Discovering which bacteria are responsible for causing infection in a patient is a very helpful tool and allows for accuracy in providing appropriate antibiotic therapy. A technique utilized is called Gram staining. Gram staining is a type of differential staining method meaning that the stains will react differently depending on the bacteria present. This is a good starting point for identifying specific bacteria. In our scenario, Bacillus, Escherichia, or a Mycoplasma is expected to be found. Bacillus bacteria are rod-shaped and may appear in pairs or chains. They are characteristically Gram positive but may become Gram negative with age. Bacillus bacteria is aerobic in nature meaning that it uses oxygen. A unique feature of Bacillus is its …show more content…
The process for staining techniques starts off with readying a specimen. Samples must be attached to the microscope slide and this is done so by smearing a thin layer of the sample over the slide itself. The slide is then swiped through heat briefly for adherence. In Gram staining, crystal violet dye is applied then soon after washed off and covered with a mordant. A mordant is a chemical used to enhance the sample. The next step is another wash, this time with an agent that removes the color from some of the cells of the sample. The decolorizing agent is then washed off and another dye called safranin is applied. Once again the slide is washed off, dried and observed microscopically. Safranin stained cells will show as red or pink in nature. Gram negative bacteria will appear in this form, as red or pink. Gram positive bacteria will retain the blue or purple coloring of the crystal violet dye. Gram negative bacteria is harder to treat because of its outer membrane. This outer membrane is composed of lipopolysaccharides, lipoproteins and phospholipids and acts as a barrier to treatment methods such as antibiotics. Gram positive bacteria do not have this outer membrane and are therefore more easily treated. To determine which bacteria is causing an illness, other factors besides the results of staining are included. These include the shape of the microbe present, the size and arrangement of the bacteria and how many are seen, the determination of other cells present, and the notation of red blood cells or white blood cells. Another form of differential staining is the acid-fast stain. This staining procedure is used to identify Mycobacterium such as in cases of tuberculosis. Another kind of red dye called carbolfuchsin is used instead of the crystal violet and safranin used in the Gram stain. A