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α-proteobacterium
''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 that w ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
SAR11 Clade
The Pelagibacterales are an order in the Alphaproteobacteria composed of free-living marine bacteria that make up roughly one in three cells at the ocean's surface. Overall, members of the ''Pelagibacterales'' are estimated to make up between a quarter and a half of all prokaryotic cells in the ocean. Initially, this taxon was known solely by metagenomic data and was known as the SAR11 clade. It was first placed in the Rickettsiales, but was later raised to the rank of order, and then placed as sister order to the Rickettsiales in the subclass Rickettsidae. It includes the highly abundant marine species ''Pelagibacter ubique''. Bacteria in this order are unusually small. Due to their small genome size and limited metabolic function, ''Pelagibacterales'' have become a model organism for ' streamlining theory'. ''P. ubique'' and related species are oligotrophs (scavengers) and feed on dissolved organic carbon and nitrogen. They are unable to fix carbon or nitrogen, but can perfo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wolbachia
''Wolbachia'' is a genus of gram-negative bacteria infecting many species of arthropods and filarial nematodes. The symbiotic relationship ranges from parasitism to obligate mutualism. It is one of the most common parasitic microbes of arthropods, and is possibly the most widespread reproductive parasite bacterium in the biosphere. Its interactions with hosts are complex and highly diverse across different host species. Some host species cannot reproduce, or even survive, without ''Wolbachia'' colonisation. One study concluded that more than 16% of neotropical insect species carry bacteria of this genus, and as many as 25 to 70% of all insect species are estimated to be potential hosts. History The first organism classified as ''Wolbachia'' was discovered in 1924 by Marshall Hertig and Simeon Burt Wolbach in the common house mosquito. They described it as "a somewhat pleomorphic, rodlike, Gram-negative, intracellular organism hatapparently infects only the ovaries and te ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rhodothalassiales
__NOTOC__ ''Rhodothalassium'' is a genus of bacteria in the family Rhodobacteraceae The Rhodobacteraceae are a family of Pseudomonadota in the order Rhodobacterales within the alpha subgroup.See the NCBIbr>webpage on Rhodobacteraceae Data extracted from the Like all Pseudomonadota, they are gram-negative. It contains chem .... Up to now there is only one species of this genus known ('' Rhodothalassium salexigens''). References Further reading * Rhodobacteraceae Bacteria genera Monotypic bacteria genera {{Rhodobacterales-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Endosymbiont
An endosymbiont or endobiont is an organism that lives within the body or cells of another organism. Typically the two organisms are in a mutualism (biology), mutualistic relationship. Examples are nitrogen-fixing bacteria (called rhizobia), which live in the root nodules of legumes, single-cell algae inside Coral reef, reef-building corals, and bacterial endosymbionts that provide essential nutrients to insects. Endosymbiosis played key roles in the development of eukaryotes and plants. Roughly 2.2 billion years ago an archaeon absorbed a bacterium through phagocytosis, that eventually became the mitochondria that provide energy to almost all living Eukaryote, eukaryotic cells. Approximately 1 billion years ago, some of those cells absorbed cyanobacteria that eventually became chloroplasts, organelles that produce energy from sunlight. Approximately 100 million years ago, a lineage of amoeba in the genus ''Paulinella'' independently engulfed a cyanobacterium that evolved to be f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rhizobium
''Rhizobium'' is a genus of Gram-negative soil bacteria that fix nitrogen. ''Rhizobium'' species form an endosymbiotic nitrogen-fixing association with roots of (primarily) legumes and other flowering plants. The bacteria colonize plant cells to form root nodules, where they convert atmospheric nitrogen into ammonia using the enzyme nitrogenase. The ammonia is shared with the host plant in the form of organic nitrogenous compounds such as glutamine or ureides. The plant, in turn, provides the bacteria with organic compounds made by photosynthesis. This mutually beneficial relationship is true of all of the rhizobia, of which the genus ''Rhizobium'' is a typical example. ''Rhizobium'' is also capable of solubilizing phosphate. History Martinus Beijerinck was the first to isolate and cultivate a microorganism from the nodules of legumes in 1888. He named it ''Bacillus radicicola'', which is now placed in '' Bergey's Manual of Determinative Bacteriology'' under the gen ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phototroph
Phototrophs () are organisms that carry out photon capture to produce complex organic compounds (e.g. carbohydrates) and acquire energy. They use the energy from light to carry out various cellular metabolic processes. It is a list of common misconceptions, common misconception that phototrophs are obligatorily photosynthetic. Many, but not all, phototrophs often photosynthesize: they anabolism, anabolically convert carbon dioxide into organic material to be utilized structurally, functionally, or as a source for later catabolism, catabolic processes (e.g. in the form of starches, sugars and fats). All phototrophs either use electron transport chains or direct proton pumping to establish an electrochemical gradient which is utilized by ATP synthase, to provide the molecular energy currency for the cell. Phototrophs can be either autotrophs or heterotrophs. If their electron and hydrogen donors are inorganic compounds (e.g., , as in some purple sulfur bacteria, or , as in some gr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Peptidoglycan
Peptidoglycan or murein is a unique large macromolecule, a polysaccharide, consisting of sugars and amino acids that forms a mesh-like layer (sacculus) that surrounds the bacterial cytoplasmic membrane. The sugar component consists of alternating residues of β-(1,4) linked N-Acetylglucosamine, ''N''-acetylglucosamine (NAG) and N-Acetylmuramic acid, ''N''-acetylmuramic acid (NAM). Attached to the ''N''-acetylmuramic acid is an oligopeptide chain made of three to five amino acids. The peptide chain can be cross-linked to the peptide chain of another strand forming the 3D mesh-like layer. Peptidoglycan serves a structural role in the bacterial cell wall, giving structural strength, as well as counteracting the osmotic pressure of the cytoplasm. This repetitive linking results in a dense peptidoglycan layer which is critical for maintaining cell form and withstanding high osmotic pressures, and it is regularly replaced by peptidoglycan production. Peptidoglycan hydrolysis and synthesis ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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 of a thin peptidoglycan cell wall sandwiched between an inner ( cytoplasmic) membrane and an 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 antibiotics (including penicillin), detergents that would normally damage the inner cell membrane, and the antimicrobial enzyme lysozyme produced by animals as part of their innate immune system. Furthe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mariprofundales
''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 t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Magnetococcales
The Magnetococcales were an order of Alphaproteobacteria, but now the Mitochondrion, mitochondria are considered as sister to the alphaproteobactera, together forming the sister the marineproteo1 group, together forming the sister to Magnetococcidae. See also * List of bacterial orders * List of bacteria genera References Alphaproteobacteria Bacteria orders {{alphaproteobacteria-stub ... [...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] |
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] |
