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Verrucomicrobia
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 Feces, 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, synapomorphy, synapomorphic characteristics that suggest common ancestry within Verrucomicrobiota and an independent lineage amidst other bact ... [...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 theory, 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 Bacterial phyla, traditional molecular phylogeny view are considered as phyla and also cluster together in the PVC superphylum, along ... [...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 modules ... [...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 intracellula ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Conserved Signature Indels
Conserved signature inserts and deletions (CSIs) in protein sequences provide an important category of molecular markers for understanding phylogenetic relationships. CSIs, brought about by rare genetic changes, provide useful phylogenetic markers that are generally of defined size and they are flanked on both sides by conserved regions to ensure their reliability. While indels can be arbitrary inserts or deletions, CSIs are defined as only those protein indels that are present within conserved regions of the protein. The CSIs that are restricted to a particular clade or group of species, generally provide good phylogenetic markers of common evolutionary descent. Due to the rarity and highly specific nature of such changes, it is less likely that they could arise independently by either convergent or parallel evolution (i.e. homoplasy) and therefore are likely to represent synapomorphy. Other confounding factors such as differences in evolutionary rates at different sites or among ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gracilicutes
Gracilicutes (Latin: ''gracilis'', slender, and ''cutis'', skin, referring to the cell wall) is a clade in bacterial phylogeny. Traditionally gram staining results were most commonly used as a classification tool, consequently until the advent of molecular phylogeny, the Kingdom Monera (as the domains Bacteria and Archaea were known then) was divided into four phyla, * Gracilicutes (gram-negative, it is split in many groups, but some authors still use it in a narrower sense) * Firmacutes ic(gram-positive, subsequently corrected to Firmicutes, today it excludes the Actinomycetota) * Mollicutes (gram variable, later renamed Tenericutes and now Mycoplasmatota, e.g. ''Mycoplasma'') * Mendosicutes (uneven gram stain, "methanogenic bacteria" now known as methanogens and classed as Archaea) This classification system was abandoned in favour of the three-domain system based on molecular phylogeny started by C. Woese. Using hand-drawn schematics rather than standard molecular phylogenet ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Conserved Signature Indels
Conserved signature inserts and deletions (CSIs) in protein sequences provide an important category of molecular markers for understanding phylogenetic relationships. CSIs, brought about by rare genetic changes, provide useful phylogenetic markers that are generally of defined size and they are flanked on both sides by conserved regions to ensure their reliability. While indels can be arbitrary inserts or deletions, CSIs are defined as only those protein indels that are present within conserved regions of the protein. The CSIs that are restricted to a particular clade or group of species, generally provide good phylogenetic markers of common evolutionary descent. Due to the rarity and highly specific nature of such changes, it is less likely that they could arise independently by either convergent or parallel evolution (i.e. homoplasy) and therefore are likely to represent synapomorphy. Other confounding factors such as differences in evolutionary rates at different sites or among ... [...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] |
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 Complementarity (molecular biology), 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 in ... [...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 called si ... [...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 p ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Clade
A clade (), also known as a monophyletic group or natural group, is a group of organisms that are monophyletic – that is, composed of a common ancestor and all its lineal descendants – on a phylogenetic tree. Rather than the English term, the equivalent Latin term ''cladus'' (plural ''cladi'') is often used in taxonomical literature. The common ancestor may be an individual, a population, or a species (extinct or extant). Clades are nested, one in another, as each branch in turn splits into smaller branches. These splits reflect evolutionary history as populations diverged and evolved independently. Clades are termed monophyletic (Greek: "one clan") groups. Over the last few decades, the cladistic approach has revolutionized biological classification and revealed surprising evolutionary relationships among organisms. Increasingly, taxonomists try to avoid naming taxa that are not clades; that is, taxa that are not monophyletic. Some of the relationships between organisms ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
