41-455: 164 Species See List of Clostridium species for complete taxonomy. Clostridium is a genus of anaerobic , Gram-positive bacteria . Species of Clostridium inhabit soils and the intestinal tracts of animals, including humans. This genus includes several significant human pathogens , including the causative agents of botulism and tetanus . It also formerly included an important cause of diarrhea, Clostridioides difficile , which
82-506: A few exceptional cases of more than 50 min recorded in the literature). Clostridia and Bacilli are quite radiation-resistant, requiring doses of about 30 kGy, which is a serious obstacle to the development of shelf-stable irradiated foods for general use in the retail market. The addition of lysozyme , nitrate , nitrite and propionic acid salts inhibits clostridia in various foods. Fructooligosaccharides ( fructans ) such as inulin , occurring in relatively large amounts in
123-832: A number of foods such as chicory , garlic , onion , leek , artichoke , and asparagus , have a prebiotic or bifidogenic effect, selectively promoting the growth and metabolism of beneficial bacteria in the colon , such as Bifidobacteria and Lactobacilli , while inhibiting harmful ones, such as clostridia, fusobacteria , and Bacteroides . List of Clostridium species As of October 2022, there are 164 validly published species in Clostridium , as well as 38 species described but not validly published. Catalase 1DGB , 1DGF , 1DGG , 1DGH , 1F4J , 1QQW 847 12359 ENSG00000121691 ENSMUSG00000027187 P04040 P24270 NM_001752 NM_009804 NP_001743 NP_033934 Catalase
164-619: 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
205-516: 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
246-634: 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
287-471: 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
328-484: 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
369-415: 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
410-603: Is a commercially available polymerase chain reaction (PCR) test kit (Bactotype) for the detection of C. perfringens and other pathogenic bacteria. Clostridium species are readily found inhabiting soils and intestinal tracts. Clostridium species are also a normal inhabitant of the healthy lower reproductive tract of females. The main species responsible for disease in humans are: Several more pathogenic species, that were previously described in Clostridium , have been found to belong to other genera. In general,
451-501: 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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#1732781041234492-566: 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
533-516: 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
574-468: 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
615-434: 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
656-553: 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
697-407: 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
738-410: 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
779-520: 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
820-438: 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
861-423: 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
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#1732781041234902-458: The rumen and the human large intestine. As mentioned before, these clusters are not part of current Clostridium , and use of these terms should be avoided due to ambiguous or inconsistent usage. Species of Clostridium are obligate anaerobe and capable of producing endospores . They generally stain gram-positive , but as well as Bacillus , are often described as Gram-variable, because they show an increasing number of gram-negative cells as
943-413: The also endospore forming genus Bacillus by its obligate anaerobic growth, the shape of endospores and the lack of catalase . Species of Desulfotomaculum form similar endospores and can be distinguished by their requirement for sulfur. Glycolysis and fermentation of pyruvic acid by Clostridia yield the end products butyric acid , butanol , acetone , isopropanol , and carbon dioxide . There
984-434: 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
1025-440: 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
1066-588: The culture ages. The normal, reproducing cells of Clostridium , called the vegetative form, are rod-shaped , which gives them their name, from the Greek κλωστήρ or spindle. Clostridium endospores have a distinct bowling pin or bottle shape, distinguishing them from other bacterial endospores, which are usually ovoid in shape. The Schaeffer–Fulton stain (0.5% malachite green in water) can be used to distinguish endospores of Bacillus and Clostridium from other microorganisms. Clostridium can be differentiated from
1107-485: 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
1148-455: The genus Bacillus . This classification presented problems, however, because the isolate grew only in anaerobic conditions, but Bacillus grew well in oxygen. Circa 1880, in the course of studying fermentation and butyric acid synthesis, a scientist surnamed Prazmowski first assigned a binomial name to Clostridium butyricum . The mechanisms of anaerobic respiration were still not yet well elucidated at that time, so taxonomy of anaerobes
1189-434: 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
1230-440: 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
1271-422: 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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1312-406: 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
1353-502: 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
1394-424: 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
1435-657: The treatment of clostridial infection is high-dose penicillin G , to which the organism has remained susceptible. Clostridium welchii and Clostridium tetani respond to sulfonamides . Clostridia are also susceptible to tetracyclines , carbapenems ( imipenem ), metronidazole , vancomycin , and chloramphenicol . The vegetative cells of clostridia are heat-labile and are killed by short heating at temperatures above 72–75 °C (162–167 °F). The thermal destruction of Clostridium spores requires higher temperatures (above 121.1 °C (250.0 °F), for example in an autoclave ) and longer cooking times (20 min, with
1476-415: 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
1517-424: 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
1558-645: Was originally illustrated in full detail by a rRNA phylogeny from Collins 1994, which split the traditional genus (now corresponding to a large slice of Clostridia ) into twenty clusters, with cluster I containing the type species Clostridium butyricum and its close relatives. Over the years, this has resulted in many new genera being split out, with the ultimate goal of constraining Clostridium to cluster I . "Clostridium" cluster XIVa (now Lachnospiraceae ) and "Clostridium" cluster IV (now Ruminococcaceae ) efficiently ferment plant polysaccharide composing dietary fiber, making them important and abundant taxa in
1599-724: Was reclassified into the Clostridioides genus in 2016. In the late 1700s, Germany experienced several outbreaks of an illness connected to eating specific sausages. In 1817, the German neurologist Justinus Kerner detected rod-shaped cells in his investigations into this so-called sausage poisoning. In 1897, the Belgian biology professor Emile van Ermengem published his finding of an endospore-forming organism he isolated from spoiled ham. Biologists classified van Ermengem's discovery along with other known gram-positive spore formers in
1640-573: Was still developing. In 1924, Ida A. Bengtson separated van Ermengem's microorganisms from the Bacillus group and assigned them to the genus Clostridium . By Bengtson's classification scheme, Clostridium contained all of the anaerobic endospore-forming rod-shaped bacteria, except the genus Desulfotomaculum . As of October 2022, there are 164 validly published species in Clostridium . The genus, as traditionally defined, contains many organisms not closely related to its type species . The issue
1681-415: 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,