Catalase Test Lab Report

In March 10, the first procedure that was done was gram staining. The purpose of this procedure was to determine if the unknown bacterium is gram-positive or gram-negative, and also to determine the cell shape. Gram-positive cells will be purple while gram-negative cells will be pink. The methods for the Gram staining method first starts with a fixed smear of the bacterium, covered it with crystal violet for 30 seconds. Afterwards, it should be gently rinsed off with distilled water and be covered again with Gram’s iodine for 10 seconds. Then gently rinse off the Gram’s iodine with distilled water and decolorize it with ethanol. The ethanol should be rinsed off with distilled water again and then be covered with safranin for 30 seconds. The last step would be to rinse off the safranin with distilled water and blot it dry. The results of the bacterium was stained purple, indicating that it is gram-positive, and was cocci shaped. Some sections of the smear were too concentrated, which was hard to identify the shape of the bacteria, while other sections were less concentrated and was easier to analyze the shape. The next step according to the result, will be a catalase test.
Bubbles after the addition of hydrogen peroxide indicate a positive catalase test. The method for the catalase test was to incubate the plate of the bacterium at 35C for 24 to 48 hours. Afterwards, drop hydrogen peroxide on the colonies and observe them for bubbles. Bubbles were formed after the addition of hydrogen peroxide, which indicated that it did produce enzymes that can break down hydrogen peroxide to water and oxygen. The next step according to the previous results, will be a MRVP