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Volutin
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 from ....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] |
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 d ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cytoplasm
In cell biology, the cytoplasm is all of the material within a eukaryotic cell, enclosed by the cell membrane, except for the cell nucleus. The material inside the nucleus and contained within the nuclear membrane is termed the nucleoplasm. The main components of the cytoplasm are cytosol (a gel-like substance), the organelles (the cell's internal sub-structures), and various cytoplasmic inclusions. The cytoplasm is about 80% water and is usually colorless. The submicroscopic ground cell substance or cytoplasmic matrix which remains after exclusion of the cell organelles and particles is groundplasm. It is the hyaloplasm of light microscopy, a highly complex, polyphasic system in which all resolvable cytoplasmic elements are suspended, including the larger organelles such as the ribosomes, mitochondria, the plant plastids, lipid droplets, and vacuoles. Most cellular activities take place within the cytoplasm, such as many metabolic pathways including glycolysis, and proces ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Inorganic
In chemistry, an inorganic compound is typically a chemical compound that lacks carbon–hydrogen bonds, that is, a compound that is not an organic compound. The study of inorganic compounds is a subfield of chemistry known as '' inorganic chemistry''. Inorganic compounds comprise most of the Earth's crust, although the compositions of the deep mantle remain active areas of investigation. Some simple carbon compounds are often considered inorganic. Examples include the allotropes of carbon (graphite, diamond, buckminsterfullerene, etc.), carbon monoxide, carbon dioxide, carbides, and the following salts of inorganic anions: carbonates, cyanides, cyanates, and thiocyanates. Many of these are normal parts of mostly organic systems, including organisms; describing a chemical as inorganic does not necessarily mean that it does not occur within living things. History Friedrich Wöhler's conversion of ammonium cyanate into urea in 1828 is often cited as the starting point of modern ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Polyphosphate
Polyphosphates are salts or esters of polymeric oxyanions formed from tetrahedral PO4 (phosphate) structural units linked together by sharing oxygen atoms. Polyphosphates can adopt linear or a cyclic ring structures. In biology, the polyphosphate esters ADP and ATP are involved in energy storage. A variety of polyphosphates find application in mineral sequestration in municipal waters, generally being present at 1 to 5 ppm. GTP, CTP, and UTP are also nucleotides important in the protein synthesis, lipid synthesis, and carbohydrate metabolism, respectively. Polyphosphates are also used as food additives, marked E452. Structure Image:Triphosphorsäure.svg, Structure of triphosphoric acid Image:Polyphosphoric acid.svg, Polyphosphoric acid Image:Trimetaphosphat.svg, Cyclic trimetaphosphate Image:Adenosindiphosphat protoniert.svg, Adenosine diphosphate (ADP) The structure of tripolyphosphoric acid illustrates the principles which define the structures of polyphosp ... [...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-whit ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Metachromatic
Metachromasia (var. metachromasy) is a characteristical change in the color of staining carried out in biological tissues, exhibited by certain dyes when they bind to particular substances present in these tissues, called chromotropes. For example, toluidine blue becomes dark blue (with a colour range from blue-red dependent on glycosaminoglycan content) when bound to cartilage. Other widely used metachromatic stains are the haematological Giemsa and May-Grunwald stains that also contain thiazine dyes. The white cell nucleus stains purple, basophil granules intense magenta, whilst the cytoplasms (of mononuclear cells) stains blue. The absence of color change in staining is named orthochromasia. The underlying mechanism for metachromasia requires the presence of polyanions within the tissue. When these tissues are stained with a concentrated basic dye solution, such as toluidine blue, the bound dye molecules are close enough to form dimeric and polymeric aggregates. The light absor ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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 the medical fields of histopathology, hematology, and cytopathology that focus on the study and diagnoses of diseases at the microscopic level. Stains may be used to define biological tissues (highlighting, for example, muscle fibers or connective tissue), cell populations (classifying different blood cells), or organelles within individual cells. In biochemistry, it involves adding a class-specific ( DNA, proteins, lipids, carbohydrates) dye to a substrate to qualify or quantify the presence of a specific compound. Staining and fluorescent tagging can serve similar purposes. Biological staining is also used to mark cells in flow cytometry, and to flag proteins or nucleic acids in gel electrophoresis. Light microscopes are used for viewin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Methylene Blue
Methylthioninium chloride, commonly called methylene blue, is a salt used as a dye and as a medication. Methylene blue is a thiazine dye. As a medication, it is mainly used to treat methemoglobinemia by converting the ferric iron in hemoglobin to ferrous iron. Specifically, it is used to treat methemoglobin levels that are greater than 30% or in which there are symptoms despite oxygen therapy. It has previously been used for treating cyanide poisoning and urinary tract infections, but this use is no longer recommended. Methylene blue is typically given by injection into a vein. Common side effects include headache, vomiting, confusion, shortness of breath, and high blood pressure. Other side effects include serotonin syndrome, red blood cell breakdown, and allergic reactions. Use often turns the urine, sweat, and stool blue to green in color. While use during pregnancy may harm the baby, not using it in methemoglobinemia is likely more dangerous. Methylene blue was first pr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Saccharomyces
''Saccharomyces'' is a genus of fungi that includes many species of yeasts. ''Saccharomyces'' is from Greek σάκχαρον (sugar) and μύκης (fungus) and means ''sugar fungus''. Many members of this genus are considered very important in food production. It is known as the brewer's yeast or baker's yeast. They are unicellular and saprotrophic fungi. One example is ''Saccharomyces cerevisiae'', which is used in making bread, wine, and beer, and for human and animal health. Other members of this genus include the wild yeast ''Saccharomyces paradoxus'' that is the closest relative to ''S. cerevisiae'', ''Saccharomyces bayanus'', used in making wine, and ''Saccharomyces cerevisiae'' var. ''boulardii'', used in medicine. Morphology Colonies of ''Saccharomyces'' grow rapidly and mature in three days. They are flat, smooth, moist, glistening or dull, and cream in color. The inability to use nitrate and ability to ferment various carbohydrates are typical characteristics of ''Sacc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ascomycete
Ascomycota is a phylum of the kingdom Fungi that, together with the Basidiomycota, forms the subkingdom Dikarya. Its members are commonly known as the sac fungi or ascomycetes. It is the largest phylum of Fungi, with over 64,000 species. The defining feature of this fungal group is the " ascus" (), a microscopic sexual structure in which nonmotile spores, called ascospores, are formed. However, some species of the Ascomycota are asexual, meaning that they do not have a sexual cycle and thus do not form asci or ascospores. Familiar examples of sac fungi include morels, truffles, brewers' and bakers' yeast, dead man's fingers, and cup fungi. The fungal symbionts in the majority of lichens (loosely termed "ascolichens") such as ''Cladonia'' belong to the Ascomycota. Ascomycota is a monophyletic group (it contains all descendants of one common ancestor). Previously placed in the Deuteromycota along with asexual species from other fungal taxa, asexual (or anamorphic) ascomycetes ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fungus
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 from the other eukaryotic kingdoms, which by one traditional classification include Plantae, Animalia, Protozoa, and Chromista. A characteristic that places fungi in a different kingdom from plants, bacteria, and some protists is chitin in their cell walls. Fungi, like animals, are heterotrophs; they acquire their food by absorbing dissolved molecules, typically by secreting digestive enzymes into their environment. Fungi do not photosynthesize. Growth is their means of mobility, except for spores (a few of which are flagellated), which may travel through the air or water. Fungi are the principal decomposers in ecological systems. These and other differences place fungi in a single group of related organisms, named the ''Eumycota'' (''true f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
