Unknown Lab Report April 25th, 2006 Introduction 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 bacteria based on specific biochemical characteristics. Whether the tests performed identified specific enzymatic reactions or metabolic pathways, each was used in a way to help recognize those specifics and identify the unknown cultures. The differential tests used to identify the unknown cultures were oxidase, catalase, lactose and sucrose fermentation, Kugler/iron agar, nitrate reduction, gelatin hydrolysis, starch hydrolysis, manitol salt, MR-VP, citrate, bile esculin, …show more content…
An inverted Durham tube was used again to test for the production of any gas. Adding 10 drops of both sulfanilic acid and á-napththylamine to the medium if the first test to see if nitrite is present. If nitrite is present, the medium turns red, indicating a positive test. However, if the medium does not change, a second test is performed to see if nitrite was further reduced. In this second test, zinc powder is added to the broth to catalyze the reduction of any nitrate present to nitrite. If nitrate is present when the zinc is added the reduction of this compound will cause the medium to turn red, from the previously added reagents. Red medium on the second addition indicates nitrate was not reduced and a negative test result. However, if the medium does not change after the addition of the zinc, the unknown is positive for nitrate reduction, as the nitrite has just been further reduced, preventing its detection. A gelatinase test was performed using nutrient gelatin to determine the ability of the bacteria to produce gelatinases. The gelatin was inoculated with the unknown cultures and incubated. The tubes were then placed on ice to reform the warm gelatin. If the gelatin remained solid after inoculation, the bacteria did not produce the gelatinase enzymes to liquefy the agar, constituting a negative test. However, if the gelatin was liquefied, the enzymes were secreted and the bacteria were positive. A starch test
When the pH is not at its optimum, the differing pH's will disrupt the bonding between the R groups of the amino acid causing its structure and the shape of the activation site to change
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.
The purpose of the lab was to determine the ratio of air to acetylene results in complete combustion of acetylene gas. The balanced chemical equation for this experiment was C2H2(g) + O2(g) --> CO2(g)+ H2O(l). Complete combustion is the reaction of an element or compound with oxygen to produce the most common oxides and energy. Complete combustion occurs when the fuel and oxygen combine in exact proportions to completely burn the fuel, which leaves a clean test tube. Incomplete combustion is the reaction of an element or compound with oxygen to produce some oxides with less oxygen than the most common oxides. Incomplete combustion occurs when there is not enough oxygen to react
The purpose of this lab was to identify two unknown bacteria from a mixed culture. The reason for identification of unknown bacteria was to help students recognize different bacteria through different biochemical tests and characteristics. This is important in the medical field because identification of unknown bacteria can help treat a patient by knowing the contributing source of a disease. Also knowledge of different bacteria helped others make antibiotics used today. This lab was completed by using the methods learned thus far in identification of bacteria.
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.
My unknown organism #6 is Morganella morganii, which is a gram-negative bacillus rods commonly found in the environment and also in the intestinal tracts of humans, mammals, and reptiles as a normal flora. (3, 5) This bacterium Morganella morganii, was first discovered in the 1906 by a British bacteriologist named H. de R. Morgan. (2) Despite its wide distribution, it is an uncommon cause of community-acquired infection and is most often encountered inpostoperative and other nosocomial settings. (2, 3) Morganella morganii infections respond well to appropriate antibiotic therapy; however, its
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
|EMB Agar | |Distinguishes bacteria that ferment |Dark blue colonies with|E. coli and P. |
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.
There are many reasons for knowing the identity of microorganisms. The reasons range from knowing the causative agent of a disease in a patient, so as to know how it can be treated, to knowing the correct microorganism to be used for making certain foods or antibiotics. This study was done by applying all of the methods that have been learned so far in the microbiology laboratory class for the identification of unknown bacteria. The identification process can be completed with a series of deferential stains and biochemical tests. Creating a dichotomous key helps to limit the amount of biochemical tests done on an unknown organism and by observation
groups. It was conducted to further the research in choice overload and paralysis of the mind.
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
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
Table 1 Concentration of protein, DNA, and ratio of the two in heart, kidney and liver of bos taurus. Average standard deviation of protein concentration is also shown.