Coiform+Bacteria

Coliform bacteria are rod-shaped organisms that ferment lactose with the production of acid and gas when incubated at 35-37°C. Although they are most commonly found in the feces of warm-blooded animals, they can also be found in aquatic environments. They wash into aquatic environments during rainfalls, snow melts or other types of precipitation. Leaking septic tanks and sewer pipes also lead to water contamination. Escherichia coli (//E. coli//) is a member of the coliform group that is unique in its ability to ferment lactose at up to 49°C (although optimal growth occurs at 37°C). Because //E.coli// are almost exclusively found in feces, their presence is an indication of fecal contamination. //E.coli// live in the intestines of humans (and other warm-blooded animals) where they help the body break down and digest food. //E.coli// bacteria can transfer DNA via bacterial conjugation (the transfer of genetic material between bacteria through direct cell-to-cell contact), transduction or transformation. This allows genetic material to spread horizontally (when an organism transfers genetic material to another cell that is not its offspring) through an existing population. It is probably through this process that shiga toxin (from //E. coli// O157:H7) spread. //E. coli// O157:H7 is a strain of //E.coli// that produces a powerful toxin that can cause severe illness: bloody diarrhea, cramps, vomiting and nausea. The maximum containment level for //E.coli// is 5.0%.¹ Treatments for coliform contamination include: filtration, chlorination, ultraviolet irradiation, ozonation, iodination and pasteurization.
 * __Introduction__**

__** Objective **__ The primary objective of our project was to see if there was any coliform bacteria in various locations at flat rock brook and if there was, how much. We then expanded on our original objective and explored whether or not coliform levels had any relationship with pH or water temperature. Since the presence of coliform in bodies of water reflect runoff and contamination, it is important to study coliform when determining the cleanliness of a body of water.

__** Methods and Materials **__ Materials: pH meter, jars/water bottles, forceps, air vacuum, beaker, coliform food, filter, forceps, petri dish, incubator, our brains Methods: (Gabriella collecting data) ²  ³    **__Observations__**
 * For Collecting Data:** We collected data from two different spots in flat rock brook: the quarry pond and before the dam. Each time we gathered water samples, we recorded the air temperature, water temperature and the pH. We held the water in water bottles and jars and stored the samples in a refrigerator until testing.
 * For Detecting //E.coli//:** First,100mL of the sample water was measured. A pump was then used to suck out all of the water so that the filter could catch the bacteria and sediment. Food was then dripped onto the filter which was then sealed in a petri dish. The petri dish was left in an incubator at 37°C for around 24 hours. The petri dish was then removed from the incubator and, using the gird on the filter paper, the colonies of different bacterias were counted. Each color represented a different type of bacteria, but we were only concerned with the red dots, which were //E.coli.//

**Quarry Pond** //Februrary 13, 2008:// The pond water was green, murky, and stagnant. The surface of the water was mostly covered with green algae growth. When gathering the water, we noticed that it had a pungently fishy odor that was unpleasant. It is important to note that it was drizzly out and had rained the day before. We took the water back to the classroom and performed the tests to detect the presence of //E.coli.// Once we came back to view the results two days later, we noticed that some sort of fuzzy fungus was growing on the top of the sample. It is likely that some of the algae or another type of plant or bacteria had remained in the water and grown overnight. The sample was not obscured however, and we observed many multicolored dots as explained in the Data section.

//April 20, 2008:// The pond water was still a murky green but was covered by even more algae growth. Almost the entire surface of the water was covered with algae. The water had an even stronger fishy smell that was repugnant. However, we waited too long to perform the tests on the water, and our results have been excluded.

//February 13, 2008:// The water before the dam was brown and muddy. There was quite a lot of sediment in the water, and it was difficult to climb down to the bank in order to get a sample that did not have too much sediment in it. The water had an unpleasant stench surrounding it, and fleas and mosquitoes were prevalent. When we did our tests, there was too much sediment to be able to count the colonies! Next time we would make sure to get a sample from deeper water away from the banks to avoid getting so much sediment.
 * Lake before the Dam**

//April 20, 2008:// There was more water in the lake than the previous time we had been there. The water was less murky and more clear, and seemed to have a more bearable smell.

¹http://www.epa.gov/safewater/contaminants/ecoli.html ²http://www.sciencehound.com/science_project_community/images/e3abd7548047454dd2154113c0e133ce-5333.gif ³[|http://images.google.com/imgres?imgurl=http://www.oxoid.com/bluePress/uk/en/images/pr008703.jpg&imgrefurl=] [|http://www.oxoid.com/UK/blue/press/press.asp%3Fart%3DY%26arch%3DY%26pRef%3Dpr008703%26c%3DUK%] [|26lang%3DEN%26yr%3D2003&h=298&w=300&sz=17&hl=en&start=10&um=1&tbnid=dbdoBOlMCdH8LM:&tbnh=115&tbnw] [|=116&prev=/images%3Fq%3De.coli%26um%3D1%26hl%3Den%26rlz%3D1G1GGLQ_ENUS269%2]** Data, Results, Analysis **