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Illudin S
The illudins are a family of sesquiterpenes with antitumor antibiotic properties produced by some mushrooms. In their isolated form, illudins show selective toxicity for myelocytic leukemia and other carcinoma cells. Illudins are highly toxic, with little apparent therapeutic value in their natural form. Illudins are thought to be responsible for the toxicity of various ''Omphalotus'' species such as '' O. olearius'' and '' O. illudens'' (Jack o' Lantern mushrooms), and '' O. nidiformis'' (Australian ghost fungus). Active metabolites of illudins damage DNA via an unknown mechanism. In addition, genetic analysis suggests that the illudin-mediated DNA damage is ignored by global excision repair systems unless the lesions occur within stalled replication or transcription Transcription refers to the process of converting sounds (voice, music etc.) into letters or musical notes, or producing a copy of something in another medium, including: Genetics * Transcription (biology), the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Illudin Family
The illudins are a family of sesquiterpenes with antitumor antibiotic properties produced by some mushrooms. In their isolated form, illudins show selective toxicity for myelocytic leukemia and other carcinoma cells. Illudins are highly toxic, with little apparent therapeutic value in their natural form. Illudins are thought to be responsible for the toxicity of various ''Omphalotus'' species such as '' O. olearius'' and '' O. illudens'' (Jack o' Lantern mushrooms), and '' O. nidiformis'' (Australian ghost fungus). Active metabolites of illudins damage DNA via an unknown mechanism. In addition, genetic analysis suggests that the illudin-mediated DNA damage is ignored by global excision repair systems unless the lesions occur within stalled replication or transcription Transcription refers to the process of converting sounds (voice, music etc.) into letters or musical notes, or producing a copy of something in another medium, including: Genetics * Transcription (biology), the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Omphalotus Nidiformis
''Omphalotus nidiformis'', or ghost fungus, is a gilled basidiomycete mushroom most notable for its bioluminescent properties. It is known to be found primarily in southern Australia and Tasmania, but was reported from India in 2012 and 2018. The fan or funnel shaped fruit bodies are up to across, with cream-coloured caps overlain with shades of orange, brown, purple, or bluish-black. The white or cream gills run down the length of the stipe, which is up to long and tapers in thickness to the base. The fungus is both saprotrophic and parasitic, and its fruit bodies are generally found growing in overlapping clusters on a wide variety of dead or dying trees. First described scientifically in 1844, the fungus has been known by several names in its taxonomic history. It was assigned its current name by Orson K. Miller, Jr. in 1994. Its epithet name is derived from the Latin ''nidus'' "nest", hence 'nest shaped'. Similar in appearance to the common edible oyster mushroom, it ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Spiro Compounds
In organic chemistry, spiro compounds are compounds that have at least two molecular rings with only one common atom. The simplest spiro compounds are bicyclic (having just two rings), or have a bicyclic portion as part of the larger ring system, in either case with the two rings connected through the defining single common atom. The one common atom connecting the participating rings distinguishes spiro compounds from other bicyclics: from ''isolated ring compounds'' like biphenyl that have no connecting atoms, from ''fused ring compounds'' like decalin having two rings linked by two adjacent atoms, and from ''bridged ring compounds'' like norbornane with two rings linked by two non-adjacent atoms.For all four categories, see The specific chapters can be found aan respectively, same access date. For the description featuring adjacent atoms for all but the isolated category, see Clayden, op. cit. Spiro compounds may be fully carbocyclic (all carbon) or heterocyclic (havi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tertiary Alcohols
In chemistry, an alcohol is a type of organic compound that carries at least one hydroxyl () functional group bound to a saturated carbon atom. The term ''alcohol'' originally referred to the primary alcohol ethanol (ethyl alcohol), which is used as a drug and is the main alcohol present in alcoholic drinks. An important class of alcohols, of which methanol and ethanol are the simplest examples, includes all compounds which conform to the general formula . Simple monoalcohols that are the subject of this article include primary (), secondary () and tertiary () alcohols. The suffix ''-ol'' appears in the IUPAC chemical name of all substances where the hydroxyl group is the functional group with the highest priority. When a higher priority group is present in the compound, the prefix ''hydroxy-'' is used in its IUPAC name. The suffix ''-ol'' in non-IUPAC names (such as paracetamol or cholesterol) also typically indicates that the substance is an alcohol. However, some compound ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Terpenes And Terpenoids
Terpenes () are a class of natural products consisting of compounds with the formula (C5H8)n for n > 1. Comprising more than 30,000 compounds, these unsaturated hydrocarbons are produced predominantly by plants, particularly conifers. Terpenes are further classified by the number of carbons: monoterpenes (C10), sesquiterpenes (C15), diterpenes (C20), as examples. The terpene alpha-pinene, is a major component of the common solvent, turpentine. History and terminology The term ''terpene'' was coined in 1866 by the German chemist August Kekulé to denote all hydrocarbons having the empirical formula C10H16, of which camphene was one. Previously, many hydrocarbons having the empirical formula C10H16 had been called "camphene", but many other hydrocarbons of the same composition had had different names. Kekulé coined the term "terpene" in order to reduce the confusion. The name "terpene" is a shortened form of "terpentine", an obsolete spelling of "turpentine". Although sometimes u ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Transcription (biology)
Transcription is the process of copying a segment of DNA into RNA. The segments of DNA transcribed into RNA molecules that can encode proteins are said to produce messenger RNA (mRNA). Other segments of DNA are copied into RNA molecules called non-coding RNAs (ncRNAs). mRNA comprises only 1–3% of total RNA samples. Less than 2% of the human genome can be transcribed into mRNA ( Human genome#Coding vs. noncoding DNA), while at least 80% of mammalian genomic DNA can be actively transcribed (in one or more types of cells), with the majority of this 80% considered to be ncRNA. Both DNA and RNA are nucleic acids, which use base pairs of nucleotides as a complementary language. During transcription, a DNA sequence is read by an RNA polymerase, which produces a complementary, antiparallel RNA strand called a primary transcript. Transcription proceeds in the following general steps: # RNA polymerase, together with one or more general transcription factors, binds to promoter ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
DNA Replication
In molecular biology, DNA replication is the biological process of producing two identical replicas of DNA from one original DNA molecule. DNA replication occurs in all living organisms acting as the most essential part for biological inheritance. This is essential for cell division during growth and repair of damaged tissues, while it also ensures that each of the new cells receives its own copy of the DNA. The cell possesses the distinctive property of division, which makes replication of DNA essential. DNA is made up of a double helix of two complementary strands. The double helix describes the appearance of a double-stranded DNA which is thus composed of two linear strands that run opposite to each other and twist together to form. During replication, these strands are separated. Each strand of the original DNA molecule then serves as a template for the production of its counterpart, a process referred to as semiconservative replication. As a result of semi-conservative rep ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nucleotide Excision Repair
Nucleotide excision repair is a DNA repair mechanism. DNA damage occurs constantly because of chemicals (e.g. intercalating agents), radiation and other mutagens. Three excision repair pathways exist to repair single stranded DNA damage: Nucleotide excision repair (NER), base excision repair (BER), and DNA mismatch repair (MMR). While the BER pathway can recognize specific non-bulky lesions in DNA, it can correct only damaged bases that are removed by specific glycosylases. Similarly, the MMR pathway only targets mismatched Watson-Crick base pairs. Nucleotide excision repair (NER) is a particularly important excision mechanism that removes DNA damage induced by ultraviolet light (UV). UV DNA damage results in bulky DNA adducts - these adducts are mostly thymine dimers and 6,4-photoproducts. Recognition of the damage leads to removal of a short single-stranded DNA segment that contains the lesion. The undamaged single-stranded DNA remains and DNA polymerase uses it as a templa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Omphalotus Illudens
''Omphalotus illudens'', commonly known as the eastern jack-o'lantern mushroom, is a large, orange mushroom that is often found in clumps on decaying stumps, buried roots, or at the base of hardwood trees in eastern North America. Its gills often exhibit a weak green bioluminescence when fresh. This green glow has been mentioned in several journal articles, which state that the phenomenon can persist up to 40-50 hours after the mushroom has been picked. It is believed that this display serves to attract insects to the mushroom’s gills during nighttime, which can then distribute its spores across a wider area. ''Omphalotus illudens'' is sometimes confused with edible chanterelles, but can be distinguished by its thicker, fleshier appearance, tendency to form large clusters, and clearly separated caps when young. Unlike chanterelles, the Eastern Jack-o’-lantern is poisonous to humans when eaten, whether raw or cooked, and typically causes vomiting, cramps, and diarrhea. Altho ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sesquiterpene
Sesquiterpenes are a class of terpenes that consist of three isoprene units and often have the molecular formula C15H24. Like monoterpenes, sesquiterpenes may be cyclic or contain rings, including many unique combinations. Biochemical modifications such as oxidation or rearrangement produce the related sesquiterpenoids. Sesquiterpenes are found naturally in plants and insects, as semiochemicals, e.g. defensive agents or pheromones. Biosynthesis and examples The reaction of geranyl pyrophosphate with isopentenyl pyrophosphate results in the 15-carbon farnesyl pyrophosphate (FPP), which is an intermediate in the biosynthesis of sesquiterpenes such as farnesene. Cyclic sesquiterpenes are more common than cyclic monoterpenes because of the increased chain length and additional double bond in the sesquiterpene precursors. In addition to common six-membered ring systems such as the ones found in zingiberene and bisacurone, cyclization of one end of the chain to the other end can l ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Omphalotus Olearius
''Omphalotus olearius'',Singer R (1948) In: ''Pap. Mich. Acad. Sci.'' 32: 133 ('1946'). commonly known as the jack-o'-lantern mushroom, is a poisonous Orange (color), orange gilled mushroom that to an untrained eye appears similar to some Cantharellus, chanterelles. It is notable for its bioluminescence, bioluminescent properties. It is found in woodland areas in Europe, where it grows on decaying stumps, on buried roots or at the base of hardwood trees. It has also been reported from the Western Cape, Western Cape Province, South Africa. A similar, but phylogenetically distinct species found in eastern North America is ''Omphalotus illudens''. Unlike chanterelles, ''Omphalotus olearius'' and other ''Omphalotus'' species contain the toxin illudin S, and are poisonous to humans. While not lethal, consuming this mushroom leads to very severe cramps, vomiting, and diarrhea. Description The jack-o'-lantern mushroom is orange. Its bioluminescence, a blue-green color, can be observ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
