Shigella Flexneri: A Comparative Analysis

An unknown bacterium was handed out by Dr. Honer. The appropriate tests were prepared and applied. The first procedure that was done was the gram stain. Under a microscope, if the gram stain is purple, the bacterium is gram positive, if the stain is red, it is gram negative. The next test was the fermentation tests for glucose, sucrose and

The purpose of this lab was to identify an unknown bacteria culture using differential tests. The identification of the unknown culture was accomplished by identifying the bacteria based on its specific metabolic characteristics and morphology. It is suggested that culture 11 is a sample of Enterobacter aerogenes.

A mixed culture of two unknown bacteria was provided by the instructor. The methods used for

The purpose of this study project was to carefully isolate and identify two unknown bacteria from a mixed culture. The ability to properly evaluate biochemical test results is also necessary for the identification to be successful. The goal was to apply all of the methods and techniques that have been learned in the microbiology laboratory course for the proper identification of unknown bacteria. A certain amount of bacteria that were used throughout the course were possible bacteria that could be found in a mixed culture. The bacteria that were identified in the mixed culture were Staphylococcus Aureus and Kocuria Rhizophila.

In a laboratory setting, it often becomes necessary to identify an unknown organism. In this experiment, researchers classified an unidentified bacterium based on its physical structure, colony morphology, optimal conditions and metabolic properties. A Gram stain using crystal violet, iodine, and safranin and a simple stain using methylene blue characterized the organism’s cell wall. Cultural behavior was classified by inoculating the organism onto nutrient agar and incubating it at 37° C for 48 hours, and observing its behavior, as well as using SIM medium to test for motility. Optimal growth temperature was

The purpose of this lab was to identify two unknown bacteria cultures using various differential tests. The identification of these unknown cultures was accomplished by separating and differentiating possible

|MSA Agar |For organisms that are |Isolates for mannitol fermentation |Yellow color change in |Staphylococcus aureus |

This experiment was conducted to find the genus and species of an unknown bacteria prescribed by the lab teacher, which was unknown bacteria GA3 in my case. Identification of unknown bacteria techniques are used on an every day basis to figure out what type of bacteria it is and to find the best method of how to treat a patient with this bacteria (1). All five “I’s” of Microbiology were used in the testing for the unknown culture. Inoculation was used several times to put the unknown culture into agar plates or into biochemical test tubes. After Inoculation of these tubes or plates, they always were placed into the incubator for further growth and development. Isolation was used to make sure we got the correct bacteria we were testing for. After each further isolation, we gram stained the culture and inspected the culture under a microscope to further help in the identification process of the unknown bacteria. Multiple tests were done on the unknown culture to make sure we were confident in what kind of bacteria the unknown was.

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

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 purpose of this study was to identify the unknown bacterium using biochemical tests and various methods that had been learned from previous the microbiology laboratory class. Identifying the unknown bacterium was determined by separating and differentiating possible

In the world of microbiology it is vitally important to be able to discern the identities of microorganisms. Not only is it important in a lab setting but as well as in healthcare in general. Properly identify what strain of bacteria a person has will aid in the proper medicine and dose given. Throughout the semester we have learned about different types of bacteria and certain test that can clearly identify them. The purpose of this lab report is to identify a Gram-positive or Gram-negative bacterium. Using all the knowledge of procedures and lab techniques identify the unknown and discuss all the tests you performed.

In this lab, I learned aseptic technique and how to identify microbes. Utilizing the three different cultures, I was able to identify the characteristics and biochemical characteristics of both bacteria and yeast . The three microorganisms that were used for this task was: Staphylococcus Epidermidis, Escherichia Coli, and Saccharomyces Cerevisiae. Aseptic techniques are important not just in microbiology lab but also in health care. In health care aseptic techniques reduce the chance of infection for the patient while the same techniques in the laboratory prevent contamination of the experiments. Aseptic technique ensures safety and prevents cross-contamination in the lab. It’s vital to isolate a pure culture (a single organism) from a

Shigella is a Gram-negative organism. Transmission occurs via the fecal-oral route or through person to person contact. The symptoms usually appear 1 to 2 days after ingestion and lasted up to 7 days. Shigella is characterized by “bloody diarrhea; fever; and stomach cramps” (Friis & Dworkin, 2010, p 110). Because of their lower infectious doses many people with Shigella are only mildly ill therefore contact with other persons can further transmit the infection (Friis & Dworkin, 2010, p 110). The spread of Shigella from an infected person to another can be avoided by frequently washing hands with soap and warm water. Hand-washing among children should have been supervised to make sure it was done correctly, especially after toileting and activities.

Live Lactobacillus casei Shirota strain, cultured and tested in our laboratory, is added to the tank. The temperature of the tank is then reduced until the contents are at 37°C (body temperature). The solution is allowed to ferment in the tank for 6-9 days or until the numbers of Lactobacillus casei bacteria reach their ideal concentration.