Microorganism Essay

1710 Words 7 Pages
Materials and method
Microorganisms are classified in to the three domains of life. The organism that is predominately found in our environment is bacteria closely followed by archaea and eukaryote. Although, microorganism might seem similar, they are different interims of their structures, biochemical composition, and the habitat they adopt. Conducting an extensive test on microorganism has many benefits. We can protect our self’s from different types of infectious disease.
In the unknown microorganism label experiment we were given eight different types of microbes on an agar plate. Using the biochemical testes, we were asked to determine the identity of the microorganism. The first step in conducting a successful lab research is taking
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A sample of bacteria was aseptically removed from D4 and inoculated in to HEA, MAC, MSA and starch agars Medias. Simultaneously, TSIA test was performed to determine the fermentation of carbohydrase, gas and hydrogen sulfide. The TSIA test was followed by SIM test. The results from the SIM test showed the bacteria’s fermentation, of indole and motility. The data’s gathered form the microscopic test and biochemical test were not sufficient enough to identify the bacteria. For this reason, an additional test of MRVP, Citrate, urease, and Durham test was conducted. As a result the MRVP test showed the organism ability to ferment suger and produce acid and …show more content…
This specific type of test determines the fermentation of glucose, production of acid, and butylene glycol. After observing the results bacterial sample D4 tested positive for MR by changing color to red. Unfortunately, the PV tested negative because it remained yellow in color. When we contrast this data to the gram negative bacteria’s only E.coli and p vulgaris tested positive for MR. Almost all of the 4 gram negative bacteria’s tested negative for VP test except S marcescens which was positive. Conducting the bio chemical test narrowed my possible candidates of unknown microbes to P. vulgaris and E.coli. In order to differentiate between the E.coli and p vulgaris I employed the urease to determine the organism’s ability to hydrolyze urea using an enzyme called urease. The unknown sample changed the yellow orange medium to a pinkish red color. This means urea was hydrolyzed. In this case E.coli and only shows negative results while the rest of bacteria’s such as pvalgaris, k pneumonia, and S marcescens were positive for urease test. This test was crucial in determining my unknown microbe to be protinouse vulgaris. In order to be certain with my finding I conducted one final test of citrate and oxidase. Citrate test resulted in negative the proving that the bacteria do not survive on citrate as the only Carbone scours. In contrast the oxidase test was positive it shows that elections are transferred in aerobic respiration.

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