Gram Staining Lab

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Information about the Bacteria Pseudomonas aeruginosa During microbiology lab, an unknown bacteria culture in liquid broth was assigned to be identified by conducting a series of various tests. Nearly twenty different tests were conducted on the bacteria, but the most important of these was Gram staining test, gelatin stab test, and oxidase test. The results of these three tests allowed for the determination of the bacteria genus and species. The first test conducted was Gram staining. In the process of Gram staining, a small amount of the cultured bacteria was fixed on a slide with heat. Next crystal violet was used as the primary stain. After rinsing the primary stain, a mordant, Gram’s iodine, was added. Afterward, the slide was rinsed …show more content…
Bacteria cells are taken from the culture and literally stabbed into a gelatin medium using either an inoculating needle or loop. If the bacteria contains enzymes called proteases, the enzyme will break down the proteins found in the gelatin and will leave a liquid residue in the tube. If the bacteria contains no protease enzymes, no liquid will be formed and the gelatin media will appear unchanged. The bacteria tested created liquid in the tube which proved it was positive for the gelatin stab test and possessed the enzyme protease. Finally, the bacteria was tested for the oxidase test. Oxidase test looks for the presence of an enzyme that allows oxygen to be the terminal electron acceptor in the bacteria’s electron transport chain. The test has an artificial electron acceptor with an indicator that is made to change color from yellow to blue when it is in the presence of oxidase (Brown and Smith pg. 85). The bacteria was tested and produced a blue color on the swab proving it was positive for containing the oxidase …show more content…
It is transferred through contaminated equipment or healthcare providers (“Pseudomonas aeuroginosa in Healthcare Settings” para. 4-5). When infections from the bacteria occur, they can generally be treated with forms of antibiotics. However, there are certain types of this bacteria that have developed a resistance to antibiotics, similar to the ever popular bacteria MRSA (“Pseudomonas aeuroginosa in Healthcare Settings” para. 7-8).
Pseudomonas aeuroginosa naturally occurs in environments such as the soil and water and on occasion can be found living on the surfaces of plants and animals. Even with the frequency it is found, it will only cause infections if it is allowed to get into cells that have already been damaged in some way, in example a cut or other abrasion of the skin (Todar para.1-4). It is a bacteria that requires oxygen to survive, grows best in temperatures thirty-seven degrees

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