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Pyridoxal Phosphate Enzymes
Pyridoxal (PL) is one form of vitamin B6. Some medically relevant bacteria, such as those in the genera '' Granulicatella'' and '' Abiotrophia'', require pyridoxal for growth. This nutritional requirement can lead to the culture phenomenon of satellite growth. In ''in vitro'' culture, these pyridoxal-dependent bacteria may only grow in areas surrounding colonies of bacteria from other genera ("satellitism") that are capable of producing pyridoxal. Pyridoxal is involved in what is believed to be the most ancient reaction of aerobic metabolism on Earth, about 2.9 billion years ago, a forerunner of the Great Oxidation Event."Protein Domain Structure Uncovers the Origin of Aerobic Metabolism and the Rise of Planetary Oxygen", Gustavo Caetano-Anolles et al., published in Structure; paper available from University of Illinois News Bureau, 2012. See also * Pyridoxal phosphate Pyridoxal phosphate (PLP, pyridoxal 5'-phosphate, P5P), the active form of vitamin B6, is a coenz ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pyridoxine
Pyridoxine (PN) is a form of vitamin B6 found commonly in food and used as a dietary supplement. As a supplement it is used to treat and prevent pyridoxine deficiency, sideroblastic anaemia, pyridoxine-dependent epilepsy, certain metabolic disorders, side effects or complications of isoniazid use, and certain types of mushroom poisoning. It is used by mouth or by injection. It is usually well tolerated. Occasionally side effects include headache, numbness, and sleepiness. Normal doses are safe during pregnancy and breastfeeding. Pyridoxine is in the vitamin B family of vitamins. It is required by the body to metabolise amino acids, carbohydrates, and lipids. Sources in the diet include meat, fish, fruit, vegetables, and grain. Medical uses As a treatment (oral or injection), it is used to treat or prevent pyridoxine deficiency, sideroblastic anaemia, pyridoxine-dependent epilepsy, certain metabolic disorders, side effects of isoniazid treatment and certain types ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Damnacanthal
Damnacanthal is an anthraquinone isolated from the root of ''Morinda citrifolia'', using water or organic solvents. Pharmacology In a 1995 in vitro study, damnacanthal was found to act as a potent and selective inhibitor of p56lck tyrosine kinase A tyrosine kinase is an enzyme that can transfer a phosphate group from ATP to the tyrosine residues of specific proteins inside a cell. It functions as an "on" or "off" switch in many cellular functions. Tyrosine kinases belong to a larger cla .... References Hydroxyanthraquinones Tyrosine kinase inhibitors Conjugated aldehydes Phenol ethers {{aromatic-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aldehydes
In organic chemistry, an aldehyde () (lat. ''al''cohol ''dehyd''rogenatum, dehydrogenated alcohol) is an organic compound containing a functional group with the structure . The functional group itself (without the "R" side chain) can be referred to as an aldehyde but can also be classified as a formyl group. Aldehydes are a common motif in many chemicals important in technology and biology. Structure and bonding Aldehyde molecules have a central carbon atom that is connected by a double bond to oxygen, a single bond to hydrogen and another single bond to a third substituent, which is carbon or, in the case of formaldehyde, hydrogen. The central carbon is often described as being sp2- hybridized. The aldehyde group is somewhat polar. The bond length is about 120–122 picometers. Physical properties and characterization Aldehydes have properties that are diverse and that depend on the remainder of the molecule. Smaller aldehydes such as formaldehyde and acetaldehyde are soluble ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vitamins
Vitamins are organic molecules (or a set of closely related molecules called vitamers) that are essential to an organism in small quantities for proper metabolic function. Essential nutrients cannot be synthesized in the organism in sufficient quantities for survival, and therefore must be obtained through the diet. For example, vitamin C can be synthesized by some species but not by others; it is not considered a vitamin in the first instance but is in the second. Most vitamins are not single molecules, but groups of related molecules called vitamers. For example, there are eight vitamers of vitamin E: four tocopherols and four tocotrienols. The term ''vitamin'' does not include the three other groups of essential nutrients: minerals, essential fatty acids, and essential amino acids. Major health organizations list thirteen vitamins: * Vitamin A (all-''trans''- retinols, all-''trans''-retinyl-esters, as well as all-''trans''- β-carotene and other provitamin A c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pyridoxal Phosphate
Pyridoxal phosphate (PLP, pyridoxal 5'-phosphate, P5P), the active form of vitamin B6, is a coenzyme in a variety of enzymatic reactions. The International Union of Biochemistry and Molecular Biology has catalogued more than 140 PLP-dependent activities, corresponding to ~4% of all classified activities. The versatility of PLP arises from its ability to covalently bind the substrate, and then to act as an electrophilic catalyst, thereby stabilizing different types of carbanionic reaction intermediates. Role as a coenzyme PLP acts as a coenzyme in all transamination reactions, and in certain decarboxylation, deamination, and racemization reactions of amino acids. The aldehyde group of PLP forms a Schiff-base linkage (internal aldimine) with the ε-amino group of a specific lysine group of the aminotransferase enzyme. The α-amino group of the amino acid substrate displaces the ε-amino group of the active-site lysine residue in a process known as transaldimination. The r ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Great Oxidation Event
The Great Oxidation Event (GOE) or Great Oxygenation Event, also called the Oxygen Catastrophe, Oxygen Revolution, Oxygen Crisis or Oxygen Holocaust, was a time interval during the Earth's Paleoproterozoic era when the Earth's atmosphere and shallow seas first experienced a rise in the concentration of free oxygen. This began approximately 2.460–2.426 billion years ago (Ga) during the Siderian period and ended approximately 2.060 Ga ago during the Rhyacian. Geological, isotopic and chemical evidence suggests that biologically produced molecular oxygen (dioxygen or O2) started to accumulate in the Archean prebiotic atmosphere due to microbial photosynthesis, and eventually changed it from a weakly reducing atmosphere practically devoid of oxygen into an oxidizing one containing abundant free oxygen, with oxygen levels being as high as 10% of modern atmospheric level by the end of the GOE. The appearance of highly reactive free oxygen, which can oxidize o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Abiotrophia
''Abiotrophia'' is a genus of lactic acid bacteria, a family in the phylum Bacillota (Bacteria). Species The genus contains 4 species of coccus shaped species, 2 are former members of the genus ''Streptococcus'', which were transferred in 1995 to the newly coined genus ''Abiotrophia'': * '' A. adiacens'' ( (Bouvet ''et'' ''al''. 1989) Kawamura ''et'' ''al''. 1995; Latin feminine gender adjective ''adiacens'', adjacent, indicating that this organism can grow as satellite colonies adjacent to other bacterial growth.) * '' A. defectiva'' ( (Bouvet ''et'' ''al''. 1989) Kawamura ''et'' ''al''. 1995, comb. nov. (Type species of the genus).; Latin feminine gender adjective ''defectiva'', deficient.) Other 2 are latter additions: * '' A. balaenopterae'' ( Lawson ''et'' ''al''. 1999; Neo-Latin genitive case noun ''balaenopterae'', pertaining to the minke whale, ''Balaenoptera acutorostrata'', from which the organism was isolated.) * '' A. elegans'' ( Roggenkamp ''et'' ''al''. 1999; Latin f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Granulicatella
''Granulicatella'' is a genus of bacteria from the family of Carnobacteriaceae. These bacteria occurs in the upper respiratory tract, in the gastrointestinal tract, and the urogenital tract The genitourinary system, or urogenital system, are the sex organs of the reproductive system and the organ (biology), organs of the urinary system. These are grouped together because of their proximity to each other, Development of the urinary a .... ''Granulicatella'' bacteria can cause disease in humans in rare cases. References Lactobacillales Taxa described in 2000 {{Firmicutes-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vitamin B6
Vitamin B6 is one of the B vitamins, and is an essential nutrient for humans. The term essential nutrient refers to a group of six chemically similar compounds, i.e., "vitamers", which can be interconverted in biological systems. Its active form, pyridoxal phosphate, pyridoxal 5′-phosphate, serves as a coenzyme in more than 140 enzyme reactions in amino acid, glucose, and lipid metabolism. Plants synthesize pyridoxine as a means of protection from the UV-B, UV-B radiation found in sunlight and for the role it plays in the synthesis of chlorophyll. Animals cannot synthesize any of the various forms of the vitamin, and hence must obtain it via diet, either of plants, or of other animals. There is some absorption of the vitamin produced by intestinal bacteria, but this is not sufficient to meet dietary needs. For adult humans, recommendations from various countries' food regulatory agencies are in the range of 1.0 to 2.0 milligrams (mg) per day. These same agencies also recogni ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gossypol
Gossypol () is a natural phenol derived from the cotton plant (genus ''Gossypium''). Gossypol is a phenolic aldehyde that permeates cells and acts as an inhibitor for several dehydrogenase enzymes. It is a yellow pigment. The structure exhibits atropisomerism, with the two enantiomers having different biochemical properties. Among other applications, it has been tested as a male oral contraceptive in China. In addition to its putative contraceptive properties, gossypol has also long been known to possess antimalarial properties. History Utilization of cotton-seed oil in the 19th century was complicated by the fact that it stained everything. In 1882-1883 James Longmore from Liverpool took several patents on separating the colorant by partial saponification of the oil, and in 1886 he presented his findings to the local section of the Society of Chemical Industry. He is often considered the discoverer of gossypol, even though he only isolated it in crude form. The name was co ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hemiacetal
In organic chemistry, a hemiacetal is a functional group the general formula , where is a hydrogen atom or an organic substituent. They generally result from the nucleophilic Addition reaction, addition of an Alcohol (chemistry), alcohol (a compound with at least one hydroxy group) to an aldehyde () or a ketone () under acidic conditions. The addition of an alcohol to a ketone is more commonly referred to as a hemiketal. Common examples of hemiacetals include cyclic Monosaccharide, monosaccharides. Hemiacetals have use as a protecting group and in synthesizing oxygenated heterocycles like Tetrahydrofuran, tetrahydrofurans. Nomenclature According to the IUPAC definition of a hemiacetal, the R1 and R2 groups may or may not be hydrogen. In a hemiketal, both of these R-groups must not be hydrogen. Thus, hemiketals are regarded as a subclass of hemiacetals. The prefix ''hemi,'' meaning half, refers to the one alcohol added to the carbonyl group. This is half of the required alcohols to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
