Identifying Bacteria Essay Example for Free

Identifying bacteria EssayBacteria identification is accomplished in a number of ways. Two common tools microbiologists use to identify uncharted bacteria include divided key and biochemical tests. The dichotomous key is useful when a microbiologist moreover necessitate to know which group an unknown quantity microbe proceeds to on a general level. When a microbiologist needs to identify a specific bacterium, biochemical tests argon used.PART ONE GENERAL BACTERIA acknowledgmentReview the dichotomous key in skeletal system A, the bacterial kinds in bit B, and the Gram speck information below. You will use all three to determine to which major group unknown bacteria belong.Gram Stain ResultsPurple = Gram positiveRed = Gram negativeNeither royal nor red = No cell wall (neither Gram positive nor Gram negative)Review throw C on the following page. engagement Figure C to identify the type of arrangement displayed by the unknown bacteria. Read through the Sample Identifi cation on the following page for an example of how to identify bacterial groups and arrangements use Figures A, B, C, and the Gram stain results.Sample IdentificationAfter performing a Gram stain, you prize the following to a lower place a microscope(Cells are stained red.)Begin with item 1 on the dichotomous key (Figure A). Because the organismsare red, they are not Gram-positive. According to the key, continue to item 3. Because the organism is red (not absorb or another color), it is indeed Gram-negative according to item 3. The key directs you to item 5. Consider the shape of individual cells for item 5. According to Figure B, the shape type is closest to spherical. (Note spherical is circular.) The bacteria belong to the Gram-negative cocci group.Now use Figure C to describe arrangement of bacteria. (The bacteria are not rod- or club-shaped, so focus on the cocci arrangements.) Identify the arrangement that is most prominent. The bacteria are arranged in a diplo- fashion.En ter the group and arrangement in the table.ApplicationUse Figures A, B, C, and Gram stain results to identify group and arrangement of bacteria. Continue to Part Two after finish the table.View from MicroscopeGroup of BacteriaArrangement(stained red)Gram-negative cocciDiplo-(stained purple)(stained purple)(stained red)(stained red)(stained purple)(stained purple)PART TWOCAse theme scenario identify specific bacteria through biochemical testing To gain an understanding of the processes involved with identifying bacteria through biochemical tests, access Chapter 6 of the text in WileyPlus located on the Week one course page. Once in WileyPlus (Chapter 6), select the Bacterial Identification by API link located under the heading, Take Another Look. Once selected, freshen up the information and watch the Flash-animated movie (animation) located within this link. Then, review the following scenario and answer the questions that follow.Case StudyA recent outbreak of food poisoning has occurred in a community. One possible source of contamination may be the produce that is grown and distributed topically at a farmers market. A test sample of some of the produce revealed show of bacterial contamination. The bacteria sample was tested in a microbiology lab and showed the results that follow. The laboratory also performed a Gram stain of the isolated bacteria and ran a number of biochemical tests to aid identification. The biochemical tests were assayed using the Analytical Profile Index (API) 20E system for identification of Enterobacteriaceae and other gram-negative bacteria.Figure 1. Microbiology laboratory results Unknown bacteria present on produce (API Results)Figure 2. API Results of Unknown Bacteria in text FormatGram stainGram-negativeBased on Gram stain results and the knowledge that this bacterium caused foodpoisoning, the laboratory is able to narrow down the possibilities to three bacterial strains.Figure 3 shows the API results Figure3. API Results of Known Bacterial Strains in Text Format Gram stainApplicationCompare the API biochemical test results in Figure 2 (unknown bacteria fromproduce) with API test results in Figure 3 (known bacterial strains identified in the gray boxes on the left). The bacterial strain in Figure 3 that matches Figure 2 will identify the bacterial strain causing illness. Based upon your observations, which of the bacteria in Figure 3 is the most likely cause of the food poisoning outbreak?