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Bacillati
Bacillati, formerly known as Terrabacteria, is a kingdom containing approximately two-thirds of prokaryote species, including those in the gram positive phyla (Actinomycetota and Bacillota) as well as the phyla Cyanobacteriota, Chloroflexota, and Deinococcota. It derives its name (''terra'' = "land") from the evolutionary pressures of life on land. Bacillati possess important adaptations such as resistance to environmental hazards (e.g., desiccation, ultraviolet radiation, and high salinity) and oxygenic photosynthesis. Also, the unique properties of the cell wall in gram-positive taxa, which likely evolved in response to terrestrial conditions, have contributed toward pathogenicity in many species. These results now leave open the possibility that terrestrial adaptations may have played a larger role in prokaryote evolution than currently understood. "Terrabacteria" (syn. Bacillati) was proposed in 2004 for Actinomycetota, Cyanobacteriota, and Deinococcota and was expanded late ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hydrobacteria
Hydrobacteria is a taxon containing approximately one-third of prokaryote species, mostly gram-negative bacteria and their relatives. It was found to be the closest relative of an even larger group of Bacteria, Terrabacteria, which are mostly gram positive bacteria. The name Hydrobacteria (hydro = "water") refers to the moist environment inferred for the common ancestor of those species. In contrast, species of Terrabacteria possess adaptations for life on land. The content of Hydrobacteria has grown to include these superphyla and phyla: Acidobacteriota, Aquificota, Bdellovibrionota, Campylobacterota, Deferribacterota, Dependentiae, Desulfobacterota, Desulfuromonadota, Elusimicrobiota, FCB superphylum, Myxococcota, Nitrospirota, Proteobacteria, PVC superphylum, and Spirochaetota. Some unrooted molecular phylogenetic analyses have not supported this dichotomy of Terrabacteria and Hydrobacteria, but the most recent genomic analyses, including those that have focus ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Caldisericota
''Caldisericum exile'' is a species of bacteria sufficiently distinct from other bacteria to be placed in its own family, order, class and phylum In biology, a phylum (; plural: phyla) is a level of classification or taxonomic rank below kingdom and above class. Traditionally, in botany the term division has been used instead of phylum, although the International Code of Nomenclatu .... It is the first member of the thermophilic candidate phylum OP5 to be cultured and described. References External linksType strain of ''Caldisericum exile'' at Bac''Dive'' - the Bacterial Diversity Metadatabase Caldiserica Thermophiles Bacteria genera {{bacteria-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dictyoglomota
''Dictyoglomus'' is a genus of bacterium, given its own Phylum, called the Dictyoglomi. This organism is extremely ''thermophilic'', meaning it thrives at extremely high temperatures. It is ''chemoorganotrophic'', meaning it derives energy by metabolizing organic molecules. This organism is of interest because it elaborates an enzyme, xylanase, which digests xylan, a heteropolymer of the pentose sugar xylose. By pretreating wood pulp with this enzyme, paper manufacturers can achieve comparable levels of whiteness with much less chlorine bleach. It has been described as Gram-negative Gram-negative bacteria are bacteria that do not retain the crystal violet stain used in the Gram staining method of bacterial differentiation. They are characterized by their cell envelopes, which are composed of a thin peptidoglycan cell wa ..., with a triple-layered wall. References Further reading * * External linksType strain of ''Dictyoglomus thermophilum'' at Bac''Dive'' - the Ba ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Atribacterota
''Atribacterota'' is a phylum of bacteria, which are common in anoxic sediments rich in methane. They are distributed worldwide and in some cases abundant in anaerobic marine sediments, geothermal springs, and oil deposits. Genetic analyzes suggest a heterotrophic metabolism that gives rise to fermentation products such as acetate An acetate is a salt (chemistry), salt formed by the combination of acetic acid with a base (e.g. Alkali metal, alkaline, Alkaline earth metal, earthy, Transition metal, metallic, nonmetallic or radical Radical (chemistry), base). "Acetate" als ..., ethanol, and . These products in turn can support methanogens within the sediment microbial community and explain the frequent occurrence of Atribacterota in methane-rich anoxic sediments. According to phylogenetic analysis, Atribacterota appears to be related to several thermophilic phyla within Terrabacteria or may be in the base of Gracilicutes. According to research, Atribacterota shows pa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Coprothermobacterota
''Coprothermobacterota'' is a phylum of nonmotile, rod-shaped bacteria. Its members are strictly anaerobic and thermophilic, growing at optimal temperatures between 55 °C and 70 °C. The name of this phylum is based on an early genus, dubbed "'' Coprothermobacter''", a term whose etymology derives from the Greek words "''kopros''", meaning manure, and "''thermos''", warm, referring to the fact that these bacteria are capable of living at relatively high temperatures, with a maximum growth temperature of 75 °C. Notes In October 2021, the name of this phylum has been accepted as ''validly published'', according to the emendations of the rules of the International Code of Nomenclature of Prokaryotes The International Code of Nomenclature of Prokaryotes (ICNP) formerly the International Code of Nomenclature of Bacteria (ICNB) or Bacteriological Code (BC) governs the scientific names for Bacteria and Archaea.P. H. A. Sneath, 2003. A short hist ... proposed to in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Synergistota
The Synergistota is a phylum of anaerobic bacteria that show Gram-negative staining and have rod/vibrioid cell shape. Although Synergistota have a diderm cell envelope,Gupta, R. S. (2011) Origin of Diderm (Gram-negative) Bacteria: Antibiotic Selection Pressure Rather than Endosymbiosis Likely led to the Evolution of Bacterial Cells with Two Membranes. Antonie van Leeuwenhoek. 100: 171–182 the genes for various proteins involved in lipopolysaccharides biosynthesis have not yet been detected in Synergistota, indicating that they may have an atypical outer cell envelope. The Synergistota inhabit a majority of anaerobic environments including animal gastrointestinal tracts, soil, oil wells, and wastewater treatment plants and they are also present in sites of human diseases such as cysts, abscesses, and areas of periodontal disease.Vartoukian, S.R., Palmer, R.M., and Wade, W.G. (2007). The division "Synergistes". Anaerobe. 13, 99–106. Due to their presence at illness related site ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fusobacteriota
Fusobacteriota are obligately anaerobic non-sporeforming Gram-negative bacilli. Since the first reports in the late nineteenth century, various names have been applied to these organisms, sometimes with the same name being applied to different species. More recently, not only have there been changes to the nomenclature, but also attempts to differentiate between species which are believed to be either pathogenic or commensal or both. Because of their asaccharolytic nature, and a general paucity of positive results in routine biochemical tests, laboratory identification of the Fusobacteriota has been difficult. However, the application of novel molecular biological techniques to taxonomy has established a number of new species, together with the subspeciation of ''Fusobacterium necrophorum'' and ''F. nucleatum'', and provided new methods for identification. The involvement of Fusobacteriota in a wide spectrum of human infections causing tissue necrosis and septicaemia has long bee ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
DST Group
Daylight saving time (DST), also referred to as daylight savings time or simply daylight time (United States, Canada, and Australia), and summer time (United Kingdom, European Union, and others), is the practice of advancing clocks (typically by one hour) during warmer months so that darkness falls at a later clock time. The typical implementation of DST is to set clocks forward by one hour in the spring ("spring forward"), and to set clocks back by one hour in the fall (" fall back") to return to standard time. As a result, there is one 23-hour day in early spring and one 25-hour day in the middle of autumn. The idea of aligning waking hours to daylight hours to conserve candles was first proposed in 1784 by U.S. polymath Benjamin Franklin. In a satirical letter to the editor of ''The Journal of Paris'', Franklin suggested that waking up earlier in the summer would economize on candle usage; and calculated considerable savings. In 1895, New Zealand entomologist and astronome ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Timeline Of Life
The timeline of the evolutionary history of life represents the current scientific theory outlining the major events during the development of life on planet Earth. Dates in this article are consensus estimates based on scientific evidence, mainly fossils. In biology, evolution is any change across successive generations in the heritable characteristics of biological populations. Evolutionary processes give rise to diversity at every level of biological organization, from kingdoms to species, and individual organisms and molecules, such as DNA and proteins. The similarities between all present day organisms imply a common ancestor from which all known species, living and extinct, have diverged. More than 99 percent of all species that ever lived (over five billion) are estimated to be extinct. Estimates on the number of Earth's current species range from 10 million to 14 million, with about 1.2 million or 14% documented, the rest not yet described. However, a 2016 report estima ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Molecular Clock
The molecular clock is a figurative term for a technique that uses the mutation rate of biomolecules to deduce the time in prehistory when two or more life forms diverged. The biomolecular data used for such calculations are usually nucleotide sequences for DNA, RNA, or amino acid sequences for proteins. The benchmarks for determining the mutation rate are often fossil or archaeological dates. The molecular clock was first tested in 1962 on the hemoglobin protein variants of various animals, and is commonly used in molecular evolution to estimate times of speciation or radiation. It is sometimes called a gene clock or an evolutionary clock. Early discovery and genetic equidistance The notion of the existence of a so-called "molecular clock" was first attributed to Émile Zuckerkandl and Linus Pauling who, in 1962, noticed that the number of amino acid differences in hemoglobin between different lineages changes roughly linearly with time, as estimated from fossil ev ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
