Abstract
This report explains in detail the function, structure and assembly of flagella in E.coli and Salmonella, using plain language and a number of diagrams. Movement (chemotaxis) is the primary function of flagella but its design also incorporates efficient repair capability and antigenic variation. In Salmonella and E.coli the flagellar filament is a homopolymer of flagellin monomers, although other species (such as Helicobacter) build their flagella from mixtures of two types of subunit. All the properties of the functioning filament are reflected in the structure of the flagellin monomer, which has conserved and variable regions, regions targeted by chaperones and coiling enzymes and regions evolved specifically for interaction between monomers. Chemotaxis is driven by a proton motive force (as in oxidative phosphorylation) and the basal complex that converts this energy into rapid rotation of the flagellum is highly complex.

From the Paper
"Many bacteria are motile and exhibit chemotaxis migration through the extracellular medium towards attractants (e.g. carbon sources), and away from repellents (e.g. antibiotics). The majority move using flagella protein structures variable in number and position (Box 1) that generate thrust by rotating like propellers. Flagella are 15nm in diameter and can be observed under light microscopy after thick metal staining or using advanced microscopy techniques such as electron microscopy. Because of the competitive advantages of chemotaxis, there has been strong selection for efficient chemotactic apparatus and flagellar efficiency. The flagellum is based in the bacterial surface layers where a complex array of proteins forms the flagellar motor. Resembling the electric rotary motor and the membrane-bound F1F0-ATPase, and powered by a proton influx across the inner membrane, this highly efficient machine is merely 30nm in diameter. Its mechanism is the subject of ongoing research."

Tags:antigenic, apparatus, bacteria, bacterial, chaperones, chemotaxis, coli, cytoplasmic, escherichia, export, flagellin, flagellum, motile, motility, salmonella, variation

Abstract
This paper discusses the bacterium Escherichia coli, the disease that it causes, and how humans can become infected with it. It reports on a test done to determine the percentage of grocery store beef and chicken contaminated with the bacterium and how much of the contaminated meat showed evidence of cytotoxicity and hemolytic activity.

From the Paper
"This paper discusses the bacterium Escherichia coli, the disease that it causes and how humans can become infected with it. It reports on a test done to determine the percentage of grocery store beef and chicken contaminated with the bacterium and how much of the contaminated meat showed evidence of cytotoxicity and hemolytic activity.
"Escherichia coli or E coli is a bacterium that commonly lives in the intestines of people and animals in a non-pathogenic form. (Lee Marks) E coli can..."

Tags:E. coli 0157:H7, hemolytic, cytotoxic, beef, chicken, materials and methods

Abstract
This paper examines the Taco Bell E. coli outbreak, asserting that green onions may not have been the source of contamination after all. The paper concludes with an emphasis on the difficulty of determining the causes of such outbreaks.

From the Paper
"Since the beginning of human agriculture some twenty thousand years ago there have been countless instances of people being infected by produce contaminated with bacteria viruses and other microbes. Until the takeover of small individual farms by huge corporate agricultural conglomerates in the last half of the ... th century most outbreaks of food poisoning were localized. But today... of America's beef is produced by just four companies,... of pre-cut salads come from only two corporations and a third of our national milk supply is produced by..."

Tags:E. coli Outbreaks, food safety, Taco Bell

Abstract
First discovered by Theodor Escherich, E. coli is one of the best understood bacteria. This harmless intestinal inhabitant can become troublesome when it's consumed by fecally contaminated food or drink, or through an insect bite. This paper overviews E. coli and it's filamentous morphology. The association of E. coli and meningitis is as is discussed, as is its relationship to lung infections. Lastly, one of the larger single source outbreaks is briefly reviewed.

Outline:
Escherichia coli Overview
E. Coli's Filamentous Morphology
E. Coli and Meningitis
E. Coli and Lung Infections
E. Coli Outbreak
Conclusion

From the Paper
"Justice, Hunstad, Cegelski, and Hultgren's (2008) research demonstrates one of the many arsenals of tools bacteria have at their disposal - filamentous morphology. The researchers note that uropathogenic E. coli are the predominant cause of urinary tract infections. During acute infection of mammals, the E. coli bacteria invade the superficial epithelial cells in the bladder. They then follow a complex development cycle that the authors state, at this stage, is associated with a morphological plasticity. The bacteria grows to form intracellular bacterial communities. As the community matures, a subpopulation of the bacterial community begins a distinct development program, in which cell division is inhibited. This leads to the formation of filamentous bacteria that can react 70 m in length."

Tags:Meningitis, Lung, Infections, bacteria

Abstract
This paper provides much-needed information on E. coli - a microbe that has garnered a great deal of attention in recent years because of the profusion of e-coli outbreaks. Specifically, the next few pages will offer information with regards to the size, shape, metabolism, cell structure, living environment, reproductive processes, genus and species of E. coli as well as its effects upon humans (the most significant "host" organism of them all). Finally, the paper will look briefly at treatments for e-coli and time will also be set aside for a short diagnosis of the disease. In the final analysis, the E. coli bacillus is a microbe about which much is known - but one which has defied efforts to stamp out its unpleasant impact upon human health.

From the Paper
"The following paper will provide much-needed information on e-coli - a microbe that has garnered a great deal of attention in recent years because of the profusion of e-coli outbreaks (Early, para.1-5). Specifically, the next few pages will offer information with regards to the size, shape, metabolism, cell structure, living environment, reproductive processes, genus and species of e-coli as well as its effects upon humans (the most significant "host" organism of them all). Finally, the paper will look briefly at treatments for e-coli and time will also be set aside for a short diagnosis of the disease. In the final analysis, the ...."

Tags:bacteria, outbreak, treatment

Abstract
This paper explains that the e-coli bacillus is a microbe about which much is known but has defied efforts to stamp out its unpleasant impact upon human health. The author points out that these extraordinarily tiny cells are invisible to the naked human eye and can accumulate in vast quantities in food preparation areas without individuals being aware of them. The paper relates that e-coli cells are prokaryotic and distinguished by a single, circular chromosome; such cells also contain DNA as plasmids. The author states that, in simple cases of e-coli poisoning, rehydration is essential; however, there is no evidence that antibiotics improve the course of the disease and/or expedite recovery and anti-diarrheal agents are strongly discouraged. The paper concludes that this tiny "bug" certainly seems resilient enough to cause human beings misery for some time to come.

From the Paper
"The living environment and the reproductive process of the e-coli cell are also interesting. Simply put, e-coli most commonly flourish in the intestines of warm-blooded animals. In terms of reproduction, the process is simply one of binary fission, with the circular DNA chromosome replicated. The cell splits into two identical cells with each cell having the same DNA; it should be pointed out that, during the fission process, the identical chromosomal material attaches itself to different parts of the cell membrane so that "replicate" material is firmly anchored where it needs to be when the cell begins to pull apart and halve."

Tags:stool, rehydration, uremic, tiny, food, prokaryotic

Abstract
This a detailed, and well researched paper discussing how e. coli can be prepared and used for study of Molecular genetics. The author looks at how e.coli lends is an ideal candidate for this area because it is such a simple organism. The paper also examines how scientists have been immeasurably helped in their progression of learning about the fundamentals of molecular genetics by the fact that E. coli can be induced into competence through a number of methods. The paper includes numerous illustrations.

From the Paper
"Most of us, when we think of Escherichia coli at all, tend not to have very pleasant associations with the organism. It is in fact among the organisms that are most likely to affect (and infect) households. While E. coli is actually an integral part of the normal gastrointestinal flora, certain strains can cause diarrhea, fever and vomiting by one of three ways: by giving off toxins, by directly invading the mucosal lining of the intestinal wall, or by adhering to the intestinal wall. A person infected with E. coli may also have malaise or overall weakness and abdominal cramps. And a new virulent strain of E. coli, which is passed to humans via contaminated and improperly stored or prepared food, can cause a fatal kidney condition a finding that has prompted public health and food industry officials to suggest changes in the meat-inspection process, including the irradiation of some ground beef. But the bad name that E. coli deserves as a very nasty bug that infects humans must be offset by the fact that study of this organism has vastly increased our understanding of the field of molecular genetics. This paper outlines some of the most important basic principles of this field by focusing on the specific findings that studying E. coli have allowed scientists to derive."

Tags:bacteria, genetics molecule molecular geneticsgenes dna rna cell, recombinant

Abstract
The writer points out that the purpose of this laboratory was to acquire fundamental knowledge and experience in microbiological procedures, specifically in growing bacterial colonies on a nutrient medium under controlled conditions. In this case, Escherichia coli (E. coli) bacteria were grown on nutrient agar, contamination was minimized by keeping the surroundings sterile, and all agar plates were incubated. The writer notes that the first part involved making five serial dilutions from a bacterial suspension in order to pinpoint colony numbers. The second experiment compared two methods of spreading bacteria across agar plates using streaks. The goal was to isolate single colonies. Lastly, the third portion of the laboratory involved replicating plates from a master plate in order to isolate strains of mutant bacteria onto different nutrient mediums and determine bacterial auxotrophy to these nutrients.

Outline:
Introduction
Materials and Methods
Results
Discussion
References

From the Paper
"In the streaking experiment, method B proved to be much more effective for isolating single colonies. The different streaking methods may have contributed to the morphological differences between the E. coli on the two plates. There were evident differences in the size and colour. Since method B was dominated by spaced out single colonies, the darker colour and larger size can be attributed to more nutrients being available to each colony, and more room (surface area) for growth. For the same reason, the more crowded groups of bacteria on the method A plate were a lighter colour and generally smaller. Aside from these two differences, the E. coli shared great resemblance, and based on morphology alone, should not be classified as different species. Nonetheless, the only way to determine whether or not two sets of visibly different bacteria are genetically different is to actually observe their DNA."

Tags:microbiological, bacteria, contamination

Abstract
This paper examines the E.Coli outbreak that took place in 1996 when 70 children were found infected with the bacteria after drinking Odwalla's apple juice. The Court heavily penalized the company as it was revealed during FDA investigation that Odwalla was not following proper quality control measures and its products were not being tested for bacterial contamination. Douglas Levin had to take drastic measures to win back the trust of Odwalla's customers.

Abstract
This paper reports on an experiment in which, using sewage water to locate the E.coli bacteriophage, the bacteriophage was isolated from the original culture and placed in an enriched medium to grow and reproduce. The author continues that each one of the plaques represents a viron from the original culture, and, by counting the plaques, they were able to determine the concentration of bacteriophages in the culture. The author reports that findings among the different lab groups differed significantly, but this could be explained by the fact that the experiments were performed on separate days a week apart.

Table of Contents
Abstract
Introduction
Materials and Methods
Results
Discussion

From the Paper
"E.coli was grown for 48 hrs in TSB tubes at 37degrees C by the lab assistant. (Sewage from the Cheney Sewage Works.) The sewage was then centrifuged and the bacteria containing portion was filtered using a 100 mL filter apparatus. I picked up my E.coli and filtered sewage from the lab assistant. Next, I gathered 7 plates of triptocase soy agar. These were labeled 1x10^-3 to 1x10^-9 and placed into the incubator to bring their temperature up to that of the bacteria/phage solution to be added later. 9 Eppendorf tubes were labeled 1x10^-1 to 1x10^-9, these were then set aside. Sterile saline was then gathered and using a Beckman autopipetter. I transferred 900 uL of sterile saline into each Eppendorf tube."

Tags:culture, equipment, reproduction, variation, morphology