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Verrucomicrobiota
Verrucomicrobiota is a phylum of Gram-negative bacteria that contains only a few described species. The species identified have been isolated from fresh water, marine and soil environments and human faeces. A number of as-yet uncultivated species have been identified in association with eukaryotic hosts including extrusive explosive ectosymbionts of protists and endosymbionts of nematodes residing in their gametes. Verrucomicrobiota are abundant within the environment, though relatively inactive. This phylum is considered to have two sister phyla: Chlamydiota (formerly Chlamydiae) and Lentisphaerota (formerly Lentisphaerae) within the PVC superphylum. The Verrucomicrobiota phylum can be distinguished from neighbouring phyla within the PVC group by the presence of several conserved signature indels (CSIs). These CSIs represent unique, synapomorphic characteristics that suggest common ancestry within Verrucomicrobiota and an independent lineage amidst other bacteria. CSIs hav ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
PVC Superphylum
The PVC superphylum is a superphylum of bacteria named after its three important members, Planctomycetota, Verrucomicrobiota, and Chlamydiota. Cavalier-Smith postulated that the PVC bacteria probably lost or reduced their peptidoglycan cell wall twice. It has been hypothesised that a member of the PVC clade might have been the host cell in the endosymbiotic event that gave rise to the first proto-eukaryotic cell. Cavalier-Smith calls the same group Planctobacteria and considers it a phylum. However, this is not followed by the larger scientific community. In the Cavalier-Smith bacterial megaclassification, it is within the bacterial Gracilicutes infra-kingdom and comprises the phyla Chlamydiota, Lentisphaerota, Planctomycetota, Verrucomicrobiota. Molecular signatures Planctomycetota, Verrucomicrobiota, and Chlamydiota in the traditional molecular phylogeny view are considered as phyla and also cluster together in the PVC superphylum, along with the candidate phyla Omnit ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Planctobacteria
The PVC superphylum is a superphylum of bacteria named after its three important members, Planctomycetota, Verrucomicrobiota, and Chlamydiota. Cavalier-Smith postulated that the PVC bacteria probably lost or reduced their peptidoglycan cell wall twice. It has been hypothesised that a member of the PVC clade might have been the host cell in the endosymbiotic event that gave rise to the first proto-eukaryotic cell. Cavalier-Smith calls the same group Planctobacteria and considers it a phylum. However, this is not followed by the larger scientific community. In the Cavalier-Smith bacterial megaclassification, it is within the bacterial Gracilicutes infra-kingdom and comprises the phyla Chlamydiota, Lentisphaerota, Planctomycetota, Verrucomicrobiota. Molecular signatures Planctomycetota, Verrucomicrobiota, and Chlamydiota in the traditional molecular phylogeny view are considered as phyla and also cluster together in the PVC superphylum, along with the candidate phyla Omnitrophic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Methylacidiphilum Infernorum
''Methylacidiphilum infernorum '' is an extremely acidophilic methanotrophic aerobic bacteria first isolated and described in 2007 growing on soil and sediment on Hell's Gate, New Zealand. Similar organisms have also been isolated from geothermal sites on Italy and Russia. A polyextremophile, these non-motile rods grows optimally at pH between 2.0 and 2.5 and temperature of 60 °C. It is a methanotrophic obligated bacteria that grows at 25% (v/v) of methane in air. It is also very dependent on carbon dioxide concentrations to grow, optimally at 8% (v/v) in air. Due to its classification in the phylum ''Verrucomicrobiota'' and its extreme acidophilic phenotype ''M. infernorum'' is unique between all known methanotrophs. Biology Genome It has a single circular chromosome of 2,287,145 base pairs. Under genome analysis it was found that ''M. infernorum'' may use a novel methylotrophic pathway because it encodes methane monooxygenase enzymes but lacks known genetic modu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Opitutae
The Opitutales is an order in the phylum Verrucomicrobiota Verrucomicrobiota is a phylum of Gram-negative bacteria that contains only a few described species. The species identified have been isolated from fresh water, marine and soil environments and human faeces. A number of as-yet uncultivated speci .... References Verrucomicrobiota Bacteria orders {{Bacteria-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
The All-Species Living Tree Project
The All-Species Living Tree' Project is a collaboration between various academic groups/institutes, such as ARB, SILVA rRNA database project, and LPSN, with the aim of assembling a database of 16S rRNA sequences of all validly published species of ''Bacteria'' and ''Archaea''. At one stage, 23S sequences were also collected, but this has since stopped. Currently there are over 10,950 species in the aligned dataset and several more are being added either as new species are discovered or species that are not represented in the database are sequenced. Initially the latter group consisted of 7% of species. Similar (and more recent) projects include the Genomic Encyclopedia of Bacteria and Archaea (GEBA), which focused on whole genome sequencing of bacteria and archaea. Tree The tree was created by maximum likelihood analysis without bootstrap: consequently accuracy is traded off for size and many phylum level clades are not correctly resolved (such as the Firmicutes). (Eukaryote ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gram-negative Bacteria
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 wall sandwiched between an inner cytoplasmic cell membrane and a bacterial outer membrane. Gram-negative bacteria are found in virtually all environments on Earth that support life. The gram-negative bacteria include the model organism ''Escherichia coli'', as well as many pathogenic bacteria, such as ''Pseudomonas aeruginosa'', '' Chlamydia trachomatis'', and ''Yersinia pestis''. They are a significant medical challenge as their outer membrane protects them from many antibiotics (including penicillin), detergents that would normally damage the inner cell membrane, and lysozyme, an antimicrobial enzyme produced by animals that forms part of the innate immune system. Additionally, the outer leaflet of this membrane comprises a complex lipopol ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chlamydiota
The Chlamydiota (synonym Chlamydiae) are a bacterial phylum and class whose members are remarkably diverse, including pathogens of humans and animals, symbionts of ubiquitous protozoa, and marine sediment forms not yet well understood. All of the Chlamydiota that humans have known about for many decades are obligate intracellular bacteria; in 2020 many additional Chlamydiota were discovered in ocean-floor environments, and it is not yet known whether they all have hosts. Historically it was believed that all Chlamydiota had a peptidoglycan-free cell wall, but studies in the 2010s demonstrated a detectable presence of peptidoglycan, as well as other important proteins. Among the Chlamydiota, all of the ones long known to science grow only by infecting eukaryotic host cells. They are as small as or smaller than many viruses. They are ovoid in shape and stain Gram-negative. They are dependent on replication inside the host cells; thus, some species are termed obligate intrace ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lentisphaerota
Lentisphaerota is a phylum of bacteria closely related to Chlamydiota and Verrucomicrobiota. It includes two monotypic orders Lentisphaerales and Victivallales. Phylum members can be aerobic or anaerobic and fall under two distinct phenotypes. These phenotypes live within bodies of sea water and were particularly hard to isolate in a pure culture. One phenotype, ''L. marina'', consists of terrestrial gut microbiota from mammals and birds. It was found in the Sea of Japan. The other phenotype (''L. araneosa'') includes marine microorganisms: sequences from fish and coral microbiomes and marine sediment. Phylogeny The phylogeny based on the work of the All-Species Living Tree Project. Taxonomy The currently accepted taxonomy is based on the List of Prokaryotic names with Standing in Nomenclature (LSPN) and the National Center for Biotechnology Information (NCBI). * Phylum Lentisphaerota Cho et al. 2021 ** Class Oligosphaeria Qiu et al. 2013 *** Order Oligosphaerales ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pseudomonadota
Pseudomonadota (synonym Proteobacteria) is a major phylum of Gram-negative bacteria. The renaming of phyla in 2021 remains controversial among microbiologists, many of whom continue to use the earlier names of long standing in the literature. The phylum Proteobacteria includes a wide variety of pathogenic genera, such as '' Escherichia'', '' Salmonella'', '' Vibrio'', '' Yersinia'', '' Legionella'', and many others.Slonczewski JL, Foster JW, Foster E. Microbiology: An Evolving Science 5th Ed. WW Norton & Company; 2020. Others are free-living (non parasitic) and include many of the bacteria responsible for nitrogen fixation. Carl Woese established this grouping in 1987, calling it informally the "purple bacteria and their relatives". Because of the great diversity of forms found in this group, it was later informally named Proteobacteria, after Proteus, a Greek god of the sea capable of assuming many different shapes (not after the Proteobacteria genus ''Proteus''). In 2021 the I ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Homology (biology)
In biology, homology is similarity due to shared ancestry between a pair of structures or genes in different taxa. A common example of homologous structures is the forelimbs of vertebrates, where the wings of bats and birds, the arms of primates, the front flippers of whales and the forelegs of four-legged vertebrates like dogs and crocodiles are all derived from the same ancestral tetrapod structure. Evolutionary biology explains homologous structures adapted to different purposes as the result of descent with modification from a common ancestor. The term was first applied to biology in a non-evolutionary context by the anatomist Richard Owen in 1843. Homology was later explained by Charles Darwin's theory of evolution in 1859, but had been observed before this, from Aristotle onwards, and it was explicitly analysed by Pierre Belon in 1555. In developmental biology, organs that developed in the embryo in the same manner and from similar origins, such as from matching prim ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chromosome
A chromosome is a long DNA molecule with part or all of the genetic material of an organism. In most chromosomes the very long thin DNA fibers are coated with packaging proteins; in eukaryotic cells the most important of these proteins are the histones. These proteins, aided by chaperone proteins, bind to and condense the DNA molecule to maintain its integrity. These chromosomes display a complex three-dimensional structure, which plays a significant role in transcriptional regulation. Chromosomes are normally visible under a light microscope only during the metaphase of cell division (where all chromosomes are aligned in the center of the cell in their condensed form). Before this happens, each chromosome is duplicated ( S phase), and both copies are joined by a centromere, resulting either in an X-shaped structure (pictured above), if the centromere is located equatorially, or a two-arm structure, if the centromere is located distally. The joined copies are now c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Base Pair
A base pair (bp) is a fundamental unit of double-stranded nucleic acids consisting of two nucleobases bound to each other by hydrogen bonds. They form the building blocks of the DNA double helix and contribute to the folded structure of both DNA and RNA. Dictated by specific hydrogen bonding patterns, "Watson–Crick" (or "Watson–Crick–Franklin") base pairs (guanine–cytosine and adenine–thymine) allow the DNA helix to maintain a regular helical structure that is subtly dependent on its nucleotide sequence. The complementary nature of this based-paired structure provides a redundant copy of the genetic information encoded within each strand of DNA. The regular structure and data redundancy provided by the DNA double helix make DNA well suited to the storage of genetic information, while base-pairing between DNA and incoming nucleotides provides the mechanism through which DNA polymerase replicates DNA and RNA polymerase transcribes DNA into RNA. Many DNA-binding prot ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
