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Staphylococcus Lugdunensis
''Staphylococcus lugdunensis'' is a coagulase-negative member of the genus ''Staphylococcus'', consisting of Gram-positive bacteria with spherical cells that appear in clusters. History It was first described in 1988 after being differentiated through DNA analysis. Its name comes from ''Lugdunum'', the Latin name for Lyon, France, where the organism was first isolated. Description Colonies of ''S. lugdunensis'' are usually hemolytic, sticky, yellow or tan, and about 2–4 mm in diameter after a 48-hour incubation. They also can have a characteristic sweet, hay-like odor. ''S. lugdunensis'' may produce a bound coagulase (that is, the enzyme is bound to the cells), a property it shares with ''S. aureus'', but unlike ''S. aureus'', it does not produce a free coagulase. In the laboratory, it can give a positive slide-coagulase test but a negative tube-coagulase test. It is fairly easy to identify because, unlike the great majority of staphylococci, it decarboxylates ornithin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Coagulase-negative
Coagulase is a protein enzyme produced by several microorganisms that enables the conversion of fibrinogen to fibrin. In the laboratory, it is used to distinguish between different types of ''Staphylococcus'' isolates. Importantly, '' S. aureus'' is generally coagulase-positive, meaning that a positive coagulase test would indicate the presence of ''S. aureus'' or any of the other 11 coagulase-positive ''Staphylococci''. A negative coagulase test would instead show the presence of coagulase-negative organisms such as '' S. epidermidis'' or '' S. saprophyticus''. However, it is now known that not all ''S. aureus'' are coagulase-positive. Whereas coagulase-positive staphylococci are usually pathogenic, coagulase-negative staphylococci are more often associated with opportunistic infection. It is also produced by ''Yersinia pestis''. Coagulase reacts with prothrombin in the blood. The resulting complex is called ''staphylothrombin'', which enables the enzyme to act as a protease to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Staphylococcus
''Staphylococcus'', from Ancient Greek σταφυλή (''staphulḗ''), meaning "bunch of grapes", and (''kókkos''), meaning "kernel" or " Kermes", is a genus of Gram-positive bacteria in the family Staphylococcaceae from the order Bacillales. Under the microscope, they appear spherical ( cocci), and form in grape-like clusters. ''Staphylococcus'' species are facultative anaerobic organisms (capable of growth both aerobically and anaerobically). The name was coined in 1880 by Scottish surgeon and bacteriologist Alexander Ogston (1844–1929), following the pattern established five years earlier with the naming of '' Streptococcus''. It combines the prefix "staphylo-" (from ), and suffixed by the (from ). Staphylococcus was one of the leading infections in hospitals and many strains of this bacterium have become antibiotic resistant. Despite strong attempts to get rid of them, staphylococcus bacteria stay present in hospitals, where they can infect people who are most at ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gram-positive
In bacteriology, gram-positive bacteria are bacteria that give a positive result in the Gram stain test, which is traditionally used to quickly classify bacteria into two broad categories according to their type of cell wall. The Gram stain is used by microbiologists to place bacteria into two main categories, gram-positive (+) and gram-negative bacteria, gram-negative (−). Gram-positive bacteria have a thick layer of peptidoglycan within the cell wall, and gram-negative bacteria have a thin layer of peptidoglycan. Gram-positive bacteria retain the crystal violet stain used in the test, resulting in a purple color when observed through an optical microscope. The thick layer of peptidoglycan in the bacterial cell wall retains the Stain (biology), stain after it has been fixed in place by iodine. During the decolorization step, the decolorizer removes crystal violet from all other cells. Conversely, gram-negative bacteria cannot retain the violet stain after the decolorization ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lyon
Lyon (Franco-Provençal: ''Liyon'') is a city in France. It is located at the confluence of the rivers Rhône and Saône, to the northwest of the French Alps, southeast of Paris, north of Marseille, southwest of Geneva, Switzerland, northeast of Saint-Étienne. The City of Lyon is the List of communes in France with over 20,000 inhabitants, third-largest city in France with a population of 522,250 at the Jan. 2021 census within its small municipal territory of , but together with its suburbs and exurbs the Lyon Functional area (France), metropolitan area had a population of 2,308,818 that same year, the second largest in France. Lyon and 58 suburban municipalities have formed since 2015 the Lyon Metropolis, Metropolis of Lyon, a directly elected metropolitan authority now in charge of most urban issues, with a population of 1,424,069 in 2021. Lyon is the Prefectures in France, prefecture of the Auvergne-Rhône-Alpes Regions of France, region and seat of the Departmental co ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Coagulase
Coagulase is a protein enzyme produced by several microorganisms that enables the conversion of fibrinogen to fibrin. In the laboratory, it is used to distinguish between different types of ''Staphylococcus'' isolates. Importantly, '' S. aureus'' is generally coagulase-positive, meaning that a positive coagulase test would indicate the presence of ''S. aureus'' or any of the other 11 coagulase-positive ''Staphylococci''. A negative coagulase test would instead show the presence of coagulase-negative organisms such as '' S. epidermidis'' or '' S. saprophyticus''. However, it is now known that not all ''S. aureus'' are coagulase-positive. Whereas coagulase-positive staphylococci are usually pathogenic, coagulase-negative staphylococci are more often associated with opportunistic infection. It is also produced by '' Yersinia pestis''. Coagulase reacts with prothrombin in the blood. The resulting complex is called ''staphylothrombin'', which enables the enzyme to act as a protease ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Enzyme
An enzyme () is a protein that acts as a biological catalyst by accelerating chemical reactions. The molecules upon which enzymes may act are called substrate (chemistry), substrates, and the enzyme converts the substrates into different molecules known as product (chemistry), products. Almost all metabolism, metabolic processes in the cell (biology), cell need enzyme catalysis in order to occur at rates fast enough to sustain life. Metabolic pathways depend upon enzymes to catalyze individual steps. The study of enzymes is called ''enzymology'' and the field of pseudoenzyme, pseudoenzyme analysis recognizes that during evolution, some enzymes have lost the ability to carry out biological catalysis, which is often reflected in their amino acid sequences and unusual 'pseudocatalytic' properties. Enzymes are known to catalyze more than 5,000 biochemical reaction types. Other biocatalysts include Ribozyme, catalytic RNA molecules, also called ribozymes. They are sometimes descr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ornithine
Ornithine is a non-proteinogenic α-amino acid that plays a role in the urea cycle. It is not incorporated into proteins during translation. Ornithine is abnormally accumulated in the body in ornithine transcarbamylase deficiency, a disorder of the urea cycle. The Moiety (chemistry), moiety derived from ornithine is called ornithyl. Role in urea cycle L-Ornithine is one of the products of the action of the enzyme arginase on L-arginine, creating urea. Therefore, ornithine is a central component of the urea cycle, which enables the disposal of excess nitrogen. Ornithine itself is recycled and, in a sense, acts as a catalyst. First, ammonia is converted into carbamoyl phosphate () by carbamoyl phosphate synthetase. Ornithine transcarbamylase then catalyzes the reaction between carbamoyl phosphate and ornithine to form citrulline and phosphate (Pi). Another amino group is contributed by aspartate, leading to the formation of arginine and the byproduct fumarate. The resulting arginine ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Staphylococcus Hominis
''Staphylococcus hominis'' is a coagulase-negative member of the bacterial genus ''Staphylococcus'', consisting of Gram-positive, spherical cells in clusters. It occurs very commonly as a generally harmless commensal on human and animal skin and is known for producing thioalcohol compounds that contribute to body odour. Like many other coagulase-negative staphylococci, ''S. hominis'' may occasionally cause infection in patients whose immune systems are compromised, for example by chemotherapy or predisposing illness. Description Colonies of ''S. hominis'' are small, usually 1–2 mm in diameter after 24 hours' incubation at 35 °C, and white or tan in colour. Occasionally, strains are resistant to novobiocin and may be confused with other resistant species (e.g. '' S. saprophyticus''). It is one of only two species of ''Staphylococcus'' to display sensitivity to desferrioxamine, the other being '' S. epidermidis''. Unlike ''S. epidermidis'', ''S. hominis'' produces ac ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Staphylococcus Aureus
''Staphylococcus aureus'' is a Gram-positive spherically shaped bacterium, a member of the Bacillota, and is a usual member of the microbiota of the body, frequently found in the upper respiratory tract and on the skin. It is often positive for catalase and nitrate reduction and is a facultative anaerobe, meaning that it can grow without oxygen. Although ''S. aureus'' usually acts as a commensal of the human microbiota, it can also become an opportunistic pathogen, being a common cause of skin infections including abscesses, respiratory infections such as sinusitis, and food poisoning. Pathogenic strains often promote infections by producing virulence factors such as potent protein toxins, and the expression of a cell-surface protein that binds and inactivates antibodies. ''S. aureus'' is one of the leading pathogens for deaths associated with antimicrobial resistance and the emergence of antibiotic-resistant strains, such as methicillin-resistant ''S. aur ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Commensal
Commensalism is a long-term biological interaction (symbiosis) in which members of one species gain benefits while those of the other species neither benefit nor are harmed. This is in contrast with mutualism, in which both organisms benefit from each other; amensalism, where one is harmed while the other is unaffected; and parasitism, where one is harmed and the other benefits. The commensal (the species that benefits from the association) may obtain nutrients, shelter, support, or locomotion from the host species, which is substantially unaffected. The commensal relation is often between a larger host and a smaller commensal; the host organism is unmodified, whereas the commensal species may show great structural adaptation consistent with its habits, as in the remoras that ride attached to sharks and other fishes. Remoras feed on their hosts' fecal matter, while pilot fish feed on the leftovers of their hosts' meals. Numerous birds perch on bodies of large mammal herb ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Osteomyelitis
Osteomyelitis (OM) is the infectious inflammation of bone marrow. Symptoms may include pain in a specific bone with overlying redness, fever, and weakness. The feet, spine, and hips are the most commonly involved bones in adults. The cause is usually a bacterial infection, but rarely can be a fungal infection. It may occur by spread from the blood or from surrounding tissue. Risks for developing osteomyelitis include diabetes, intravenous drug use, prior splenectomy, removal of the spleen, and trauma to the area. Diagnosis is typically suspected based on symptoms and basic laboratory tests as C-reactive protein and erythrocyte sedimentation rate. This is because plain radiographs are unremarkable in the first few days following acute infection. Diagnosis is further confirmed by blood tests, medical imaging, or bone biopsy. Treatment of bacterial osteomyelitis often involves both antimicrobials and surgery. Treatment outcomes of bacterial osteomyelitis are generally good when t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Arthritis
Arthritis is a general medical term used to describe a disorder that affects joints. Symptoms generally include joint pain and stiffness. Other symptoms may include redness, warmth, Joint effusion, swelling, and decreased range of motion of the affected joints. In certain types of arthritis, other organs such as the skin are also affected. Onset can be gradual or sudden. There are several types of arthritis. The most common forms are osteoarthritis (most commonly seen in weightbearing joints) and rheumatoid arthritis. Osteoarthritis usually occurs as an individual ages and often affects the hips, knees, shoulders, and fingers. Rheumatoid arthritis is an autoimmune disorder that often affects the hands and feet. Other types of arthritis include gout, lupus, and septic arthritis. These are inflammatory based types of rheumatic disease. Early treatment for arthritis commonly includes resting the affected joint and conservative measures such as heating or icing. Weight Weight ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
