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Corynebacterium Diphtheriae
''Corynebacterium diphtheriae'' is the pathogenic bacterium that causes diphtheria. It is also known as the Klebs–Löffler bacillus, because it was discovered in 1884 by German bacteriologists Edwin Klebs (1834–1912) and Friedrich Löffler (1852–1915). The bacteria are usually harmless unless they are infected by a bacteriophage that carries a gene that gives rise to a toxin. This toxin causes the disease. Diphtheria is caused by the adhesion and infiltration of the bacteria into the mucosal layers of the body, primarily affecting the respiratory tract and the subsequent release of an endotoxin. The toxin has a localized effect on skin lesions, as well as a metastatic, proteolytic effects on other organ systems in severe infections. Originally a major cause of childhood mortality, diphtheria has been almost entirely eradicated due to the vigorous administration of the diphtheria vaccination in the 1910s. Diphtheria is no longer transmitted as frequently due to the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Corynebacterium Striatum
''Corynebacterium striatum'' is a bacterium that is a member of the Corynebacterium genus. It is classified as non- diphtheritic. The bacterium is a gram-positive prokaryote that assumes a 'club-like' morphology, more formally known as a corynebacteria structure. It is non-lipophilic and undergoes aerobic respiration and is also a facultative anaerobe it is catalase negative and oxidase positive glucose and sucrose fermenter. It is generally found as a ubiquitous microorganism, and, as a commensal of humans, colonising the nasopharynx. It has recently been recognised as an emerging pathogen although the genus of ''Corynebacterium'' is not usually considered to be pathogenic. Particularly in the context of human disease, ''Corynebacterium striatum'' is generally considered an opportunistic pathogenic, particularly in a nosocomial setting. It has been recorded to infect the skin, upper and lower respiratory tract and even disseminate, resulting in sepsis. Recent interest has been ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
LPSN
List of Prokaryotic names with Standing in Nomenclature (LPSN) is an online database that maintains information on the naming and taxonomy Taxonomy is the practice and science of categorization or classification. A taxonomy (or taxonomical classification) is a scheme of classification, especially a hierarchical classification, in which things are organized into groups or types. ... of prokaryotes, following the taxonomy requirements and rulings of the International Code of Nomenclature of Prokaryotes. The database was curated from 1997 to June 2013 by Jean P. Euzéby. From July 2013 to January 2020, LPSN was curated by Aidan C. Parte. In February 2020, a new version of LPSN was published as a service of the Leibniz Institute DSMZ, thereby also integrating the Prokaryotic Nomenclature Up-to-date service. References External links List of Prokaryotic names with Standing in Nomenclature [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dirty White Pseudomembrane Classically Seen In Diphtheria 2013-07-06 11-07
Dirt is an unclean matter, especially when in contact with a person's clothes, skin, or possessions. In such cases, they are said to become dirty. Common types of dirt include: * Debris: scattered pieces of waste or remains * Dust: a general powder of organic or mineral matter * Filth: foul matter such as excrement * Grime: a black, ingrained dust such as soot * Soil: the mix of clay, sand, and humus which lies on top of bedrock. The term 'soil' may be used to refer to unwanted substances or dirt that are deposited onto surfaces such as clothing. Exhibitions and studies A season of artworks and exhibits on the theme of dirt was sponsored by the Wellcome Trust in 2011. The centrepiece was an exhibition at the Wellcome Collection showing pictures and histories of notable dirt such as the great dust heaps at Euston and King's Cross in the 19th century and the Fresh Kills landfill which was once the world's largest landfill. Cleaning When things are dirty, they are usua ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Corynebacterium Jeikeium
''Corynebacterium jeikeium'' is a rod-shaped, catalase-positive, aerobic species of Actinomycetota in the genus ''Corynebacterium''. ''C. jeikeium'' is pathogenic, typically causing an opportunistic infection seen most frequently in bone marrow transplant patients. ''C. jeikeium'' is usually susceptible to vancomycin and tetracycline. Resistance to macrolide The Macrolides are a class of natural products that consist of a large macrocyclic lactone ring to which one or more deoxy sugars, usually cladinose and desosamine, may be attached. The lactone rings are usually 14-, 15-, or 16-membered. Ma ... antibiotics is often encountered. It can be acquired in hospitals. Its genome has been sequenced. References External linksType strain of ''Corynebacterium jeikeium'' at Bac''Dive'' - the Bacterial Diversity Metadatabase {{Taxonbar, from=Q3694959 Corynebacterium Gram-positive bacteria Bacteria described in 1988 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pyrazinamidase
PncA is a gene encoding pyrazinamidase in ''Mycobacterium'' species. Pyrazinamidase converts the drug pyrazinamide to the active form pyrazinoic acid Pyrazinoic acid is a pyrazinamide metabolite. Possible role in tuberculosis treatment Pyrazinamid is currently used as a treatment for tuberculosis. Mycobacterium tuberculosis converts pyrazinamid into pyrazinoic acid. The use of pyrazinoic acid .... There is a strong correlation between mutations in pncA and resistance of '' M. tuberculosis'' to pyrazinamide. See also * Pyrazinamide References Enzymes Prokaryote genes Tuberculosis {{enzyme-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Corynebacterium Ulcerans
''Corynebacterium ulcerans'' is a rod-shaped, aerobic, and Gram-positive bacterium. Most ''Corynebacterium'' species are harmless, but some cause serious illness in humans, especially in immunocompromised humans. ''C. ulcerans'' has been known to cause diphtheria and diphtheria-like infections in patients. Previously thought to simply be contaminants recovered from diphtheria patients, “coryneform” or “diphtheroids” are now believed to be the ''cause'' of such infections. Disease Increasingly over the past few decades, ''C. ulcerans'' has been recognized as an emerging pathogen in over six countries across the globe including the United States, the United Kingdom, and Japan. '' C. diphtheriae'' is the causative agent of classical diphtheria, and ''C. ulcerans'' has been found to carry the same gene that codes for the diphtheria toxin. After swabbing lesions on a 53-year-old woman in Germany who experienced swelling of her pharynx and who developed a whitish pseudomembran ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Urease
Ureases (), functionally, belong to the superfamily of amidohydrolases and phosphotriesterases. Ureases are found in numerous bacteria, fungi, algae, plants, and some invertebrates, as well as in soils, as a soil enzyme. They are nickel-containing metalloenzymes of high molecular weight. These enzymes catalyze the hydrolysis of urea into carbon dioxide and ammonia: : (NH2)2CO + H2O CO2 + 2NH3 The hydrolysis of urea occurs in two stages. In the first stage, ammonia and carbamic acid are produced. The carbamate spontaneously and rapidly hydrolyzes to ammonia and carbonic acid. Urease activity increases the pH of its environment as ammonia is produced, which is basic. History Its activity was first identified in 1876 by Frédéric Alphonse Musculus as a soluble ferment. In 1926, James B. Sumner, showed that urease is a protein by examining its crystallized form. Sumner's work was the first demonstration that a protein can function as an enzyme and led eventually to t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Catalase
Catalase 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 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 the species. The optimum temperature also varies by species. Structure Human catalase forms ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hoyle's Agar
Hoyle's agar is a selective medium that uses tellurite to differentially select ''Corynebacterium diphtheriae'' from other upper respiratory tract flora. The medium appears cream to yellow colored, and takes the form of a free-floating powder. It is a modification of Neill's medium. Hoyle's tellurite agar contains: The medium inhibits growth of Gram-negative bacteria and many Gram-positive bacteria, and reduction of the tellurite is characteristic of corynebacteria (though not entirely exclusive to them.) Microscopic examination of samples of suspected colonies, using Neisser differential staining Staining is a technique used to enhance contrast in samples, generally at the microscopic level. Stains and dyes are frequently used in histology (microscopic study of biological tissues), in cytology (microscopic study of cells), and in th ..., is required for confirmation. References Microbiological media {{Microbiology-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Löffler's Medium
Löffler's medium is a special substance used to grow diphtheria bacilli to confirm the diagnosis. History In 1887, Friedrich Loeffler devised a culture medium containing horse serum, meat infusion, and dextrose for use in the cultivation of corynebacteria and for differentiating them from other organisms. Perry and Petran suggested modification of the original formulation. Buck, in 1949, described a modified Loeffler's medium for cultivating ''Corynebacterium diphtheriae''. Uses This medium has a variety of uses in microbiological investigations. The current formulation incorporated these later modifications: # The primary value of Loeffler medium is in the growth and morphological characterization of members of the genus'' Corynebacterium''. This formulation enhances the formation of metachromatic granules within the cells of the organisms. # Due to its serum content, Loeffler medium can be used for the determination of proteolytic activities of microorganisms. # The gray-wh ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Volutin Granules
Volutin granules are an intracytoplasmic storage form of complexed inorganic polyphosphate, the production of which is used as one of the identifying criteria when attempting to isolate ''Corynebacterium diphtheriae'' on Löffler's medium. Polyphosphate granules display the metachromatic effect, appearing red when stained with methylene blue. Volutin granules can also be found in the cytoplasm of ''Saccharomyces'', a genus of ascomycete fungi A fungus ( : fungi or funguses) is any member of the group of eukaryotic organisms that includes microorganisms such as yeasts and molds, as well as the more familiar mushrooms. These organisms are classified as a kingdom, separately fr ....Willey, J. M., Sherwood, L. M. and Woolverton, C. J. (2011). Prescott's Microbiology, 8th Ed. McGraw Hill They are characteristic for different species and depend on the age and condition of the culture. Volutin granules (metachromatic or Babes-Ernst granules) are highly refractive, strongly ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
