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Proteobacteria
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. This rena ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Betaproteobacteria
''Betaproteobacteria'' are a class of Gram-negative bacteria, and one of the six classes of the phylum '' Pseudomonadota'' (synonym Proteobacteria). Metabolism The ''Betaproteobacteria'' comprise over 75 genera and 400 species. Together, they represent a broad variety of metabolic strategies and occupy diverse environments, ranging from obligate pathogens living within host organisms to oligotrophic groundwater ecosystems. Whilst most members of the ''Betaproteobacteria'' are heterotrophic, deriving both their carbon and electrons from organocarbon sources, some are photoheterotrophic, deriving energy from light and carbon from organocarbon sources. Other genera are autotrophic, deriving their carbon from bicarbonate or carbon dioxide and their electrons from reduced inorganic ions such as nitrite, ammonium, thiosulfate or sulfide — many of these chemolithoautotrophic. ''Betaproteobacteria'' are economically important, with roles in maintaining soil pH and in elementa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alphaproteobacteria
''Alphaproteobacteria'' or ''α-proteobacteria'', also called ''α-Purple bacteria'' in earlier literature, is a class of bacteria in the phylum '' Pseudomonadota'' (formerly "Proteobacteria"). The '' Magnetococcales'' and '' Mariprofundales'' are considered basal or sister to the ''Alphaproteobacteria''. The ''Alphaproteobacteria'' are highly diverse and possess few commonalities, but nevertheless share a common ancestor. Like all ''Proteobacteria'', its members are gram-negative, although some of its intracellular parasitic members lack peptidoglycan and are consequently gram variable. Characteristics The ''Alphaproteobacteria'' are a diverse taxon and comprise several phototrophic genera, several genera metabolising C1-compounds (e.g. ''Methylobacterium'' spp.), symbionts of plants (e.g. '' Rhizobium'' spp.), endosymbionts of arthropods ('' Wolbachia'') and intracellular pathogens (e.g. '' Rickettsia''). Moreover, the class is sister to the protomitochondrion, the bacterium ... [...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] |
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] |
Hydrogenophilalia
The ''Hydrogenophilaceae'' are a family of the class '' Hydrogenophilalia'' in the phylum ''Pseudomonadota'' ("Proteobacteria"), with two genera – '' Hydrogenophilus'' and '' Tepidiphilus''. Like all ''Pseudomonadota'', they are Gram-negative. All known species are thermophilic, growing around 50 °C, and use molecular hydrogen or organic molecules as their source of electrons to support growth; some species are autotrophs. The genus ''Thiobacillus'' was previously considered to be a member in this family but was reclassified into the order ''Nitrosomonadales'' at the same time that the '' Hydrogenophilales'' were removed from the ''Betaproteobacteria'' to form the class '' Hydrogenophilalia''. '' Hydrogenophilus thermoluteolus'' is a facultative chemolithoautotroph originally isolated from a hot spring; however, it was detected 2004 in ice core samples retrieved from a depth around 3 km within the ice covering Lake Vostok in Antarctica. The presence of DNA from (and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Acidithiobacillia
''Acidithiobacillia'' is a class of the phylum '' Pseudomonadota'' ("Proteobacteria"). Its type order, the ''Acidithiobacillales'', was formerly classified within the '' Gammaproteobacteria'', and comprises two families of sulfur-oxidising autotrophs, the ''Acidithiobacillaceae'' and the '' Thermithiobacillaceae'', which in turn include the genera ''Acidithiobacillus ''Acidithiobacillus'' is a genus of the '' Acidithiobacillia'' in the phylum "'' Pseudomonadota''". This genus includes ten species of acidophilic microorganisms capable of sulfur and/or iron oxidation: ''Acidithiobacillus albertensis, Acidithiob ...'' and '' Thermithiobacillus''. Acidithiobacilia is part of the acidophilic bacteria family. Acidithiobacilia's metabolic activity is important because it is relied on for a approach for metal recovery from ores, called microorganism-mediated biohydrometallurgy. Acidithiobacilia and family of bacteria are active players in the sulfur and iron biogeochemical cycles in e ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hydrogenophilaceae
The ''Hydrogenophilaceae'' are a family of the class '' Hydrogenophilalia'' in the phylum ''Pseudomonadota'' ("Proteobacteria"), with two genera – '' Hydrogenophilus'' and '' Tepidiphilus''. Like all ''Pseudomonadota'', they are Gram-negative. All known species are thermophilic, growing around 50 °C, and use molecular hydrogen or organic molecules as their source of electrons to support growth; some species are autotrophs. The genus ''Thiobacillus'' was previously considered to be a member in this family but was reclassified into the order ''Nitrosomonadales'' at the same time that the '' Hydrogenophilales'' were removed from the ''Betaproteobacteria'' to form the class '' Hydrogenophilalia''. '' Hydrogenophilus thermoluteolus'' is a facultative chemolithoautotroph originally isolated from a hot spring; however, it was detected 2004 in ice core samples retrieved from a depth around 3 km within the ice covering Lake Vostok in Antarctica. The presence of DNA from (and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thermodesulfobacteriota
The Thermodesulfobacteriota, or Desulfobacterota, are a phylum of anaerobic Gram-negative bacteria. Many representatives are sulfate-reducing bacteria, others can grow by disproportionation of various sulphur species, reduction or iron, or even use external surfaces as electron acceptors ( exoelectrogens). They have highly variable morphology: vibrio, rods, cocci, as well as filamentous cable bacteria. Individual members of Desulfobacterota are also studied for their bacterial nanowires or syntrophic relationships. Taxonomy The bacterial phylum Desulfobacterota has been created by merging: 1) the well-established class Thermodesulfobacteria, 2) the proposed phylum Dadabacteria, and 3) various taxa separated from the abandoned non-monophyletic class "Deltaproteobacteria" alongside three other phyla: Myxococcota, Bdellovibrionota, and SAR324. Environment In contrast to their close relatives, the aerobic phyla Myxococcota and Bdellovibrionota, Desulfobacterota are predom ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nitrogen Fixation
Nitrogen fixation is a chemical process by which molecular dinitrogen () is converted into ammonia (). It occurs both biologically and abiological nitrogen fixation, abiologically in chemical industry, chemical industries. Biological nitrogen fixation or ''diazotrophy'' is catalyzed by enzymes called nitrogenases. These enzyme complexes are encoded by the Nif gene, ''Nif'' genes (or ''Nif'' homologs) and contain iron, often with a second metal (usually molybdenum, but sometimes vanadium). Some nitrogen-fixing bacteria have symbiotic relationships with plants, especially legumes, mosses and aquatic ferns such as ''Azolla''. Looser non-symbiotic relationships between diazotrophs and plants are often referred to as associative, as seen in nitrogen fixation on rice roots. Nitrogen fixation occurs between some termites and fungus, fungi. It occurs naturally in the air by means of NOx, NOx production by lightning. Fixed nitrogen is essential to life on Earth. Organic compounds such ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oligoflexia
The Oligoflexia are a class of the phylum Bdellovibrionota. All species of this group are all Gram-negative Gram-negative bacteria are bacteria that, unlike gram-positive bacteria, do not retain the crystal violet stain used in the Gram staining method of bacterial differentiation. Their defining characteristic is that their cell envelope consists .... References Gram-negative bacteria {{Bacteria-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Desulfobacterota
The Thermodesulfobacteriota, or Desulfobacterota, are a phylum of anaerobic Gram-negative bacteria. Many representatives are sulfate-reducing bacteria, others can grow by disproportionation of various sulphur species, reduction or iron, or even use external surfaces as electron acceptors ( exoelectrogens). They have highly variable morphology: vibrio, rods, cocci, as well as filamentous cable bacteria. Individual members of Desulfobacterota are also studied for their bacterial nanowires or syntrophic relationships. Taxonomy The bacterial phylum Desulfobacterota has been created by merging: 1) the well-established class Thermodesulfobacteria, 2) the proposed phylum Dadabacteria, and 3) various taxa separated from the abandoned non-monophyletic class "Deltaproteobacteria" alongside three other phyla: Myxococcota, Bdellovibrionota, and SAR324. Environment In contrast to their close relatives, the aerobic phyla Myxococcota and Bdellovibrionota, Desulfobacterota are predom ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
International Committee On Systematics Of Prokaryotes
The International Committee on Systematics of Prokaryotes (ICSP), formerly the International Committee on Systematic Bacteriology (ICSB), is the body that oversees the nomenclature of prokaryotes, determines the rules by which prokaryotes are named and whose Judicial Commission issues Opinions concerning taxonomic matters, revisions to the Bacteriological Code, etc. Composition The ICSP consists of an executive board, the members of a decision-making committee (judicial commission) and members elected from member societies of the International Union of Microbiological Societies (IUMS). In addition, the ICSP has a number of subcommittees dealing with issues regarding the nomenclature and taxonomy of specific groups of prokaryotes. Subcommittees The ICSP has a number of subcommittees dealing with issues regarding the nomenclature and taxonomy of specific groups of prokaryotes. These include the following: *''Aeromonadaceae, Vibrionaceae'' and related organisms *Genera ''Agroba ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
