Lab Report On Unknown 32

The first test conducted on unknown bacteria 32 was the Gram stain. From this stain, unknown 32 was found to be a Gram-positive cocci. This test eliminated all possible Gram-negative bacteria, Gram-positive rods and Gram-positive spirillium. Next, the endospore test determined whether or not the Gram-positive bacteria contained endospores. With the use of malachite green, steam, and safranin it was found that unknown bacteria 32 did not contain endospores. This eliminated Gram-positive cocci Sporosarcina spp. The oxidase test is a test using an Oxidase swab. The oxidase swab contains a chromagenic reducing agent which donates its electrons to cytochrome c oxidase if it is present. If cytochrome c oxidase is present, the donation of electrons
When unknown 32 was tested with the oxidase test, it was found oxidase negative. The catalase test tests for the presence of catalase which breaks down hydrogen peroxide and oxidase dismutase. A small amount of hydrogen peroxide is dropped onto a slide of unknown 32 and resulted in bubbles. This result shows that unknown 32 is catalase positive since it broke down hydrogen peroxide and oxidase dismutase which resulted in water and oxygen. This eliminated Enterococcus spp. and Streptococcus spp.

After the initial tests were conducted, five more tests were done to narrow down the genera and species. From the provided list of possible unknown genera, the only genus left was Staphylococcus. However Staphylococcus has many species, so test focused on differentiating the many species of Staphylococcus were conducted. First, to confirm that the unknown wasn’t a Micrococcus sp., the bacitracin test was used. This test confirmed that the unknown 32 was a resistant bacitracin resistant bacterium. Since Micrococcus spp. are susceptible bacteria, Micrococcus spp. were eliminated. The next test was the coagulase test which tests for the enzyme coagulase. In the presence of coagulase, fibrinogen in blood is converted to fibrin.