Unknown Bacteria Lab Report

The following tests according to the lab manual were performed: gram stain, fermentation tubes, methyl red, vogues proskauer, sulfur, indole, motility and growing it up on MacConkey agar. The gram stain was performed incorrectly the first time. This is because the decolorizer was not on the bacterium slide for long enough, giving a false outcome.

There are many differents ways to identify a bacterial unknown and many different situations where identification would be beneficial. One way to identify bacterial unknowns is to perform biochemical tests. In this experiment multiple biochemical tests were done, by performing these tests on the bacterial unknown received the two different bacteria were then identified. The citrate test is done to test the ability of organisms to use citrate as a carbon source. This test uses Simmons citrate agar, the agar contains sodium citrate as the only carbon source and has bromothymol blue as the pH indicator. The organisms that use citrate as a carbon source use the enzyme to transport the citrate into the cell. The cells converts ammonium dihydrogen

The colonies were smooth, translucent, and had a white brownish color. The Gram stain resulted in Gram positive cocci. After the Gram stain was completed, the bacteria were streaked on a Mannitol-Salt Agar plate and a Catalase test was performed. After these test were completed a Phenol Red Dextrose Fermentation tube was inoculated, and a SIM Tube inoculated.

The next step of the project included preparing a Gram stain to discover the cell shape, arrangement, and if the bacteria is gram positive or

The first step toward identifying this unknown organism was to perform a Gram Stain to differentiate between gram positive and gram negative bacteria. This is an important step because it directs what the next tests will be. My Gram Stain on sample #12 showed that the bacteria was gram negative, however, after receiving the results of the OF glucose, H2S, Citrate, Urease and Motility tests, it was apparent that my Gram Stain was contaminated. I then performed a catalase test which came back negative, so I ordered a Bacitracin disc, Optochin disc and a CAMP test which had to be incubated overnight. After receipt of those test results,

Bacteria are ubiquitous; they can be found on the skin, in the soil, and inside the body. Because of the very nature of this ubiquity, it is important to be able to determine between different strains of bacteria. An example of this is determining the causative agent for a disease so that the patient will be treated with the appropriate antibiotics. It may be important to determine the bacteria in a certain region, because like with enteric bacteria, it is normal to find them in the digestive tract as they are in a symbiotic relationship with our bodies in this area; however, they also cause opportunistic infections in places outside of the digestive tract to our detriment, such as with a urinary tract infection. Some strains of bacteria are common to nosocomial infections, and identifying these bacteria as such helps create the guidelines for healthcare workers in antiseptic technique. All of the morphology and characteristics of each strain of bacteria help us to better understand the role of bacteria in the body as well as helps us understand how they can cause illness, and what treatment regimen to set in place. In lab this semester, a sample of unknown

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 report will go in depth with the tests used, results yielded, and rationale behind each. Procedures: On the first day of the lab, I was presented with an unknown bacteria labeled simply as 6C. I first observed

The main objective was to identify an unknown organism by utilizing skills we learned in our labs this semester. The purpose was to attain the possible identity of the unknown organism by actually performing biochemical tests and staining techniques we learned in lab. After performing and analyzing the results, we were able to use Bergey’s Manual of Systemic Bacteriology as a guideline to narrow down the genus of our organism test by test.

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.

The test showed a clear zone around the colonies thus determining that the bacteria can break down starch meaning it was a positive result. With a positive starch hydrolysis result the next task was to perform a VP. The results from this test came back negative because there was no color change in the broth. My next step was to check for a swollen cell. I found that the cell was swollen looking from the spore stain slide.

The bases of this experiment was to discover the identify of the unknown from three possible specimens: Klebsiella pneumonia, Escherichia coli, and Enterobacter aerogenes. Utilizaing the T streak technique, the bacteria was isolated into pure colonies for further study. The Gram Stain method was used to identity the morhphology of the bacteria such as the shape and whether the bacteria was Gram positive or Gram negative. Biochemical test were also used to help identify the unknown bacteria. The biochemical test used was the Triple Sugar Iron Agar, Sulfur Indole Motility test, Methyl Red test, Voges-Proskauer test, Citrate test, Urease test, and the Gelatin test. After observing the morphology of the bacteria using the Gram Stain method and utilizing all the possible biochemical test, the bacteria was identified to be Enterobacter aerogenes.

Introduction: Having a hands-on academic experience of the different techniques for instance aseptic technique and procedures like gram staining is important characteristics for understanding the concept of learning to identify a type of bacteria. During this lab report each student would be using a variety of lab techniques and process/procedures from the lab course taught from the professor and learned from students this semester. To include, by performing the multiple test with three types of medias the students should be able to administer the methods to identify the unknown bacteria. With the information from results and extra notes assist the students to identifying the unknown bacteria. Lastly the benefits from this type of hands-on

Plate B incubated at 25oC produced a white, opaque, waxy, and spreading bacteria colonies while plate A incubated at 37oC produced a white, thin spreading bacteria colonies (Figure 1.). Gram staining revealed that plate B contained a rod-shaped bacterium having partial pink and purple coloration with endospores. This suggests that the bacteria is a gram positive bacteria. Gram positive bacteria typically have a thick cell wall which traps the crystal violet making them appear purple. Conversely, plate A is a rod-shaped bacterium but with pink coloration.

The next test performed was the citrate slant test. This test is able to tell whether or not the microbe is able to use citrate as a carbon source. The color of my test remained green. This meant that my results were negative. If the microbe were able to use citrate as a carbon source the results would have resulted in a royal blue