denoted by the Greek letters α, β, γ and δ. * Goethite, α-FeO(OH), has been used as an ochre pigment since prehistoric times. * Akaganeite is the β polymorph,A. L. Mackay (1962): "β-Ferric oxyhydroxide—akaganéite", ''Mineralogi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ferric
In chemistry, iron(III) or ''ferric'' refers to the chemical element, element iron in its +3 oxidation number, oxidation state. ''Ferric chloride'' is an alternative name for iron(III) chloride (). The adjective ''ferrous'' is used instead for iron(II) salts, containing the cation Fe2+. The word ''wikt:ferric, ferric'' is derived from the Latin word , meaning "iron". Although often abbreviated as Fe3+, that naked ion does not exist except under extreme conditions. Iron(III) centres are found in many compounds and coordination complexes, where Fe(III) is bonded to several Ligand, ligands. A molecular ferric complex is the anion ferrioxalate, , with three bidentate oxalate ions surrounding the Fe core. Relative to lower oxidation states, ferric is less common in organoiron chemistry, but the ferrocenium cation is well known. Iron(III) in biology All known forms of life require iron, which usually exists in Fe(II) or Fe(III) oxidation states. Many proteins in living beings cont ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bacteria
Bacteria (; : bacterium) are ubiquitous, mostly free-living organisms often consisting of one Cell (biology), biological cell. They constitute a large domain (biology), domain of Prokaryote, prokaryotic microorganisms. Typically a few micrometres in length, bacteria were among the first life forms to appear on Earth, and are present in most of its habitats. Bacteria inhabit the air, soil, water, Hot spring, acidic hot springs, radioactive waste, and the deep biosphere of Earth's crust. Bacteria play a vital role in many stages of the nutrient cycle by recycling nutrients and the nitrogen fixation, fixation of nitrogen from the Earth's atmosphere, atmosphere. The nutrient cycle includes the decomposition of cadaver, dead bodies; bacteria are responsible for the putrefaction stage in this process. In the biological communities surrounding hydrothermal vents and cold seeps, extremophile bacteria provide the nutrients needed to sustain life by converting dissolved compounds, suc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
