Escherichia Coli And Its Effects On The Physiology, Morphology, Membrane, And Antimicrobic Sensitivity

This lab experiment was done for the purpose of learning how to determine a gram negative bacterium based on multiple tests learned throughout the semester. My gram negative unknown bacterium given to me was Salmonella typhimurium based off of the following tests; Triple Sugar Iron Agar (TSIA), Sulfate Indole Motility (SIM), Methyl Red (MR), Voges-Proskaur (VP), Citrate, Urea Hydrolysis, and Gelatin Hydrolysis. Each test performed gives results such as motility, acid production, fermentation, carbon requirements, or detection of certain coenzymes. With a process of elimination, I determined which bacteria it was not and which bacterium I had, S. typhimurium. The expectation was to master the techniques for each test and utilize the results to determine the unknown bacterium I was given within a two-week period.

The main idea of this experiment was to correctly identify the unknown bacteria, #3. Identification of unknown bacteria yields multiple benefits in many different areas in the research of microorganisms. In this experiment I performed many different test dealing with things such as the presence of enzymes, fermentation abilities and different chemical reactions. Observations made from the tests were then compared to a gram negative unknown chart in order to identify the bacteria. Based off of my results and the chart, I concluded the bacteria #3 was the bacteria Escherichia coli. E. coli is most commonly found in the intestines of warm blooded organisms. Most E. coli strands are non pathogenic however, there are strands

Escherichia coli are rod shaped, gram negative bacteria often found in the gut of humans and other warm-blooded mammals (Jacques & Ngo, 2004). It is transmitted primarily through faecal contaminated food and water. Most strains of E. coli are not harmful to humans, however some strains are pathogenic and can cause symptoms including diarrhoea (Unknown, 2012).

The variety of bacteria that lives in our world today is endless. With variety of bacteria comes a numerous amount of adaptations and enhancements that the bacteria develops, including antibiotic resistance. Escherichia coli, better known as E.coli, is a gram-negative bacteria with several different types of clones with a variety of effects. E.coli often enters the intestinal tract as soon as an infant is born and some forms of it are not pathogenic but rather beneficial to the body(Kaper et al, 2004). When infected with pathogenic E.coli, the body often responds, depending of the type of pathogenic E.coli, with diarrhea, vomiting, upset stomach. etc. The rate at which E.coli is adapting, is creating a much more difficult job to find antibiotics that can eliminate the growth of this bacteria (Tadasse et al., 2002).

Microorganisms have the ability to live everywhere and can survive when put together with another not of its kind. Expectations for this experiment would to successfully obtain credible information behind the mixed unknown and be able to isolate both the gram-negative and gram-positive bacterium. In order to obtain the correct test results and to ensure the right gram mixed unknown is identified there had to be a series of eight biochemical tests performed on the gram-negative bacterium and five biochemical tests performed on the gram-positive bacterium.

In order to isolate fecal coliforms, Eosin Methylene Blue agar, which contains peptone, lactose, sucrose, and the dyes eosin Y and methylene blue, is used. These sugars provided encourage growth of fecal coliforms while the dyes inhibit growth of Gram-positive organisms. As a result, EMB agar allows the inoculation of Escherichia coli, Enterobacter aerogenes, Salmonella typhimurium, and Enterococcus faecalis. To identify E. coli strains on EMB agar, the cultivated bacteria must appear green, black, or have colonies with dark centers (5).

One of hundreds of strains of the tiny germ Escherichia coli, E. coli O157:H7 is a newly-visible cause of food carried/held and waterborne sicknesses. Although most strains of E. coli are harmless and live in the intestines of healthy humans and animals, this strain produces a powerful poisonous chemical and can cause extreme illness. E. coli O157:H7 was first recognized as a cause of illness during an outbreak in 1982 traced to contaminated hamburgers. Since then, most infections are believed to have come from eating undercooked ground beef.

E.coli is a rod shaped bacteria that is found to be gram-negative, which is one of the two characteristic a bacteria has the other one being gram-positive. Gram-negative bacteria such as E.coli have thin layer of cell walls being composed by a particular substance called peptidoglycan which offers protection to the cell. Gram-negative bacteria such as E.coli are responsible for many types of infection and are common causes of food-borne diseases. E.coli are commonly found in the lower intestine of warm-blooded animals (A.Hartstock, 2015). It was discovered by a German bacteriologist called Dr Escherich in the human colon in 1885 (About E.coli, 2015). Dr Escherich explains that certain strains of E.coli are harmless, however strains such as

The E-coli is a gram-negative, rod-shaped bacterium. It can grow under aerobic (extra-intestinal) or anaerobic conditions (intestine) and is the predominant facultive organism in human’s GI tract. It belongs to the bacterial family of Enterobacteriaceae. It is an important member of the intestinal human’s micro-flora. It usually adheres to the mucus overlying the large intestine. Nowadays, pathogenic E-coli are classified based on their unique virulence factors. Pathogenic strains of the bacterium cause three different diseases: (8)

Even when a person is living with no roomate or family they can never really be considered living alone. According to John Tuttle at ZME Science there are on average more than 7,000 different species of bacteria in a home. Bacteria are living, unicellular, prokaryotic microorganisms. There are many different species of bacteria. In fact there are around 30,000 species that have been formally named (Dykhuizen). Plus, there can be more than fifty different strains of one bacteria. Species are identified by the certain characteristics or traits of a distinct bacteria or group of bacteria, whereas strains are determined by the disease they cause or lack of disease. Bacterial pathogens are bacteria that cause disease. However, not all bacteria are pathogenic, some bacteria are non-pathogenic and are often helpful to your body. Probiotics are helpful live bacteria, they protect their host and help prevent disease. But just because you find a probiotic bacteria doesn’t mean that entire species of bacteria is probiotic. Meaning you could have both pathogenic and probiotic strains of bacteria in a single species.

The distribution of the different kinds of microbes contains bacteria, fungal and archaea which make up 90% of the cells in the human body. A large number of bacteria live and thrive in the colon and are referred to as the gut flora. These gut flora help in breaking down certain nutrients that the human body could not. Other bacteria which inhabit human skin and various mucosal surfaces contribute to the normal functioning of the human body. However, when these bacteria multiply to the point that the body becomes overwhelmed by their presence, or if they venture into sterile territory they can cause severe, even life-threatening diseases. One such example is the Escherichia Coli (E-Coli) which is normally found in the colon, but can mutate

E. coli is commonly found in the intestines of animals and humans. Actually, E. coli and other bacteria in our intestines is a necessity to help the body grow properly and to remain healthy. Although some strains of E. coli are dangerous one specific strain

The target of section number one in the lab is to develop microbes on a petri dish to show bacterial amplification in distinctive places. The reason of why I did this was to outwardly observe which territory develops the largest and minimum microbes throughout the span of around eight days. Once the experiment was over, I presumed that the lavatory seats were the most dirty in comparison to the rest. The origination that the restroom seats being the most dirty was invigorated by the examination. The motivation behind section number two in the lab is to exhibit how cleaning supplies influence bacterial amplification. I utilized cleaning supplies, for example, purell and hand cleanser. I also utilized Tetracycline and 409. Following 8 days of outwardly inspecting the antibacterial operators do their work, I found that the Tetracycline did kill the most microorganisms on the petri dish, which braced my theory.

4.4 detection of diarrheagenic E. coli virulence factors isolate according to source of water and place.

Acute diarrhoeal diseases among the children are one of the most important problems affecting children in the world, reducing their well-being and creating considerable demand for health services (WHO, 2010). Diarrhoeal diseases are leading cause of preventable death, especially among children aged under five in developing countries. Diarrhoea is defined as a child with loose or watery stool for three or more times during a 24-hour period. The frequency and severity of diarrhoea are provoked by lack of access to enough clean water and sanitary throwing away of human waste, insufficient feeding practices and hand washing; poor housing circumstances and lack of access to sufficient and reasonable health care (Gerald et al., 2001). Escherichia coli (EPEC) is a main cause of diarrhoea in infants and children in addition to pathogens such as Salmonella, Shigella, Yersinia, Vibrio, Campylobacter sp., Entamoeba histolytica, and Giardia lamblia in developing countries (Ahmed et al., 2009). Diarrhoeagenic E. coli is the major cause of gastroenteritis in children in the developing world and is associated with high resistance intensity to antibiotics (Ochoa et al., 2009).