Identifying An Unknown Bacterium Broth Culture

E. coli bacteria normally lies in the intestinal tract of people and animals. In most cases, E. coli is a harmless bacterium and even serves as an essential part of a healthy human intestinal tract. However, there are multiple types of E. coli and some are pathogenic, meaning they can cause illness. Pathogenic E. coli strains are categorized into six pathotypes: STEC, EHEC, ETEC, EPEC, EAEC, EIEC, and DAEC. Pathogenic forms of E. coli bacteria are able to infiltrate, grow and live in a variety of foods and beverages. Once a food or beverage is contaminated and then consumed, the individual who has consumed it is at risk of an E. coli infection.

Controls are especially important when it comes to identifying unknown microbes as it is done within this report. Positive controls serve as a comparison or model of how the performed test should react if the microbe tested is positive. This enables the experimenter to compare results and determine if their culture is positive or negative for the reactions. In contrast, the negative controls serve to model what the test should look like if nothing is done or if the organism tested is negative. For every laboratory exercise performed in this course, there are positive and negative control demonstrations available for students to reference. These are very useful in aiding students when they are determining the result of their unknown culture

An unknown mixed culture was distributed by the Microbiology instructor labeled with a “3”, which was the assigned group number. The group was informed that there were two unknown microorganisms within the tube. Procedures were then completed in a specified order based on methods taught in the laboratory using the assistance of the assigned

A wide variety of processes had been performed to determine what culture had been acquired in class. My group had acquired culture tube unknown #3. We first isolated the bacteria. In this step we took the broth of the unknown #3 and grew it on an agar plate. The first process that had been performed was discontinuous streaking, and continuous streaking to grow the culture for future use in the lab and to have extra to perform a whole variety of test to determine the unknown. The next experiment that had been performed

Escherichia coli O157:H7 causes 73,000 illnesses in the United States annually. A review of E. coli O157 outbreaks reported to Centers for Disease Control and Prevention (CDC) to better understand its epidemiology. E. coli O157 outbreaks revealed that in that period, 49 states reported 350 outbreaks, representing 8,598 cases, 1,493 (17%) hospitalizations, 354 (4%) hemolytic uremic syndrome cases, and 40 (0.5%) deaths. Clinical laboratories began examining more stool specimens for E. coli O157. In 1994, E. coli O157 became a nationally notifiable infection, and by 2000, reporting was mandatory in 48 states. Escherichia coli O157:H7 was first recognized as a pathogen in 1982 during an outbreak investigation of hemorrhagic colitis.

The effects of the E. coli toxin are can be mild diahorrea, abdominal cramps, vomiting and low grade fever.

The objective of this experiment was to identify two unknown bacteria from a mixed culture. Which was done by using the aseptic technique which was very important to avoid any contamination and keeping the workspace clean while culturing bacteria for different tests. To start, I chose a tube which had a solution of mixed culture. I used the flame to sterilize the inoculating loop and dipped it into the tube and streaked for isolation on 2 TSA plates and placed them in an incubator at 37 for 24 hours. Next day I observed the growth of 2 different types of colonies one for each unknown on the two plates. So I picked the best one and labeled it as master plate and discarded the other plate. From the master plate, I subcultured each type of colony

Individual who get the non shiga toxin producing E. coli have a less severe illness, but there is still a chance they may become severely ill with infections or even death. Although this is uncommon for non shiga toxin E. Coli.

For the first day, I received my unknown bacteria number 110 and I stared to observe that tube. The tube has normal color, creamy, and little bit cloudy. First, I made two new slants to get the strong and alive bacteria for further text. One tube was incubated at 250C and other at 370C. Next, I started to do my Gram Stain. After I finished the smear, heat fix, and cover the slide with all chemical, I saw the pink color stick onto the slide. I knew that this bacterium is gram negative. Then, I looked up the slide though the microscope form 10X -> 40X ->oil ->100X. I saw the bacteria which have rod shape with chains and pairs. I want make sure one more time that bacteria are gram negative or positive, so I stared to set up EMB and PEA plates to get the result for the next class.

E. coli or Escherichia coli are a kind of bacteria that affects the intestinal or the digestive system of a human being, which can even lead to death. It is one of the subgroup of fecal coliform bacteria. E. coli O157:H7 is that toxic microorganism or bacteria which causes the intestinal disease in the human beings which is most likely to last about a week. The common symptoms of these diseases are that the patient will have diarrhea with blood (Clermont, Bonacorsi and Bingen 2000). However, the serve cases of this disease may lead to kidney problems, which can lead to death especially when the patient is a child or an elderly person. That is, it can act severely in those patients who have does not have a strong immune system. Some types of E. coli are normally found in the intestines of people and animals

coli bacteria is a type of bacteria that can live in the intestines of animals and humans. However, there are some types of the E. coli bacteria, particularly E. coli 0157:H7, that can cause intestinal infections. Symptoms of this type of infection include dehydration, abdominal cramps, fever and bloody diarrhoea. These symptoms can endure 2-8 days after exposure to the bacteria. Since these symptoms generally resolve after a few days to a week, most cases of E. coli 0157:H7 infection can be treated at home.

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).

Bacteria are identified systematically by using various different techniques and narrow down their species present in an unknown bacterial culture. This is highly usefully in identifying infections correctly and in research regarding microorganism. Laboratories use identification techniques based on primary characteristics and gram stains to carefully identify unknown organism in samples collected (faeces, blood, sputum, mucosal swabs), to determine the cause of infection and define a disease.

The signs or symptoms of E. coli O157:H7. The symptoms begin like three or four days after you are exposed to the bacteria but some people can also feel the effects in like a day to a week. The first symptoms are Diarrhea, which could

Most e coli do not affect people and actually are a very important part of keeping people healthy especially in the intestinal tract. Although there are some e coli that are pathogenic this means that they cause illness this is done either by giving people diarrhoea or illness that is outside the intestinal tract. These types of e coli that cause diarrhoea are usually transmitted through contaminated water ,food, or contact with animals or persons. E coli kill people by causing dehydration from diarrhoea and vomiting. E coli are considered gram negative bacteria. Colonies of e coli are circular in shape as well as having an entire margin it is also raised and size is considered punctiform (small). The texture of the colony is also smooth and the appearance is shiny and is no pigmented (colourless) as well as being