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77-433: See text. Corynebacterium ( / k ɔː ˈ r aɪ n ə b æ k ˌ t ɪər i ə m , - ˈ r ɪ n -/ ) is a genus of Gram-positive bacteria and most are aerobic . They are bacilli (rod-shaped), and in some phases of life they are, more specifically, club -shaped, which inspired the genus name ( coryneform means "club-shaped"). They are widely distributed in nature in the microbiota of animals (including

154-465: A buildup of intermediates occurs, so scientists have developed mutant strains of C. glutamicum through PCR engineering and chemical knockouts to ensure production of side-reaction enzymes are limited. Many genetic manipulations conducted in industry are by traditional cross-over methods or inhibition of transcriptional activators. Expression of functionally active human epidermal growth factor has been brought about in C. glutamicum , thus demonstrating

231-802: A characteristic way, which has been described as the form of a "V", "palisades", or "Chinese characters". They may also appear elliptical . They are aerobic or facultatively anaerobic , chemoorganotrophs . They are pleomorphic through their lifecycles , they occur in various lengths, and they frequently have thickenings at either end, depending on the surrounding conditions. Some corynebacteria are lipophilic (such as CDC coryneform groups F-1 and G, C. accolens , C. afermentans subsp. lipophilum , C. bovis , C. jeikeium , C. macginleyi , C. uropygiale , and C. urealyticum ), but medically relevant corynebacteria are typically not. The nonlipophilic bacteria may be classified as fermentative (such as C. amycolatum ; C. argentoratense , members of

308-682: A complex commonly seen in Corynebacterium species: the mycolyl-AG–peptidoglican (mAGP). Unlike most corynebacteria, Corynebacterium kroppenstedtii does not contain mycolic acids. Corynebacteria grow slowly, even on enriched media. In nutritional requirements, all need biotin to grow. Some strains also need thiamine and PABA . Some of the Corynebacterium species with sequenced genomes have between 2.5 and 3.0 million base pairs. The bacteria grow in Loeffler's medium , blood agar , and trypticase soy agar (TSA). They form small, grayish colonies with

385-476: A conserved region of the enzyme phosphoribose diphosphate:decaprenyl-phosphate phosphoribosyltransferase and a three-amino-acid insertion in acetate kinase , both of which are found only in Corynebacterium species. Both of these indels serve as molecular markers for species of the genus Corynebacterium . Additionally, 16 conserved signature proteins, which are uniquely found in Corynebacterium species, have been identified. Three of these have homologs found in

462-407: 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 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

539-578: A granular appearance, mostly translucent, but with opaque centers, convex, with continuous borders. The color tends to be yellowish-white in Loeffler's medium. In TSA, they can form grey colonies with black centers and dentated borders that either resemble flowers ( C. gravis ), continuous borders ( C. mitis ), or a mix between the two forms ( C. intermedium ). Corynebacterium species occur commonly in nature in soil, water, plants, and food products. The non-diphtheroid Corynebacterium species can even be found in

616-496: A high G+C content ranging from 46-74 mol%. The principal features of the genus Corynebacterium were described by Collins and Cummins, for Coryn Taylor in 1986. They are gram-positive, catalase -positive, non- spore -forming, non- motile , rod-shaped bacteria that are straight or slightly curved. Metachromatic granules are usually present representing stored phosphate regions. Their size falls between 2 and 6 μm in length and 0.5 μm in diameter. The bacteria group together in

693-643: 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

770-621: 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,

847-616: A pathogen is called a granuloma . Many bacteria are catalase positive, but some are better catalase-producers than others. Some catalase-positive bacteria and fungi include: Nocardia , Pseudomonas , Listeria , Aspergillus , Candida , E. coli , Staphylococcus , Serratia , B. cepacia and H. pylori . Acatalasia is a condition caused by homozygous mutations in CAT, resulting in a lack of catalase. Symptoms are mild and include oral ulcers. A heterozygous CAT mutation results in lower, but still present catalase. Low levels of catalase may play

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924-516: A pathogen. Catalase-positive pathogens, such as Mycobacterium tuberculosis , Legionella pneumophila , and Campylobacter jejuni , make catalase to deactivate the peroxide radicals, thus allowing them to survive unharmed within the host . Like alcohol dehydrogenase , catalase converts ethanol to acetaldehyde, but it is unlikely that this reaction is physiologically significant. The large majority of known organisms use catalase in every organ , with particularly high concentrations occurring in

1001-449: A potential for industrial-scale production of human proteins. Expressed proteins can be targeted for secretion through either the general secretory pathway or the twin-arginine translocation pathway . Unlike gram-negative bacteria, the gram-positive Corynebacterium species lack lipopolysaccharides that function as antigenic endotoxins in humans. Corynebacterium comprises the following species: Genus The composition of

1078-626: A reduction in catalase activity in tissues, such as heart and liver." Furthermore, the poison cyanide is a noncompetitive inhibitor of catalase at high concentrations of hydrogen peroxide . Arsenate acts as an activator . Three-dimensional protein structures of the peroxidated catalase intermediates are available at the Protein Data Bank . Hydrogen peroxide is a harmful byproduct of many normal metabolic processes; to prevent damage to cells and tissues, it must be quickly converted into other, less dangerous substances. To this end, catalase

1155-409: 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

1232-471: A role in the graying process of human hair. Hydrogen peroxide is naturally produced by the body and broken down by catalase. Hydrogen peroxide can accumulate in hair follicles and if catalase levels decline, this buildup can cause oxidative stress and graying. These low levels of catalase are associated with old age. Hydrogen peroxide interferes with the production of melanin , the pigment that gives hair its color. Catalase has been shown to interact with

1309-484: A small amount of bacterial isolate is added to hydrogen peroxide. The catalase test is done by placing a drop of hydrogen peroxide on a microscope slide . An applicator stick is touched to the colony, and the tip is then smeared onto the hydrogen peroxide drop. While the catalase test alone cannot identify a particular organism, it can aid identification when combined with other tests such as antibiotic resistance. The presence of catalase in bacterial cells depends on both

1386-427: 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. ;

1463-455: 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

1540-415: Is a tetramer of four polypeptide chains, each over 500 amino acids long. It contains four iron-containing heme groups that allow the enzyme to react with hydrogen peroxide. The optimum pH for human catalase is approximately 7, and has a fairly broad maximum: the rate of reaction does not change appreciably between pH 6.8 and 7.5. The pH optimum for other catalases varies between 4 and 11 depending on

1617-501: Is a common enzyme found in nearly all living organisms exposed to oxygen (such as bacteria , plants, and animals) which catalyzes the decomposition of hydrogen peroxide to water and oxygen . It is a very important enzyme in protecting the cell from oxidative damage by reactive oxygen species (ROS). Catalase has one of the highest turnover numbers of all enzymes; one catalase molecule can convert millions of hydrogen peroxide molecules to water and oxygen each second. Catalase

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1694-566: Is alleviated by over-expression of catalase. Over-expressing mice do not exhibit the age-associated loss of spermatozoa , testicular germ and Sertoli cells seen in wild-type mice. Oxidative stress in wild-type mice ordinarily induces oxidative DNA damage (measured as 8-oxodG ) in sperm with aging, but these damages are significantly reduced in aged catalase over-expressing mice. Furthermore, these over-expressing mice show no decrease in age-dependent number of pups per litter. Overexpression of catalase targeted to mitochondria extends

1771-596: 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

1848-546: Is distinguished by several conserved signature indels, such as a two-amino-acid insertion in LepA and a seven- or eight-amino-acid insertions in RpoC. Also, 21 conserved signature proteins are found only in members of cluster I. Another cluster has been proposed, consisting of C. jeikeium and C. urealyticum , which is supported by the presence of 19 distinct conserved signature proteins which are unique to these two species. Corynebacteria have

1925-516: Is frequently used by cells to rapidly catalyze the decomposition of hydrogen peroxide into less-reactive gaseous oxygen and water molecules. Mice genetically engineered to lack catalase are initially phenotypically normal. However, catalase deficiency in mice may increase the likelihood of developing obesity , fatty liver, and type 2 diabetes . Some humans have very low levels of catalase ( acatalasia ), yet show few ill effects. The increased oxidative stress that occurs with aging in mice

2002-449: Is more common in developing countries It can occasionally infect wounds, the vulva , the conjunctiva , and the middle ear . It can be spread within a hospital . The virulent and toxigenic strains produce an exotoxin formed by two polypeptide chains, which is itself produced when a bacterium is transformed by a gene from the β prophage . Several species cause disease in animals, most notably C. pseudotuberculosis , which causes

2079-468: Is peroxide-free. A minor use is in contact lens hygiene – a few lens-cleaning products disinfect the lens using a hydrogen peroxide solution; a solution containing catalase is then used to decompose the hydrogen peroxide before the lens is used again. The catalase test is one of the three main tests used by microbiologists to identify species of bacteria. If the bacteria possess catalase (i.e., are catalase-positive), bubbles of oxygen are observed when

2156-460: 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,

2233-547: Is specific to C. glutamicum in which core metabolic enzymes are manipulated through genetic engineering to drive metabolic flux towards the production of NADPH from the pentose phosphate pathway, and L-4-aspartyl phosphate, the commitment step to the synthesis of L-lysine, lysC , dapA, dapC, and dapF. These enzymes are up-regulated in industry through genetic engineering to ensure adequate amounts of lysine precursors are produced to increase metabolic flux. Unwanted side reactions such as threonine and asparagine production can occur if

2310-474: 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

2387-414: Is used to represent corynebacteria that are non pathogenic ; for example, C. diphtheriae would be excluded. The term diphtheroid comes from Greek διφθέρα, diphthérā 'prepared hide, leather'. Comparative analysis of corynebacterial genomes has led to the identification of several conserved signature indels (CSIs) that are unique to the genus. Two examples of CSIs are a two-amino-acid insertion in

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2464-434: Is very exothermic (ΔH = −202.8 kJ/mol) and rapidly heats the mixture to the boiling point. Long-lived queens of the termite Reticulitermes speratus have significantly lower oxidative damage to their DNA than non-reproductive individuals (workers and soldiers). Queens have more than two times higher catalase activity and seven times higher expression levels of the catalase gene RsCAT1 than workers. It appears that

2541-549: The ABL2 and Abl genes. Infection with the murine leukemia virus causes catalase activity to decline in the lungs, heart and kidneys of mice. Conversely, dietary fish oil increased catalase activity in the heart, and kidneys of mice. In 1870, Schoenn discovered a formation of yellow color from the interaction of hydrogen peroxide with molybdate; then, from the middle of the 20th century, this reaction began to be used for colorimetric determination of unreacted hydrogen peroxide in

2618-601: The C. diphtheriae group, C. glucuronolyticum , C. glutamicum , C. matruchotii , C. minutissimum , C. striatum , and C. xerosis ) or nonfermentative (such as C. afermentans subsp. afermentans , C. auris , C. pseudodiphtheriticum , and C. propinquum ). The cell wall is distinctive, with a predominance of mesodiaminopimelic acid in the murein wall and many repetitions of arabinogalactan , as well as corynemycolic acid (a mycolic acid with 22 to 26 carbon atoms), bound by disaccharide bonds called L-Rha p -(1 → 4)--D-GlcNAc-phosphate. These form

2695-621: 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

2772-799: 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;

2849-407: The amino acids Asn148 ( asparagine at position 148) and His75 , causing a proton (hydrogen ion ) to transfer between the oxygen atoms. The free oxygen atom coordinates, freeing the newly formed water molecule and Fe(IV)=O. Fe(IV)=O reacts with a second hydrogen peroxide molecule to reform Fe(III)-E and produce water and oxygen. The reactivity of the iron center may be improved by the presence of

2926-612: The human microbiota ) and are mostly innocuous, most commonly existing in commensal relationships with their hosts. Some, such as C. glutamicum , are commercially and industrially useful. Others can cause human disease, including, most notably, diphtheria , which is caused by C. diphtheriae . Like various species of microbiota (including their relatives in the genera Arcanobacterium and Trueperella ), they usually are not pathogenic , but can occasionally opportunistically capitalize on atypical access to tissues (via wounds ) or weakened host defenses . The genus Corynebacterium

3003-410: The hyperthermophile archaeon Pyrobaculum calidifontis has a temperature optimum of 90 °C. Catalase is used in the food industry for removing hydrogen peroxide from milk prior to cheese production. Another use is in food wrappers, where it prevents food from oxidizing . Catalase is also used in the textile industry, removing hydrogen peroxide from fabrics to make sure the material

3080-520: The liver in mammals. Catalase is found primarily in peroxisomes and the cytosol of erythrocytes (and sometimes in mitochondria ) Almost all aerobic microorganisms use catalase. It is also present in some anaerobic microorganisms , such as Methanosarcina barkeri . Catalase is also universal among plants and occurs in most fungi . One unique use of catalase occurs in the bombardier beetle . This beetle has two sets of liquids that are stored separately in two paired glands. The larger of

3157-742: The mucosa and normal skin flora of humans and animals. Unusual habitats, such as the preen gland of birds , have been recently reported for Corynebacterium uropygiale . Some species are known for their pathogenic effects in humans and other animals. Perhaps the most notable one is C. diphtheriae , which acquires the capacity to produce diphtheria toxin only after interacting with a bacteriophage . Other pathogenic species in humans include: C. amycolatum , C. striatum , C. jeikeium , C. urealyticum , and C. xerosis ; all of these are important as pathogens in immunosuppressed patients. Pathogenic species in other animals include C. bovis and C. renale . This genus has been found to be part of

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3234-419: 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 ,

3311-438: The phagosome , which is converted via hydrogen peroxide to other oxidising substances like hypochlorous acid which kill phagocytosed pathogens. In individuals with chronic granulomatous disease (CGD), phagocytic peroxide production is impaired due to a defective NADPH oxidase system. Normal cellular metabolism will still produce a small amount of peroxide and this peroxide can be used to produce hypochlorous acid to eradicate

3388-404: 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,

3465-423: The reaction is believed to occur in two stages: Here Fe()-E represents the iron center of the heme group attached to the enzyme. Fe(IV)-E(.+) is a mesomeric form of Fe(V)-E, meaning the iron is not completely oxidized to +V, but receives some stabilising electron density from the heme ligand, which is then shown as a radical cation (.+). As hydrogen peroxide enters the active site , it does not interact with

3542-434: The bacterial infection. However, if individuals with CGD are infected with catalase-positive bacteria, the bacterial catalase can destroy the excess peroxide before it can be used to produce other oxidising substances. In these individuals the pathogen survives and becomes a chronic infection. This chronic infection is typically surrounded by macrophages in an attempt to isolate the infection. This wall of macrophages surrounding

3619-442: 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

3696-440: The catalase activity assay. The reaction became widely used after publications by Korolyuk et al. (1988) and Goth (1991). The first paper describes serum catalase assay with no buffer in the reaction medium; the latter describes the procedure based on phosphate buffer as a reaction medium. Since phosphate ion reacts with ammonium molybdate, the use of MOPS buffer as a reaction medium is more appropriate. Direct UV measurement of

3773-637: The disease caseous lymphadenitis , and some are also pathogenic in humans. Some attack healthy hosts , while others tend to attack the immunocompromised . Effects of infection include granulomatous lymphadenopathy , pneumonitis , pharyngitis , skin infections, and endocarditis . Corynebacterial endocarditis is seen most frequently in patients with intravascular devices. Several species of Corynebacterium can cause trichomycosis axillaris . C. striatum may cause axillary odor. C. minutissimum causes erythrasma . Nonpathogenic species of Corynebacterium are used for important industrial applications, such as

3850-485: The efficient antioxidant capability of termite queens can partly explain how they attain longer life. Catalase enzymes from various species have vastly differing optimum temperatures. Poikilothermic animals typically have catalases with optimum temperatures in the range of 15-25 °C, while mammalian or avian catalases might have optimum temperatures above 35 °C, and catalases from plants vary depending on their growth habit . In contrast, catalase isolated from

3927-446: 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

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4004-727: 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,

4081-425: The genus Dietzia , which is believed to be the closest related genus to Corynebacterium . In phylogenetic trees based on concatenated protein sequences or 16S rRNA, the genus Corynebacterium forms a distinct clade, within which is a distinct subclade, cluster I. The cluster is made up of the species C. diphtheriae, C. pseudotuberculosis, C. ulcerans, C. aurimucosum, C. glutamicum, and C. efficiens . This cluster

4158-434: The growth condition and the medium used to grow the cells. Capillary tubes may also be used. A small sample of bacteria is collected on the end of the capillary tube, without blocking the tube, to avoid false negative results. The opposite end is then dipped into hydrogen peroxide, which is drawn into the tube through capillary action , and turned upside down, so that the bacterial sample points downwards. The hand holding

4235-612: The human salivary microbiome . The most notable human infection is diphtheria , caused by C. diphtheriae . It is an acute, contagious infection characterized by pseudomembranes of dead epithelial cells , white blood cells , red blood cells , and fibrin that form around the tonsils and back of the throat . In developed countries, it is an uncommon illness that tends to occur in un vaccinated individuals, especially school-aged children, elderly , neutropenic or immunocompromised patients, and those with prosthetic devices such as prosthetic heart valves , shunts , or catheters . It

4312-628: 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,

4389-440: The lifespan of mice. In eukaryotes , catalase is usually located in a cellular organelle called the peroxisome . Peroxisomes in plant cells are involved in photorespiration (the use of oxygen and production of carbon dioxide) and symbiotic nitrogen fixation (the breaking apart of diatomic nitrogen (N 2 ) to reactive nitrogen atoms). Hydrogen peroxide is used as a potent antimicrobial agent when cells are infected with

4466-399: 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. Catalase 1DGB , 1DGF , 1DGG , 1DGH , 1F4J , 1QQW 847 12359 ENSG00000121691 ENSMUSG00000027187 P04040 P24270 NM_001752 NM_009804 NP_001743 NP_033934 Catalase

4543-403: 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

4620-428: 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

4697-422: The oxidation, by hydrogen peroxide , of various metabolites and toxins, including formaldehyde , formic acid , phenols , acetaldehyde and alcohols . It does so according to the following reaction: The exact mechanism of this reaction is not known. Any heavy metal ion (such as copper cations in copper(II) sulfate ) can act as a noncompetitive inhibitor of catalase. However, "Copper deficiency can lead to

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4774-406: The pair, the storage chamber or reservoir, contains hydroquinones and hydrogen peroxide, while the smaller, the reaction chamber, contains catalases and peroxidases . To activate the noxious spray, the beetle mixes the contents of the two compartments, causing oxygen to be liberated from hydrogen peroxide. The oxygen oxidizes the hydroquinones and also acts as the propellant. The oxidation reaction

4851-498: The phenolate ligand of Tyr358 in the fifth coordination position, which can assist in the oxidation of the Fe(III) to Fe(IV). The efficiency of the reaction may also be improved by the interactions of His75 and Asn148 with reaction intermediates . The decomposition of hydrogen peroxide by catalase proceeds according to first-order kinetics, the rate being proportional to the hydrogen peroxide concentration. Catalase can also catalyze

4928-443: The production of amino acids and nucleotides , bioconversion of steroids , degradation of hydrocarbons , cheese aging, and production of enzymes . Some species produce metabolites similar to antibiotics : bacteriocins of the corynecin-linocin type, antitumor agents, etc. One of the most studied species is C. glutamicum , whose name refers to its capacity to produce glutamic acid in aerobic conditions. L-Lysine production

5005-526: 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

5082-466: 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 the French botanist Joseph Pitton de Tournefort (1656–1708) is considered "the founder of the modern concept of genera". The scientific name (or

5159-408: 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 a species : see Botanical name and Specific name (zoology) . The rules for the scientific names of organisms are laid down in

5236-424: The species. The optimum temperature also varies by species. Human catalase forms a tetramer composed of four subunits , each of which can be conceptually divided into four domains. The extensive core of each subunit is generated by an eight-stranded antiparallel β-barrel (β1-8), with nearest neighbor connectivity capped by β-barrel loops on one side and α9 loops on the other. A helical domain at one face of

5313-497: 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,

5390-412: 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

5467-403: 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

5544-415: The tube is then tapped on the bench, moving the hydrogen peroxide down until it touches the bacteria. If bubbles form on contact, this indicates a positive catalase result. This test can detect catalase-positive bacteria at concentrations above about 10 cells/mL, and is simple to use. Neutrophils and other phagocytes use peroxide to kill bacteria. The enzyme NADPH oxidase generates superoxide within

5621-566: 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

5698-429: 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

5775-424: The β-barrel is composed of four C-terminal helices (α16, α17, α18, and α19) and four helices derived from residues between β4 and β5 (α4, α5, α6, and α7). Alternative splicing may result in different protein variants. Catalase was first noticed in 1818 by Louis Jacques Thénard , who discovered hydrogen peroxide (H 2 O 2 ). Thénard suggested its breakdown was caused by an unknown substance. In 1900, Oscar Loew

5852-611: Was created by Lehmann and Neumann in 1896 as a taxonomic group to contain the bacterial rods responsible for causing diphtheria. The genus was defined based on morphological characteristics. Based on studies of 16S rRNA , they have been grouped into the subdivision of Gram-positive Eubacteria with high G : C content, with close phylogenetic relationships to Arthrobacter , Mycobacterium , Nocardia , and Streptomyces . The term comes from Greek κορύνη, korýnē 'club, mace, staff, knobby plant bud or shoot' and βακτήριον, baktḗrion 'little rod'. The term "diphtheroids"

5929-415: Was the first to give it the name catalase, and found it in many plants and animals. In 1937 catalase from beef liver was crystallized by James B. Sumner and Alexander Dounce and the molecular weight was measured in 1938. The amino acid sequence of bovine catalase was determined in 1969, and the three-dimensional structure in 1981. While the complete mechanism of catalase is not currently known,

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