|
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] |
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] |
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] |
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] |
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] |
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] |
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] |
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] |
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] |
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] |
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] |
Gram-negative Bacteria
Gram-negative bacteria are bacteria that, unlike gram-positive bacteria, do not retain the Crystal violet, crystal violet stain used in the Gram staining method of bacterial differentiation. Their defining characteristic is that their cell envelope consists of a thin peptidoglycan gram-negative cell wall, cell wall sandwiched between an inner (Cytoplasm, cytoplasmic) Cell membrane, membrane and an Bacterial outer membrane, outer membrane. These bacteria are found in all environments that support life on Earth. Within this category, notable species include the model organism ''Escherichia coli'', along with various pathogenic bacteria, such as ''Pseudomonas aeruginosa'', ''Chlamydia trachomatis'', and ''Yersinia pestis''. They pose significant challenges in the medical field due to their outer membrane, which acts as a protective barrier against numerous Antibiotic, antibiotics (including penicillin), Detergent, detergents that would normally damage the inner cell membrane, and the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phylum
In biology, a phylum (; : phyla) is a level of classification, or taxonomic rank, that is below Kingdom (biology), kingdom and above Class (biology), class. Traditionally, in botany the term division (taxonomy), division has been used instead of phylum, although the International Code of Nomenclature for algae, fungi, and plants accepts the terms as equivalent. Depending on definitions, the animal kingdom Animalia contains about 31 phyla, the plant kingdom Plantae contains about 14 phyla, and the fungus kingdom Fungi contains about eight phyla. Current research in phylogenetics is uncovering the relationships among phyla within larger clades like Ecdysozoa and Embryophyta. General description The term phylum was coined in 1866 by Ernst Haeckel from the Greek (, "race, stock"), related to (, "tribe, clan"). Haeckel noted that species constantly evolved into new species that seemed to retain few consistent features among themselves and therefore few features that distinguishe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
