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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...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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Kaplan, E. L. (2000). Streptococcal Infections (Vol. 1). New York: Oxford University Press.
Todar, K. (2002). Streptococcus pyogenes (Vol. 1). Madison: University of Wisconsin-Madison Department of Bact. Retrieved July 30, 2008, from http://www.textbookofbacteriology.net/streptococcus.html
E. Coli 0157, written by Mary Heersink, is a nerve-racking, adrenaline-filled story of a mother's experience with a then unknown deadly bacteria. The book brings up many reactions in its readers, especially the questioning of the practice of doctors in hospitals. The reader's knowledge base of scientific procedures in emergency centers was widened as well as the knowledge of how to the human body reacts to different agents in its system.
The Gram positive bacteria has been nicknamed Posi. The Gram positive species’ morphology includes having an opaque opacity with a smooth margin. The moisture content of the Gram positive species is shiny and the pigmentation is gold. The Gram positive species grows at an optimal temperature of 37°C. The shape of the Gram positive species is a cocci, with an arrangement of grapelike clusters. The Gram positive species’ size ranges from .5-1.5 µm. Oxygen requirement of the Gram positive species is facultative, and has complete lysis of red blood cells. All results are summarized in Table
Streptococcus pyogenes is a very common bacteria found in humans. It is very transmissible and can be caught through the air via coughing or sneezing. This form of Strep. illness is referred to as Streptococcal pharyngitis, also known as Strep. throat, which can complicate into Scarlet Fever. It is also possible to be infected through abrasions of the skin, which can result in cellulitis, impetigo, or even necrotizing fasciitis. Aside from human to human contact, these bacteria can also be found in unpasteurized milk. There is no vaccine for Streptococcal infections, though antibiotics such as penicillin still work very well against them.
It is not unusual for some healthy women to harbor Group B streptococcus bacteria in their rectum and vagina. These microorganisms do not usually cause disease when few in number, but when they grow in number and colonize these areas, bacterial infection can become severe.
In the documentary, Hunting the Nightmare Bacteria, reporter David Hoffman investigates this new untreatable infection along two individuals and a bacterial virus within a hospital. The first individual Hoffman investigates is Addie Rerecich of Arizona, she was treated for a staph infection with antibiotics, but other complications arise. Addie had a lung transplant, she was given several different antibiotics, but her body became pan-bacteria, non-resistance to the bacteria. Addie’s life was on the edge, she had to be on life support, and finally she received new lungs. The transplant helped Addie but it would take years before could go back to normal before the infection. The second individual is David Ricci; he had his leg amputated in India after a train accident. The antibiotic treatment he received became toxic to his body increasing problems. While in India, he underwent surgery almost every day because of infections he was developing. Back in Seattle, doctors found the NDM-1 resistance gene in his body; NDM-1 gene is resistance to almost all antib...
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...
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.
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...
Being a gram-negative bacterium, L. pneumophila has lipopolysaccharides (LPS) that act as endotoxin within a human host. The presence of a flagella is thought to mediate adherence to human lung cells, thereby causing infection, since flagella-less strains do not cause disease. Once attached to human cells, the organism is engulfed by a macrophage where is utilizes the internal environment to multiply.
Clinical Infectious Diseases, 49(3), 438-443. Doi:10.1086/600391. See full address and map. Medicare.gov/Hospital Compare - The Official U.S. Government Site for Medicare (n.d).
Necrotizing Fasciitis (flesh eating bacteria ) from an essay by Katrina Tram Duong, edited by S.N. Carson M.D.
... and quickly grow. Secondly, invasins help the bacteria spread in the host’s tissues. An invasion is a protein that acts locally to damage host cells to facilitate the growth and spread of the pathogen. More simply, Staphylococcus aureus and Streptococcus pyogens have a small army of invasins that basically attack the host very quickly and spread the bacteria out far – into the blood and organs. Another virulence factor of both Staphylococcus aureus and Streptococcus pyogens is their cellular secretions. The secretions include antigens, enzymes, and toxins that assist with various functions needed to feed the bacteria and fend off the host’s immune defences.
"Bloodborne Pathogens : MedlinePlus Medical Encyclopedia." U.S National Library of Medicine. U.S. National Library of Medicine, n.d. Web. 09 Feb. 2014.
Streptococcal pharyngitis (colloquially known as strep throat) is an infection caused by a Streptococcus pyogenes bacterium, which also forms a category called Group A Beta Hemolytic Strep (GABHS). They are responsible for various diseases, however strep throat is the most epidemic. S. pyogenes is the causative agent of over 10 million of skin and throat infections reported every year.
Ford-Jones, E. L., & Kellner, J. D. (1995). " CHEAP TORCHES": An acronym for congenital and perinatal infections. The Pediatric infectious disease journal, 14(7), 638-639.