Acute Morphology of Streptococcus pyogenes
Abstract: Streptococcus pyogenes is a gram positive coccus bacterium that is extremely common bacteria. This bacterium is part of group A streptococci, which meant that it has a certain type of polysaccharide antigen on its cell surface. It is commonly known as pharyngitis, or strep throat and produces over twenty exotoxins. Even though this bacterium has been around for thousands of years it still has a susceptibility to penicillin and there have only been a few cases of resistance.
Streptococcus pyogenes is a gram positive bacteria that is associated with multiple types of diseases. Streptos means a chain of links and coccus means a round object. Together this describes the shape of Streptococcus pyogenes, a round chain of ten or more cocci, each measuring 0.5 to 0.75 μm in diameter. This bacterium can cause scarlet fever, streptococcal pharyngitis and erysipelas in humans. It is identified mainly by its ability to create β-haemolysis in blood agar plates.
Streptococci can be separated into groups by a polysaccharide antigen that is deep inside the cell wall. The groups are labeled by the letters ranging from A to R, each group represents a different type of organism that it mostly infects. Group A is mainly pathogenic to humans, while group B is found in cattle. Groups C to R infect animals of lesser complexity. Streptococcus pyogenes is part of group A, which means that the polysaccharide antigen is composed of rhamnose and N-acetylglucosamine and its main host is in humans.
The morphology of S. pyogenes is a chain of cocci that are normally in groups of ten and each cocci range in diameter from 0.5 to 0.75 μm. They are nonmotile, which means that they
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have no form of moveme...
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...agar plates. S. pyogenes produces many extracellular products, they are called streptococcal pyrogenic exotoxins and are classified into three serotypes, A-C. SPE B is the most unique of the three and is responsible for multiple diseases, including toxic shock syndrome. This bacteria does have a weak point, almost all streptococci are susceptible to penicillin.
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Works Cited
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Enterococcus faecalis is a genus of gram positive cocci and form short chains or are arranged in pairs. They are nonmotile, facultative anaerobic organisms and can survive in harsh conditions in nature. There are over 15 species of the Enterococcus genus but about 90% of clinical isolates are E. faecalis. E. faecalis is a nosocomial pathogen because it is commonly found in the hospital environment and can cause life-threatening infections in humans. It is a bacterium that normally inhabits the intestinal tract in humans and animals but when found in other body locations it can cause serious infections. The most common sites for E. faecalis infections are the heart, bloodstream, urinary tract, and skin wounds. Due to vancomycin-resistant Enterococci, many antibiotics have been shown ineffective in the treatment. In this paper, I will describe the ecology and pathology of E. faecalis; the antibacterial resistance; treatment; and, what you can do to prevent Enterococcus infection.
Streptococcus pyogenes is thought to live benignly within one in five people, and is thusly one of the most common pathogens among humans. Due to its common
Microbiology with Diseases by Body System (Hardcover) & MasteringMicrobiology, 3rd edition, Bauman, R. W., Benjamin- Cummings Publishing Company, 2012, San Francisco, CA. ISBN 9780321716378. OR
This pathogen, Streptococcus pneumoniae, is a gram-positive coccus that is long shaped and usually seen in groups of pairs (Todar, 2008-2012). This pathogen ranges from o.5-1.25 micrometers, which is pretty small in size (Todar, 2008-2012). It “lacks catalase and ferments glucose into lactic acid” (Todar, 2008-2012). To grow this bacterium in the lab the best way to do it would be to grow it on a blood agar at 37 degrees Celsius and produces a green zone arou...
L. pneumophila belongs to the genus Legionella. This genus also causes Pontiac Fever, a milder illness resembling the flu. Infections by Legionella bacterium, separately or together, is sometimes called legionellosis. L. pneumophila is a ubiquitous organism which thrives in warm, moist places – including water pipes. It is thin, pleomorphic, flagellated and Gram-negative. It is the primary human pathogen of its genus. It does not have endospores or a capsule and morphologically it is a rod-like bacteria. Although, it is considered Gram-negative, it stains poorly because of its lipopolysaccharide outer layer of the outer cell membrane. It is non-acid-fast, aerobic and non-fermentative. It is not pigmented but it is oxidase and catalase positive. Its optimum temperature is around 35 degrees Celsius or 95 degrees Fairinheight and it is capable of surviving temperature ran...
With the earliest recordings coming from the Fifth Century B.C., streptococcus pyogenes, and more frequently, its symptoms have been prevalent among doctors and historians for hundreds of years. The first mentioning of streptococcus pyogenes is to be credited to Hippocrates, in which he describes the relative symptoms of the flesh-eating bacteria in its early stages. Then depicted by Billroth in 1874, patients carrying erysipelas were determined to have this certain bacterial infection. In 1883, the chain-forming bacteria were isolated by Fehleisen; and in the following year, Rosenbach applied the S. pyogenes name. Further advances in hemolytic and non-hemolytic studies were made by Lancefield in the 1930’s, in which the alpha, beta, and gamma subgroups of the hemolytic structures – detailed and defined by Schottmueller and Brown - were divided into serotypes.
Necrotizing fasciitis is caused most commonly by Streptococcus pyogenes, group A streptococcus, which is the same bacteria that causes common strep throat 8.
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Streptococcus mutans is a gram positive cocci shaped bacteria. It is a facultative anaerobes. Streptococcus mutans is found in the oral cavity and now can be found in the heart tissue and valves. Considering the fact that Streptococcus mutans is a facultative anaerobe the bacteria is often found in between your teeth, around your gum line, and on your occlusal surfaces. Streptococcus mutans lives in temperatures that range from eighteen to forty degrees celsius falling into the mesophile category. Streptococcus mutans changes the environment by adhering to a bio-film layer produced on the enamel surface of your teeth from such things including: acidic foods that contain sugars and starch, drinks that contain carbonation and sugars, whiting products, tobacco use, and lack of oral home care. The first virulence factor is dependent on the synthesis of water-soluble glycans from the disaccharide sucrose. By breaking down the glycogen this allows help for bacteria adhere better. Next virulence factor, Streptococcus mutans has the ability to become more acid tolerant and cell to cell communication. Once the bacteria is colonized in the bio-film it starts to produce an acidic environment below a ph of 7.(Kreth, et al., 2008) By doing so, Streptococcus mutans out competes any other organism living on the teeth or in the oral cavity. This leads to the third factor, which displays a production of lactic acid fro...
Streptococcus pneumoniae is a facultative anaerobe, which after performing a Gram-staining appears as blue-black cocci with the lancet shape, mostly in pair...
Kapper, J.B. Nataro, J.P. & Mobley, H.L.T. 2004, "PATHOGENIC ESCHERICHIA COLI", Nature Reviews, vol. 2, pp. 123-140.
Swiatlo, E., & Ware, D. (2003). Novel vaccine strategies with protein antigens of Streptococcus pneumoniae. FEMS Immunology and Medical Microbiology, 38(1), 1-7. Retrieved from http://www.sciencedirect.com/science/article/pii/S0928824403001469 (Accessed December 11, 2013).
Streptococcus pneumoniae ( responsible for causing strep throat and other throat infections ) are spreading throughout communities at an alarming rate, and antibiotics used to treat Streptococcus pneumoniae are becoming increasingly ineffective as a result of the antibiotic being prescribed to so many people so ofte...
Certain structures of bacteria are indispensable for causing sepsis. All sepsis causing bacteria have S-layer and produce capsules, slime layer and biofilm (see tab. ). These structures protect the bacteria in the tissues against phagocytosis, ROS, lytic enzymes, immune complexes, etc., whereas in the bloodstream capsule and slime layer prevent triboelectric charging, attraction and fixation on the surface of erythrocytes, oxidation and killing by the oxygen released from erythrocytes [33 ].
Engelkirk & Burton (1979) state that bacteria can reproduce asexually by simple division of cells and some bacteria reproduce sexually by conjunction. A bacterium is a waste producer of products and secretions. This allows pathogens to invade their hosts to cause disease some of these harmful diseases are Scarlet fever, an acute illness, characterized by a reddish skin rash, which is caused by systematic infection with the bacterium streptococcus. St. Anthony’s Fire is another bacterial disease. “St. Anthony’s Fire which is an acute superficial form of celluitus involving the dermal lymphatic, usually caused by infection with streptococci and chiefly characterized by a peripherally spreading hot, bright red, oedematous.