Misplaced Pages

#445554

79-457: Over 190 species, see LPSN Mycobacterium is a genus of over 190 species in the phylum Actinomycetota , assigned its own family, Mycobacteriaceae . This genus includes pathogens known to cause serious diseases in mammals, including tuberculosis ( M. tuberculosis ) and leprosy ( M. leprae ) in humans. The Greek prefix myco- means 'fungus', alluding to this genus' mold -like colony surfaces. Since this genus has cell walls with

158-557: A species : see Botanical name and Specific name (zoology) . The rules for the scientific names of organisms are laid down in the nomenclature codes , which allow each species a single unique name that, for animals (including protists ), plants (also including algae and fungi ) and prokaryotes ( bacteria and archaea ), is Latin and binomial in form; this contrasts with common or vernacular names , which are non-standardized, can be non-unique, and typically also vary by country and language of usage. Except for viruses ,

237-453: A dark background. Newer methods include Gomori-Methenamine Silver staining and Perioidic Acid Schiff staining to color Mycobacterium avium complex (MAC) cells black and pink, respectively. While some mycobacteria can take up to eight weeks to grow visible colonies from a cultured sample, most clinically relevant species will grow within the first four weeks, allowing physicians to consider alternative causes if negative readings continue past

316-756: A family of serine/threonine kinases that respond to a variety of extracellular growth signals. For example, growth hormone, epidermal growth factor, platelet-derived growth factor, and insulin are all considered mitogenic stimuli that can engage the MAPK pathway. Activation of this pathway at the level of the receptor initiates a signaling cascade whereby the Ras GTPase exchanges GDP for GTP . Next, Ras activates Raf kinase (also known as MAPKKK), which activates MEK (MAPKK). MEK activates MAPK (also known as ERK), which can go on to regulate transcription and translation . Whereas RAF and MAPK are both serine/threonine kinases, MAPKK

395-526: A general base and deprotonate the hydroxyl, as seen in the mechanism below. Here, a reaction between adenosine triphosphate (ATP) and phosphatidylinositol is coordinated. The end result is a phosphatidylinositol-3-phosphate as well as adenosine diphosphate (ADP) . The enzymes can also help to properly orient the ATP molecule, as well as the inositol group, to make the reaction proceed faster. Metal ions are often coordinated for this purpose. Sphingosine kinase (SK)

474-420: A large portion of the daily caloric requirement. To harvest energy from oligosaccharides , they must first be broken down into monosaccharides so they can enter metabolism . Kinases play an important role in almost all metabolic pathways. The figure on the left shows the second phase of glycolysis , which contains two important reactions catalyzed by kinases. The anhydride linkage in 1,3 bisphosphoglycerate

553-643: A later homonym of a validly published name is a nomen illegitimum or nom. illeg. ; for a full list refer to the International Code of Nomenclature for algae, fungi, and plants and the work cited above by Hawksworth, 2010. In place of the "valid taxon" in zoology, the nearest equivalent in botany is " correct name " or "current name" which can, again, differ or change with alternative taxonomic treatments or new information that results in previously accepted genera being combined or split. Prokaryote and virus codes of nomenclature also exist which serve as

632-621: A long time and redescribed as new by a range of subsequent workers, or if a range of genera previously considered separate taxa have subsequently been consolidated into one. For example, the World Register of Marine Species presently lists 8 genus-level synonyms for the sperm whale genus Physeter Linnaeus, 1758, and 13 for the bivalve genus Pecten O.F. Müller, 1776. Within the same kingdom, one generic name can apply to one genus only. However, many names have been assigned (usually unintentionally) to two or more different genera. For example,

711-427: A major role in cellular signalling , such as in the insulin signalling pathway, and also has roles in endocytosis , exocytosis and other trafficking events. Mutations in these kinases, such as PI3K, can lead to cancer or insulin resistance . The kinase enzymes increase the rate of the reactions by making the inositol hydroxyl group more nucleophilic, often using the side chain of an amino acid residue to act as

790-686: A multi-drug antibiotic treatment of isoniazid to inhibit mycolic acid synthesis, rifampicin to interfere with transcription, ethambutol to hinder arabinogalactan synthesis, and pyrazinamide to impede Coenzyme A synthesis. M. lepromatosis M. chelonae M. fortuitum M. flavescens M. smegmatis M. avium M. intracellulare M. kansasii M. scrofulaceum M. malmoense M. szulgai M. marinum M. tuberculosis M. gordonae M. simiae M. xenopi M. nonchromogenicum M. terrae Nocardia asteroides Mycobacteria have historically been categorized through phenotypic testing , such as

869-413: A phylogenetic tree of the genus' key species based on the earlier genetic sequencing of Rogall, et al. (1990), alongside new phylogentic trees based on Tortoli's 2017 sequencing of 148 Mycobacterium species: Gupta et al. have proposed dividing Mycobacterium into five genera, based on an analysis of 150 species in this genus. Due to controversy over complicating clinical diagnoses and treatment, all of

SECTION 10

#1733085517446

948-432: A receptor to inactivate mycobacteriophages . Replacement of the gene encoding mycocerosic acid synthase in M. bovis prevents formation of mycosides. Genus The composition of a genus is determined by taxonomists . The standards for genus classification are not strictly codified, so different authorities often produce different classifications for genera. There are some general practices used, however, including

1027-409: A reference for designating currently accepted genus names as opposed to others which may be either reduced to synonymy, or, in the case of prokaryotes, relegated to a status of "names without standing in prokaryotic nomenclature". An available (zoological) or validly published (botanical) name that has been historically applied to a genus but is not regarded as the accepted (current/valid) name for

1106-427: A taxon; however, the names published in suppressed works are made unavailable via the relevant Opinion dealing with the work in question. In botany, similar concepts exist but with different labels. The botanical equivalent of zoology's "available name" is a validly published name . An invalidly published name is a nomen invalidum or nom. inval. ; a rejected name is a nomen rejiciendum or nom. rej. ;

1185-455: A total of c. 520,000 published names (including synonyms) as at end 2019, increasing at some 2,500 published generic names per year. "Official" registers of taxon names at all ranks, including genera, exist for a few groups only such as viruses and prokaryotes, while for others there are compendia with no "official" standing such as Index Fungorum for fungi, Index Nominum Algarum and AlgaeBase for algae, Index Nominum Genericorum and

1264-442: A variety of environmental stressors. The agar media used for most water testing does not support the growth of mycobacteria, allowing it to go undetected in municipal and hospital systems. Hundreds of Mycobacterium genomes have been completely sequenced. The genome sizes of mycobacteria range from relatively small ones (e.g. in M. leprae ) to quite large ones, such as that as M. vulneris , encoding 6,653 proteins, larger than

1343-417: A waxy lipid-rich outer layer containing high concentrations of mycolic acid, acid-fast staining is used to emphasize their resistance to acids, compared to other cell types. Mycobacterial species are generally aerobic, non-motile, and capable of growing with minimal nutrition. The genus is divided based on each species' pigment production and growth rate. While most Mycobacterium species are non-pathogenic,

1422-470: A waxy outer mycomembrane of mycolic acid; and an outermost capsule of glucans and secreted proteins for virulence. It constantly remodels these layers to survive in stressful environments and avoid host immune defenses. This cell wall structure results in colony surfaces resembling fungi, leading to the genus' use of the Greek prefix myco- . This unique structure makes penicillins ineffective, instead requiring

1501-611: Is a lipid kinase that catalyzes the conversion of sphingosine to sphingosine-1-phosphate (S1P). Sphingolipids are ubiquitous membrane lipids. Upon activation, sphingosine kinase migrates from the cytosol to the plasma membrane where it transfers a γ phosphate (which is the last or terminal phosphate) from ATP or GTP to sphingosine. The S1P receptor is a GPCR receptor, so S1P has the ability to regulate G protein signaling. The resulting signal can activate intracellular effectors like ERKs, Rho GTPase , Rac GTPase , PLC , and AKT/PI3K. It can also exert its effect on target molecules inside

1580-506: Is a precursor to flavin adenine dinucleotide (FAD), a redox cofactor used by many enzymes, including many in metabolism . In fact, there are some enzymes that are capable of carrying out both the phosphorylation of riboflavin to FMN , as well as the FMN to FAD reaction. Riboflavin kinase may help prevent stroke, and could possibly be used as a treatment in the future. It is also implicated in infection, when studied in mice. Thymidine kinase

1659-1165: Is a thick, hydrophobic , and mycolic acid -rich cell wall made of peptidoglycan and arabinogalactan , with these unique components offering targets for new tuberculosis drugs. Many Mycobacterium species readily grow with minimal nutrients, using ammonia and/or amino acids as nitrogen sources and glycerol as a carbon source in the presence of mineral salts. Temperatures for optimal growth vary between species and media conditions, ranging from 25 to 45 °C. Most Mycobacterium species, including most clinically relevant species, can be cultured in blood agar . However, some species grow very slowly due to extremely long reproductive cycles, such as M. leprae requiring 12 days per division cycle compared to 20 minutes for some E. coli strains. Whereas Mycobacterium tuberculosis and M. leprae are pathogenic, most mycobacteria do not cause disease unless they enter skin lesions of those with pulmonary and/or immune dysfunction, despite being widespread across aquatic and terrestrial environments. Through biofilm formation, cell wall resistance to chlorine , and association with amoebas , mycobacteria can survive

SECTION 20

#1733085517446

1738-452: Is a tyrosine/threonine kinase. MAPK can regulate transcription factors directly or indirectly. Its major transcriptional targets include ATF-2, Chop, c-Jun, c-Myc, DPC4, Elk-1, Ets1, Max, MEF2C, NFAT4, Sap1a, STATs, Tal, p53, CREB, and Myc. MAPK can also regulate translation by phosphorylating the S6 kinase in the large ribosomal subunit. It can also phosphorylate components in the upstream portion of

1817-596: Is discouraged by both the International Code of Zoological Nomenclature and the International Code of Nomenclature for algae, fungi, and plants , there are some five thousand such names in use in more than one kingdom. For instance, A list of generic homonyms (with their authorities), including both available (validly published) and selected unavailable names, has been compiled by the Interim Register of Marine and Nonmarine Genera (IRMNG). The type genus forms

1896-560: Is enormous given that there are many ways to covalently modify a protein in addition to regulation provided by allosteric control. In his Hopkins Memorial Lecture, Edwin Krebs asserted that allosteric control evolved to respond to signals arising from inside the cell, whereas phosphorylation evolved to respond to signals outside of the cell. This idea is consistent with the fact that phosphorylation of proteins occurs much more frequently in eukaryotic cells in comparison to prokaryotic cells because

1975-535: Is known as phosphorylation , where the high-energy ATP molecule donates a phosphate group to the substrate molecule. As a result, kinase produces a phosphorylated substrate and ADP . Conversely, it is referred to as dephosphorylation when the phosphorylated substrate donates a phosphate group and ADP gains a phosphate group (producing a dephosphorylated substrate and the high energy molecule of ATP). These two processes, phosphorylation and dephosphorylation, occur four times during glycolysis . Kinases are part of

2054-412: Is one of the many nucleoside kinases that are responsible for nucleoside phosphorylation. It phosphorylates thymidine to create thymidine monophosphate (dTMP). This kinase uses an ATP molecule to supply the phosphate to thymidine, as shown below. This transfer of a phosphate from one nucleotide to another by thymidine kinase, as well as other nucleoside and nucleotide kinases, functions to help control

2133-551: Is present at higher concentrations in certain types of cancers. There are two kinases present in mammalian cells, SK1 and SK2. SK1 is more specific compared to SK2, and their expression patterns differ as well. SK1 is expressed in lung, spleen, and leukocyte cells, whereas SK2 is expressed in kidney and liver cells. The involvement of these two kinases in cell survival, proliferation, differentiation, and inflammation makes them viable candidates for chemotherapeutic therapies . [REDACTED] For many mammals, carbohydrates provide

2212-460: Is somewhat arbitrary. Although all species within a genus are supposed to be "similar", there are no objective criteria for grouping species into genera. There is much debate among zoologists about whether enormous, species-rich genera should be maintained, as it is extremely difficult to come up with identification keys or even character sets that distinguish all species. Hence, many taxonomists argue in favor of breaking down large genera. For instance,

2291-474: Is the type species , and the generic name is permanently associated with the type specimen of its type species. Should the specimen turn out to be assignable to another genus, the generic name linked to it becomes a junior synonym and the remaining taxa in the former genus need to be reassessed. In zoological usage, taxonomic names, including those of genera, are classified as "available" or "unavailable". Available names are those published in accordance with

2370-521: Is the most virulent rapidly-growing mycobacterium (RGM), as well as the leading cause of RGM based pulmonary infections. Although it has been traditionally viewed as an opportunistic pathogen like other NTMs, analysis of various virulence factors (VFs) have shifted this view to that of a true pathogen. This is due to the presence of known mycobacterial VFs and other non-mycobacterial VFs found in other prokaryotic pathogens. Mycobacteria have cell walls with peptidoglycan , arabinogalactan , and mycolic acid ;

2449-444: Is unstable and has a high energy. 1,3-bisphosphogylcerate kinase requires ADP to carry out its reaction yielding 3-phosphoglycerate and ATP. In the final step of glycolysis, pyruvate kinase transfers a phosphoryl group from phosphoenolpyruvate to ADP, generating ATP and pyruvate. Hexokinase is the most common enzyme that makes use of glucose when it first enters the cell. It converts D-glucose to glucose-6-phosphate by transferring

Mycobacterium - Misplaced Pages Continue

2528-467: The M, tuberculosis complex until they were finally merged into the main species in 2018. The development of Leprosy is caused by infection with either Mycobacterium leprae or Mycobacterium lepromatosis , two closely related bacteria. Roughly 200,000 new cases of infection are reported each year, and 80% of new cases are reported in Brazil, India, and Indonesia. M. leprae infection localizes within

2607-621: The International Code of Zoological Nomenclature ; the earliest such name for any taxon (for example, a genus) should then be selected as the " valid " (i.e., current or accepted) name for the taxon in question. Consequently, there will be more available names than valid names at any point in time; which names are currently in use depending on the judgement of taxonomists in either combining taxa described under multiple names, or splitting taxa which may bring available names previously treated as synonyms back into use. "Unavailable" names in zoology comprise names that either were not published according to

2686-799: The International Plant Names Index for plants in general, and ferns through angiosperms, respectively, and Nomenclator Zoologicus and the Index to Organism Names for zoological names. Totals for both "all names" and estimates for "accepted names" as held in the Interim Register of Marine and Nonmarine Genera (IRMNG) are broken down further in the publication by Rees et al., 2020 cited above. The accepted names estimates are as follows, broken down by kingdom: The cited ranges of uncertainty arise because IRMNG lists "uncertain" names (not researched therein) in addition to known "accepted" names;

2765-473: The Runyon classification of analyzing growth rate and production of yellow/orange carotenoid pigments. Group I contains photochromogens (pigment production induced by light), Group II comprises scotochromogens (constitutive pigment production), and the non-chromogens of Groups III and IV have a pale yellow/tan pigment, regardless of light exposure. Group IV species are "rapidly-growing" mycobacteria compared to

2844-404: The platypus belongs to the genus Ornithorhynchus although George Shaw named it Platypus in 1799 (these two names are thus synonyms ) . However, the name Platypus had already been given to a group of ambrosia beetles by Johann Friedrich Wilhelm Herbst in 1793. A name that means two different things is a homonym . Since beetles and platypuses are both members of the kingdom Animalia,

2923-862: The transition state by interacting with the negatively charged phosphate groups. Alternatively, some kinases utilize bound metal cofactors in their active sites to coordinate the phosphate groups. Protein kinases can be classed as catalytically active (canonical) or as pseudokinases , reflecting the evolutionary loss of one or more of the catalytic amino acids that position or hydrolyse ATP. However, in terms of signalling outputs and disease relevance, both kinases and pseudokinases are important signalling modulators in human cells, making kinases important drug targets. Kinases are used extensively to transmit signals and regulate complex processes in cells. Phosphorylation of molecules can enhance or inhibit their activity and modulate their ability to interact with other molecules. The addition and removal of phosphoryl groups provides

3002-1614: The "decade of protein kinase cascades". During this time, the MAPK/ERK pathway , the JAK kinases (a family of protein tyrosine kinases), and the PIP3-dependent kinase cascade were discovered. Kinases are classified into broad groups by the substrate they act upon: protein kinases, lipid kinases, carbohydrate kinases. Kinases can be found in a variety of species, from bacteria to mold to worms to mammals. More than five hundred different kinases have been identified in humans. Their diversity and their role in signaling makes them an interesting object of study. Various other kinases act on small molecules such as lipids , carbohydrates , amino acids , and nucleotides , either for signaling or to prime them for metabolic pathways. Specific kinases are often named after their substrates. Protein kinases often have multiple substrates, and proteins can serve as substrates for more than one specific kinase. For this reason protein kinases are named based on what regulates their activity (i.e. Calmodulin-dependent protein kinases). Sometimes they are further subdivided into categories because there are several isoenzymatic forms. For example, type I and type II cyclic-AMP dependent protein kinases have identical catalytic subunits but different regulatory subunits that bind cyclic AMP. Protein kinases act on proteins, by phosphorylating them on their serine, threonine, tyrosine, or histidine residues. Phosphorylation can modify

3081-641: The "slowly-growing" Group III species because samples grow into visible colonies in less than seven days. Because the International Code of Nomenclature of Prokaryotes (ICNP) currently recognizes 195 Mycobacterium species, classification and identification systems now rely on DNA sequencing and computational phylogenetics . The major disease-causing groups are the M. tuberculosis complex ( tuberculosis ), M. avium complex ( mycobacterium avium-intracellulare infection ), M. leprae and M. lepromatosis ( leprosy ), and M. abscessus ( chronic lung infection ). Microbiologist Enrico Tortoli has constructed

3160-469: The French botanist Joseph Pitton de Tournefort (1656–1708) is considered "the founder of the modern concept of genera". The scientific name (or the scientific epithet) of a genus is also called the generic name ; in modern style guides and science, it is always capitalised. It plays a fundamental role in binomial nomenclature , the system of naming organisms , where it is combined with the scientific name of

3239-537: The MAPK signalling cascade including Ras, Sos, and the EGF receptor itself. The carcinogenic potential of the MAPK pathway makes it clinically significant. It is implicated in cell processes that can lead to uncontrolled growth and subsequent tumor formation. Mutations within this pathway alter its regulatory effects on cell differentiation , proliferation, survival, and apoptosis , all of which are implicated in various forms of cancer . Lipid kinases phosphorylate lipids in

Mycobacterium - Misplaced Pages Continue

3318-546: The PFK gene that reduces its activity. Kinases act upon many other molecules besides proteins, lipids, and carbohydrates. There are many that act on nucleotides (DNA and RNA) including those involved in nucleotide interconverstion, such as nucleoside-phosphate kinases and nucleoside-diphosphate kinases . Other small molecules that are substrates of kinases include creatine , phosphoglycerate , riboflavin , dihydroxyacetone , shikimate , and many others. Riboflavin kinase catalyzes

3397-442: The base for higher taxonomic ranks, such as the family name Canidae ("Canids") based on Canis . However, this does not typically ascend more than one or two levels: the order to which dogs and wolves belong is Carnivora ("Carnivores"). The numbers of either accepted, or all published genus names is not known precisely; Rees et al., 2020 estimate that approximately 310,000 accepted names (valid taxa) may exist, out of

3476-604: The cell cycle. Additionally, the phosphorylation state of CDKs is also critical to their activity, as they are subject to regulation by other kinases (such as CDK-activating kinase ) and phosphatases (such as Cdc25 ). Once the CDKs are active, they phosphorylate other proteins to change their activity, which leads to events necessary for the next stage of the cell cycle. While they are most known for their function in cell cycle control, CDKs also have roles in transcription, metabolism, and other cellular events. Because of their key role in

3555-432: The cell with a means of control because various kinases can respond to different conditions or signals. Mutations in kinases that lead to a loss-of-function or gain-of-function can cause cancer and disease in humans, including certain types of leukemia and neuroblastomas , glioblastoma , spinocerebellar ataxia (type 14), forms of agammaglobulinaemia , and many others. The first protein to be recognized as catalyzing

3634-686: The cell, both on the plasma membrane as well as on the membranes of the organelles. The addition of phosphate groups can change the reactivity and localization of the lipid and can be used in signal transmission. Phosphatidylinositol kinases phosphorylate phosphatidylinositol species, to create species such as phosphatidylinositol 3,4-bisphosphate (PI(3,4)P 2 ), phosphatidylinositol 3,4,5-trisphosphate (PIP 3 ), and phosphatidylinositol 3-phosphate (PI3P). The kinases include phosphoinositide 3-kinase (PI3K), phosphatidylinositol-4-phosphate 3-kinase , and phosphatidylinositol-4,5-bisphosphate 3-kinase . The phosphorylation state of phosphatidylinositol plays

3713-412: The cell. A common point of confusion arises when thinking about the different ways a cell achieves biological regulation. There are countless examples of covalent modifications that cellular proteins can undergo; however, phosphorylation is one of the few reversible covalent modifications. This provided the rationale that phosphorylation of proteins is regulatory. The potential to regulate protein function

3792-414: The cell. S1P has been shown to directly inhibit the histone deacetylase activity of HDACs . In contrast, the dephosphorylated sphingosine promotes cell apoptosis , and it is therefore critical to understand the regulation of SKs because of its role in determining cell fate. Past research shows that SKs may sustain cancer cell growth because they promote cellular-proliferation, and SK1 (a specific type of SK)

3871-435: The controlling cell division, mutations in CDKs are often found in cancerous cells. These mutations lead to uncontrolled growth of the cells, where they are rapidly going through the whole cell cycle repeatedly. CDK mutations can be found in lymphomas , breast cancer , pancreatic tumors , and lung cancer . Therefore, inhibitors of CDK have been developed as treatments for some types of cancer. MAP kinases (MAPKs) are

3950-407: The conversion of fructose-6-phosphate to fructose-1,6-bisphosphate and is an important point in the regulation of glycolysis. High levels of ATP, H , and citrate inhibit PFK. If citrate levels are high, it means that glycolysis is functioning at an optimal rate. High levels of AMP stimulate PFK. Tarui's disease , a glycogen storage disease that leads to exercise intolerance, is due to a mutation in

4029-405: The first month. Growth media include Löwenstein–Jensen medium and mycobacteria growth indicator tube (MGIT). Mycobacteria can be infected by mycobacteriophages , a class of viruses with high specificity for their targets. By hijacking the cellular machinery of mycobacteria to produce additional phages, such viruses can be used in phage therapy for eukaryotic hosts, as they would die alongside

SECTION 50

#1733085517446

4108-446: The form "author, year" in zoology, and "standard abbreviated author name" in botany. Thus in the examples above, the genus Canis would be cited in full as " Canis Linnaeus, 1758" (zoological usage), while Hibiscus , also first established by Linnaeus but in 1753, is simply " Hibiscus L." (botanical usage). Each genus should have a designated type , although in practice there is a backlog of older names without one. In zoology, this

4187-460: The function of a protein in many ways. It can increase or decrease a protein's activity, stabilize it or mark it for destruction, localize it within a specific cellular compartment, and it can initiate or disrupt its interaction with other proteins. The protein kinases make up the majority of all kinases and are widely studied. These kinases, in conjunction with phosphatases , play a major role in protein and enzyme regulation as well as signalling in

4266-467: The gamma phosphate of an ATP to the C6 position. This is an important step in glycolysis because it traps glucose inside the cell due to the negative charge. In its dephosphorylated form, glucose can move back and forth across the membrane very easily. Mutations in the hexokinase gene can lead to a hexokinase deficiency which can cause nonspherocytic hemolytic anemia . Phosphofructokinase , or PFK, catalyzes

4345-727: The generic name (or its abbreviated form) still forms the leading portion of the scientific name, for example, Canis lupus lupus for the Eurasian wolf subspecies, or as a botanical example, Hibiscus arnottianus ssp. immaculatus . Also, as visible in the above examples, the Latinised portions of the scientific names of genera and their included species (and infraspecies, where applicable) are, by convention, written in italics . The scientific names of virus species are descriptive, not binomial in form, and may or may not incorporate an indication of their containing genus; for example,

4424-572: The genus' characteristic complex cell wall contributes to evasion from host defenses. Mycobacteria are aerobic with 0.2-0.6 μm wide and 1.0-10 μm long rod shapes . They are generally non-motile , except for the species Mycobacterium marinum , which has been shown to be motile within macrophages . Mycobacteria possess capsules and most do not form endospores . M. marinum and perhaps M. bovis have been shown to sporulate ; however, this has been contested by further research. The distinguishing characteristic of all Mycobacterium species

4503-432: The idea that a newly defined genus should fulfill these three criteria to be descriptively useful: Moreover, genera should be composed of phylogenetic units of the same kind as other (analogous) genera. The term "genus" comes from Latin genus , a noun form cognate with gignere ('to bear; to give birth to'). The Swedish taxonomist Carl Linnaeus popularized its use in his 1753 Species Plantarum , but

4582-652: The larger family of phosphotransferases . Kinases should not be confused with phosphorylases , which catalyze the addition of inorganic phosphate groups to an acceptor, nor with phosphatases , which remove phosphate groups (dephosphorylation). The phosphorylation state of a molecule, whether it be a protein , lipid or carbohydrate , can affect its activity, reactivity and its ability to bind other molecules. Therefore, kinases are critical in metabolism , cell signalling , protein regulation , cellular transport , secretory processes and many other cellular pathways, which makes them very important to physiology. Kinases mediate

4661-628: The largest component, with 23,236 ± 5,379 accepted genus names, of which 20,845 ± 4,494 are angiosperms (superclass Angiospermae). By comparison, the 2018 annual edition of the Catalogue of Life (estimated >90% complete, for extant species in the main) contains currently 175,363 "accepted" genus names for 1,744,204 living and 59,284 extinct species, also including genus names only (no species) for some groups. The number of species in genera varies considerably among taxonomic groups. For instance, among (non-avian) reptiles , which have about 1180 genera,

4740-448: The level of each of the different nucleotides. After creation of the dTMP molecule, another kinase, thymidylate kinase , can act upon dTMP to create the diphosphate form, dTDP. Nucleoside diphosphate kinase catalyzes production of thymidine triphosphate , dTTP, which is used in DNA synthesis . Because of this, thymidine kinase activity is closely correlated with the cell cycle and used as

4819-434: The lizard genus Anolis has been suggested to be broken down into 8 or so different genera which would bring its ~400 species to smaller, more manageable subsets. Kinase In biochemistry , a kinase ( / ˈ k aɪ n eɪ s , ˈ k ɪ n eɪ s , - eɪ z / ) is an enzyme that catalyzes the transfer of phosphate groups from high-energy , phosphate-donating molecules to specific substrates . This process

SECTION 60

#1733085517446

4898-416: The more complex cell type evolved to respond to a wider array of signals. Cyclin dependent kinases (CDKs) are a group of several different kinases involved in regulation of the cell cycle . They phosphorylate other proteins on their serine or threonine residues, but CDKs must first bind to a cyclin protein in order to be active. Different combinations of specific CDKs and cyclins mark different parts of

4977-403: The most (>300) have only 1 species, ~360 have between 2 and 4 species, 260 have 5–10 species, ~200 have 11–50 species, and only 27 genera have more than 50 species. However, some insect genera such as the bee genera Lasioglossum and Andrena have over 1000 species each. The largest flowering plant genus, Astragalus , contains over 3,000 species. Which species are assigned to a genus

5056-487: The mycobacteria. Since only some mycobacteriophages are capable of penetrating the M. tuberculosis membrane, the viral DNA may be delivered through artificial liposomes because bacteria uptake, transcribe, and translate foreign DNA into proteins. Mycosides are glycolipids isolated from Mycobacterium species with Mycoside A found in photochromogenic strains, Mycoside B in bovine strains, and Mycoside C in avian strains. Different forms of Mycoside C have varying success as

5135-428: The name could not be used for both. Johann Friedrich Blumenbach published the replacement name Ornithorhynchus in 1800. However, a genus in one kingdom is allowed to bear a scientific name that is in use as a generic name (or the name of a taxon in another rank) in a kingdom that is governed by a different nomenclature code. Names with the same form but applying to different taxa are called "homonyms". Although this

5214-399: The phosphorylation of riboflavin to create flavin mononucleotide (FMN). It has an ordered binding mechanism where riboflavin must bind to the kinase before it binds to the ATP molecule. Divalent cations help coordinate the nucleotide . The general mechanism is shown in the figure below. Riboflavin kinase plays an important role in cells, as FMN is an important cofactor . FMN also

5293-468: The phosphorylation of another protein using ATP was observed in 1954 by Eugene P. Kennedy at which time he described a liver enzyme that catalyzed the phosphorylation of casein. In 1956, Edmond H. Fischer and Edwin G. Krebs discovered that the interconversion between phosphorylase a and phosphorylase b was mediated by phosphorylation and dephosphorylation. The kinase that transferred a phosphoryl group to Phosphorylase b, converting it to Phosphorylase a,

5372-526: The provisions of the ICZN Code, e.g., incorrect original or subsequent spellings, names published only in a thesis, and generic names published after 1930 with no type species indicated. According to "Glossary" section of the zoological Code, suppressed names (per published "Opinions" of the International Commission of Zoological Nomenclature) remain available but cannot be used as the valid name for

5451-606: The renamed species have retained their original identity in the Mycobacterium genus as a valid taxonomic synonym: The two most common methods for visualizing these acid-fast bacilli as bright red against a blue background are the Ziehl-Neelsen stain and modified Kinyoun stain . Fite's stain is used to color M. leprae cells as pink against a blue background. Rapid Modified Auramine O Fluorescent staining has specific binding to slowly-growing mycobacteria for yellow staining against

5530-681: The skin macrophages and Schwann cells found in peripheral nerve tissue. Nontuberculosis Mycobacteria (NTM), which exclude M. tuberculosis , M. leprae , and M. lepromatosis, can infect mammalian hosts. These bacteria are referred to as "atypical mycobacteria." Although person-to-person transmission is rare, transmission of M. abscessus has been observed between patients with cystic fibrosis . The four primary diseases observed in humans are chronic pulmonary disease, disseminated disease in immunocompromised patients, skin and soft tissue infections, and superficial lymphadenitis. 80-90% of recorded NTM infections manifest as pulmonary diseases. M. abscessus

5609-497: The specific name particular to the wolf. A botanical example would be Hibiscus arnottianus , a particular species of the genus Hibiscus native to Hawaii. The specific name is written in lower-case and may be followed by subspecies names in zoology or a variety of infraspecific names in botany . When the generic name is already known from context, it may be shortened to its initial letter, for example, C. lupus in place of Canis lupus . Where species are further subdivided,

5688-412: The standard format for a species name comprises the generic name, indicating the genus to which the species belongs, followed by the specific epithet, which (within that genus) is unique to the species. For example, the gray wolf 's scientific name is Canis lupus , with Canis ( Latin for 'dog') being the generic name shared by the wolf's close relatives and lupus (Latin for 'wolf') being

5767-403: The taxon is termed a synonym ; some authors also include unavailable names in lists of synonyms as well as available names, such as misspellings, names previously published without fulfilling all of the requirements of the relevant nomenclatural code, and rejected or suppressed names. A particular genus name may have zero to many synonyms, the latter case generally if the genus has been known for

5846-493: The transfer of a phosphate moiety from a high energy molecule (such as ATP ) to their substrate molecule, as seen in the figure below. Kinases are needed to stabilize this reaction because the phosphoanhydride bond contains a high level of energy. Kinases properly orient their substrate and the phosphoryl group within their active sites, which increases the rate of the reaction. Additionally, they commonly use positively charged amino acid residues, which electrostatically stabilize

5925-566: The values quoted are the mean of "accepted" names alone (all "uncertain" names treated as unaccepted) and "accepted + uncertain" names (all "uncertain" names treated as accepted), with the associated range of uncertainty indicating these two extremes. Within Animalia, the largest phylum is Arthropoda , with 151,697 ± 33,160 accepted genus names, of which 114,387 ± 27,654 are insects (class Insecta). Within Plantae, Tracheophyta (vascular plants) make up

6004-429: The virus species " Salmonid herpesvirus 1 ", " Salmonid herpesvirus 2 " and " Salmonid herpesvirus 3 " are all within the genus Salmonivirus ; however, the genus to which the species with the formal names " Everglades virus " and " Ross River virus " are assigned is Alphavirus . As with scientific names at other ranks, in all groups other than viruses, names of genera may be cited with their authorities, typically in

6083-626: The ~6000 proteins of eukaryotic yeast . Mycobacterium tuberculosis can remain latent in human hosts for decades after an initial infection, allowing it to continue infecting others. It has been estimated that a third of the world population has latent tuberculosis (TB). M. tuberculosis has many virulence factors , which can be divided across lipid and fatty acid metabolism, cell envelope proteins, macrophage inhibitors, kinase proteins, proteases , metal-transporter proteins, and gene expression regulators. Several lineages such as M. t. var. bovis (bovine TB) were considered separate species in

6162-486: Was named Phosphorylase Kinase. Years later, the first example of a kinase cascade was identified, whereby Protein Kinase A (PKA) phosphorylates Phosphorylase Kinase. At the same time, it was found that PKA inhibits glycogen synthase , which was the first example of a phosphorylation event that resulted in inhibition. In 1969, Lester Reed discovered that pyruvate dehydrogenase was inactivated by phosphorylation, and this discovery

6241-475: Was the first clue that phosphorylation might serve as a means of regulation in other metabolic pathways besides glycogen metabolism. In the same year, Tom Langan discovered that PKA phosphorylates histone H1, which suggested phosphorylation might regulate nonenzymatic proteins. The 1970s included the discovery of calmodulin-dependent protein kinases and the finding that proteins can be phosphorylated on more than one amino acid residue. The 1990s may be described as

#445554