Escherichia coli (E. coli) is defined as a gram negative, rod-shaped, facultative anaerobic bacterium that consist of hundreds of different serotypes and is highly versatile. These serotypes range from strains that are harmless and play a vital role in maintaining intestinal function, to strains that contain pathogenic properties that infect the human body and cause distinct signs and symptoms. Pathogenic Escherichia coli strains are capable of causing three common clinical diseases that include sepsis/meningitis, urinary tract infection and enteric diarrhea disease. The pathogenic E. coli is known to be highly diverse, adaptable and contain various virulence factors that affect a wide range of cellular processes. Therefore, pathogenic Escherichia coli is studied extensively in food, mammals, and the environment. Outbreaks of diseases associated with E. coli are common in developed and developing countries, which pose as major public health concern and epidemiologic studies. Commensal isolate (E. coli HS) that commonly inhabits the normal micro flora of the human and animal gastrointestinal. E. coli HS is a bacterium that can be readily grown in a laboratory setting and has genetics that are easily manipulated. This serotype of E. coli HS is O9 and contains many syntenic sequences with other E. coli genomes. E. Coli HS exhibits 94 genes that are unique to its serotype, wile 64 of these genes do not demonstrate functional annotation. Of the unique genes that exhibit functional annotation are associated to the production of the serogroup O9 lipopolsaccharide. This type of e coli can be identified via….. Escherichia coli serotype O1f7:H7 stains which is a strain that is the cause of human food borne illness and outbreaks ... ... middle of paper ... ...ng based on the Kauffman classification system, Pulsed-field gel electrophoresis (PFGE), miltilocutus variable-number tandem repeat analysis (MVLA), multilocus sequence typing (MLST). Pathogenic E. coli can also be categorized phlyogenetically to 5 core groups, defined as A, B1, B2, D, and E, with Shigella toxin forming in different groups. Commensal E. coli that inhabits the normal flora of the lower intestine is grouped in phylogroup A. Based on the variety of colonization and virulence factors linked with each pathotype, there is no a single method that can be utilized to diagnose and detect all pathogenic Escherichia coli strands. Therefore, numerous biochemical tests, molecular approaches and typing methods have been developed to isolate and identify E. coli from other bacteria that inhabit the body and to distinguish the different pathotypes of E. coli.
Making H. pylori a vital microorganism to research in order to expand the study of microbiology and its interaction with humans. According to Blaser, the H. pylori “is a group of extremely varied strains cooperating and competing with one another. They compete for nutrients, niches in the stomach and protection from stresses.” There can be a variety of strains found in a single stomach, and even though they appear identical, their genes are very different.
They can be found anywhere and identifying them becomes crucial to understanding their characteristics and their effects on other living things, especially humans. Biochemical testing helps us identify the microorganism present with great accuracy. The tests used in this experiment are rudimentary but are fundamental starting points for tests used in medical labs and helps students attain a better understanding of how tests are conducted in a real lab setting. The first step in this process is to use gram-staining technique to narrow down the unknown bacteria into one of the two big domains; gram-negative and gram-positive. Once the gram type is identified, biochemical tests are conducted to narrow down the specific bacterial species.
ABSTRACT: Water samples from local ponds and lakes and snow runoff were collected and tested for coliform as well as Escherichia coli. Humans as well as animals come into contact with these areas, some are used for recreational activities such as swimming and some are a source of drinking water for both animals and humans The main goal of this experiment was to see which lakes, snow run off and ponds tested positive for coliform or Escherichia coli and to come up with some reasoning as to why. It was found that the more remote pond with less contact contained the most Escherichia coli. However, another lake that many swim in and use as their drinking water indeed tested positive for a small amount of Escherichia coli. The two samples from the snow showed negative results for both coliform and Escherichia coli and the two more public ponds that aren’t as commonly used as a source of human drinking water but animal drinking water tested in the higher range for coliforms but in the little to no Escherichia coli range. It was concluded that the remote pond should be avoided as it’s not a safe source of drinking water for humans or animals. Other than that, the the other ponds are likely to be safe from Escherichia coli, but coliforms are a risk factor.
Many children around the world , especially in third world countries suffer many bacterial infection of the gastrointestinal system as a result of lack of awareness and the spread of the disease in the less attention to hygiene and the environment . In order to explain this word gastrointestinal tract infection , especially the stomach and intestines , it can result from infection by bacteria or virus or other parasites (1) . Some of the causes of inflammation as a result of eating food poisoning , especially meat and eggs . However , some symptoms of severe cases are headache , nausea , vomiting , general weakness , diarrhea and pain , the illness begins suddenly with high fever , vomiting , abdominal pain and stool liquid to water that may contain some blood and mucus . The result of drought through loss of fluids and salts and lead an alliance with the poisoning to the collapse of the circulatory system in diseases such as cholera (2) . It must be conducted in diagnosing bacterial to find the source of infection because it causes illness and death of millions in the third world and in particularly children as mentioned . In this report will refer to the most common types of bacteria cause gastrointestinal tract infection for example , Shigella , Salmonella , Vibrio and Campylobacter (3) . First of all , Shigella is gram negative , nonmotile , non lactose fermenting and H2S production . There are four important species , S. sonnei , S. flexneri , S. boydii and S. dysenteriae is the most serious . Next is Salmonella which is gram negative as well , non lactose fermenting and production H2S . These species are S. typhi and S. paratyphi found in humans and animals . Finally , Campylobacter is gram negati...
Pasteurella multocida is a zoonotic bacterium that infects a range of hosts such as livestock, poultry, domestic pets, and even humans. (1,2) The bacterium is a small, nonmotile, bipolar staining, gram-negative coccobacillus. (2) Classifications of these microorganisms are based on the bacteria capsule type and lipopolysaccharide antigens. Pasteurella multocida have five distinct carbohydrate polymer capsular types which are A, B, D, E, and F. (3) The lipopolysaccharide antigens classifies Pasteurella multocida into 16 Heddleston serovars that produce different lipopolysaccharide structures that help protects the bacteria from host immune response. (3)
Enteric bacteria are major microorganisms that colonise human’s gastrointestinal tract- a long tube containing specialised sections such as the mouth, oesophagus, stomach, intestines, rectum and the anus. Gut bacteria make up approximately 95 percent of the total cells in the body, with the colon containing the densest microbial communities (Gibson, Rastall and Fuller 2008: 52). Human gastrointestinal tract consists of 100 different prokaryotic species, and with two bacterial species, firmicutes and bacteroicidetes dominating them (Brooker et al. 2011: 559).
E Coli is a pathogenic bacteria that can be in the intestine of warm blooded animals and humans. It can help break down food in the gut, and allows vitamin K to be absorbed. Its full name is Escherichia Coli, and although many strains are harmless, some can cause food poisoning in humans by making harmful chemicals.
Mycobacterium tuberculosis (M. tuberculosis) is the bacterium that causes the disease tuberculosis (TB). A distinctive characteristic of the genus Mycobacteria is the presence of a thick lipid-rich cell wall and resistance to the decolourization step of the gram stain (being acid-fast). The acid-fast characteristic of the M. tuberculosis is the result of a waxy, lipid-rich cell wall. The cell envelope of the tubercle bacilli contains a layer beyond the peptidoglycan which is exceptionally rich in lipids, glycolipids and polysaccharides. The bacterium is gram positive bacillus which is an obligate aerobe, is non-motile, a non-endospore forming and is non-capsulated. The microscopic appearance of M. tuberculosis is seen as straight, slightly curved rods approximately 3 x 0.3µm in size. In liquid culture media, the bacteria usually grow as twisted rope-like pellets known as ‘serpentine cords’. M. tuberculosis is capable of growing on a wide range of enriched culture media such as Lowenstein-Jensen medium or Middlebrook medium. The optimum growth temperature of the pathogenic organsim is 35-37°C and unlike most other mycobacteria, it cannot grow at a temperature of 25°C or 41°C. M. tuberculosis is an airborne pathogen that is transmitted from person to person, usually infecting the respiratory tract through inhalation (Greenwood, et al., 2012).
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.
Hats off to bacteria! This article summarizes that bacteria are good for our body and help us function a lot better. Bacteria live in our guts, in our mouths, and on our skin. Overuse of antibiotics has disturbed the bacterial ecosystem, possibly so much that it is irreversible. In 1999 Lawrence Brandt a professor of medicine and surgery at the Albert Einstein College of medicine had success when trying to help a patient combat diarrhea induced by clostridium difficile. A patient developed diarrhea after taking a course of antibiotics for sinusitis; nothing could shake her C.difficile infection. Brandt reasoned the initial antibiotic treatment had killed gut bacteria that promote digestive health; not knowing which strain to replace, he transplanted stool form her husband. That night she reported marked improvement- for the first time in six months. This procedure has helped patients, but hopefully in the future doctors will be able to administer the particular strain of bacteria that is needed. 99% of the bacteria we harbor are resistant to culture in the lab. It was this impossible to study bacteria until the last decade or so, when DNA sequencing techniques allowed researchers to obtain gene sequences from as little as one bacterial cell. With this researchers found that bacteria cells in our bodies outnumber our human cells. Bacterial exposure throughout our lifetime is needed for our wellbeing, thinking, and functioning, contributing to conditions such as diabetes, obesity, allergies, asthma, and atherosclerosis, as well as to anxiety and mood and cognition disorders. These conditions have become more prominent because of our obsession with sanitation has eliminated the exposure to bacteria humans used to routinely get throu...
Among hospitalized patients around the world, Clostridium difficile is the primary source of infectious diarrhea. Previously, continuously unbalanced intestinal microbiota, usually due to antimicrobials, was deemed a precondition of developing the infection. However, recently, there have been alterations in the biology from virtually infecting the elderly population exclusively, wherein the microbiota in their guts have been interrupted by antimicrobials, to currently infecting individuals within of all age groups displaying no recent antimicrobial use. Furthermore, recent reports have confirmed critical occurrences among groups previously assumed to be of minimal risk—pregnant women, children, and individuals with no previous exposure to antimicrobials, for instance. Unfortunately, this Gram-positive, toxin-producing anaerobic bacterium is estimated to cost US critical care facilities $800 million per year at present, suggesting the need for effective measures to eliminate this nosocomial infection (Yakob, Riley, Paterson, & Clements, 2013).
In the last decade, the number of prescriptions for antibiotics has increases. Even though, antibiotics are helpful, an excess amount of antibiotics can be dangerous. Quite often antibiotics are wrongly prescribed to cure viruses when they are meant to target bacteria. Antibiotics are a type of medicine that is prone to kill microorganisms, or bacteria. By examining the PBS documentary Hunting the Nightmare Bacteria and the article “U.S. government taps GlaxoSmithKline for New Antibiotics” by Ben Hirschler as well as a few other articles can help depict the problem that is of doctors prescribing antibiotics wrongly or excessively, which can led to becoming harmful to the body.
coli was first identified in 1975 but it was not until 1982 that the Center of Disease Control and Prevention knew what caused it. There are several different strains of E. coli. The one that I am going to focus on is Escherichia coli 0157:H7. This certain strain of E. coli is found in the intestines of cows. For every ten thousand people ate least three are affected. Which means that one percent of food poisoning cases is caused by E. coli. It is normally transmitted through food made from the animal itself. Things like raw milk or rare ground beef. E. coli symptoms appear slower than those of food-borne bacteria. The reason why is that the toxins of E. coli are produced in the large intestine. So you will start exhibiting symptoms normally in three days. You will have the cramps and diarrhea but after twenty-four hours’ blood may start to appear in your stool. This should last one to eight day. In some cases, E. coli victims can develop hemolytic- uremic syndrome, which will cause your kidneys to fail and then you will have to receive dialysis the rest of your
The Campylobacter species observed in 1886 from Theodor Escherich in the colonic mucus of infants who had died of “cholera infantum,” but they could not be cultured. (Miliotis & Bier 2003) Mc Fadyean and Stockman in 1909 first isolated Campylobacter fetus from aborted sheep fetuses. (Miliotis & Bier 2003) After that observed that the Campylobacter which called (Vibrio fetusovid), caused septic abortion in cattle. (Miliotis & Bier 2003) This pathogen bacterium starts to create problems dysentery in the cattle.( Miliotis & Bier 2003) In 1957 the King examined people which have bloody diarrhea the reason for the disease is the Campylobacter species. (Miliotis & Bier 2003)The species of Campylobacter are Campylobacter jejuni, Campylobacter coli, Campylobacter lari and Campylobacter fetus. (Miliotis & Bier 2003) The campyloCbacter is Gram-negative thin; (Siegrist 2014) Gram-negative bacteria are bacteria that do not retain the crystal violet dye in the Gram stain protocol. (Miliotis & Bier 2003) Gram-negative bacteria will thus appear red or pink following a Gram stain procedure due to the effects of the counter stain. (Miliotis & Bier 2003) The shape has the Campylobacter is curved and motile rod like S or spiral. (Siegrist 2014) Finally the Campylobacter has single polar flagella at one or both ends and they exhibit a rapid darting motion (Siegrist 2014), like picture1.
Bacterial cells, like plant cells, are surrounded by a cell wall. However, bacterial cell walls are made up of polysaccharide chains linked to amino acids, while plant cell walls are made up of cellulose, which contains no amino acids. Many bacteria secrete a slimy capsule around the outside of the cell wall. The capsule provides additional protection for the cell. Many of the bacteria that cause diseases in animals are surrounded by a capsule. The capsule prevents the white blood cells and antibodies from destroying the invading bacterium. Inside the capsule and the cell wall is the cell membrane. In aerobic bacteria, the reactions of cellular respiration take place on fingerlike infoldings of the cell membrane. Ribosomes are scattered throughout the cytoplasm, and the DNA is generally found in the center of the cell. Many bacilli and spirilla have flagella, which are used for locomotion in water. A few types of bacteria that lack flagella move by gliding on a surface. However, the mechanism of this gliding motion is unknown. Most bacteria are aerobic, they require free oxygen to carry on cellular respiration. Some bacteria, called facultatibe anaerobes can live in either the presence or absence of free oxygen. They obtain energy either by aerobic respiration when oxygen is present or by fermentation when oxygen is absent. Still other bacteria cannot live in the presence of oxygen. These are called obligate anaerobes. Such bacteria obtain energy only fermentation. Through fermentation, different groups of bacteria produce a wide variety of organic compounds. Besides ethyl alcohol and lactic acid, bacterial fermentation can produce acetic acid, acetone, butyl alcohol, glycol, butyric acid, propionic acid, and methane, the main component of natural gas. Most bacteria are heterotrophic bacteria are either saprophytes or parasites. Saprophytes feed on the remains of dead plants and animals, and ordinarily do not cause disease. They release digestive enzymes onto the organic matter. The enzymes breakdown the large food molecules into smaller molecules, which are absorbed by the bacterial cells. Parasites live on or in living organisms, and may cause disease. A few types of bacteria are Autotrophic, they can synthesize the organic nutrients they require from inorganic substances. Autotrophic bacteria are either photosynthetic or Chemosynthetic. The photosynthetic bacteria contain chlorophyll that are different from the plant chlorophyll. In bacterial photosynthesis, hydrogen is obtained by the splitting of compounds other than water.