What Are Involved To Determine The Identity Of Unknown Number 34?
Abstract Three tests were performed to determine the identity of unknown number 34, a gram stain, citrate utilization test, and a urease detection test. These tests are explained in detail, and the method of performing the tests is described. The tests showed that the bacterium was gram-negative bacilli that did not utilize citrate, and the ability to hydrolyze urea using urease. These results indicate that the identity of unknown number 34 is Proteus mirabilis.
Introduction
Proteus mirabilis is a gram-negative bacillus bacterium. It is found naturally in the human gut flora. However, if P. mirabilis comes into contact with the urinary tract, urinary tract infections can result. Urinary tract infections caused by P. mirabilis are correlated …show more content…
Gram staining is a technique that was invented by Hans Christian Gram in 1882 (Cantey & Doern, 2015). First, a drop of water was placed on a microscope slide. Using a loop and aseptic techniques (working by an open flame to prevent contamination, and sterilizing the loop in the flame until red hot), a small amount of bacteria from the master plate was mixed with the water then streaked onto the slide. The slide was allowed to dry, then the bacteria was heat fixed onto the slide by running it through the flame twice. A clothespin was attached to the slide and the slide was placed on a staining tray. The smear was covered with crystal violet and allowed to stain the bacteria for two minutes. Then, the slide was rinsed with distilled water at an angle, not directly onto the smear. Grams iodine was added to the slide and allowed to sit for one minute and rinsed again with distilled water. Next, the differentiation step occurred (Bartholomew & Mittwer, 1952) using a small amount of alcohol (about 8 drops) rinsed over the slide, followed immediately by rinsing with distilled water. Safranin was then added to the slide and allowed to sit for 30 seconds then rinsed with distilled water. After blotting the slide with bibulous paper, the slide was viewed under the microscope at 1000X magnification. The counterstain Safranin can be substituted for another …show more content…
One possible source of error lies in an extended incubation period. The test was performed on Friday evening, and the results were not observed until Monday morning. Therefore, the incubation period was longer than the recommended 48 hours. However, the amount of time required for a urease detection test to turn positive depends on the bacterial concentration, and the temperature of incubation (Seo et. al, 2015). Therefore, some bacteria could take longer for a positive result. Usually, Proteus species only take about 2-4 hours to show a positive result; however, some strains could take up to 5 days (Bergquist & Searcy, 1963). Furthermore, studies presenting false positive results for urease detection cannot be
Introduction
Proteus mirabilis is a gram-negative bacillus bacterium. It is found naturally in the human gut flora. However, if P. mirabilis comes into contact with the urinary tract, urinary tract infections can result. Urinary tract infections caused by P. mirabilis are correlated …show more content…
Gram staining is a technique that was invented by Hans Christian Gram in 1882 (Cantey & Doern, 2015). First, a drop of water was placed on a microscope slide. Using a loop and aseptic techniques (working by an open flame to prevent contamination, and sterilizing the loop in the flame until red hot), a small amount of bacteria from the master plate was mixed with the water then streaked onto the slide. The slide was allowed to dry, then the bacteria was heat fixed onto the slide by running it through the flame twice. A clothespin was attached to the slide and the slide was placed on a staining tray. The smear was covered with crystal violet and allowed to stain the bacteria for two minutes. Then, the slide was rinsed with distilled water at an angle, not directly onto the smear. Grams iodine was added to the slide and allowed to sit for one minute and rinsed again with distilled water. Next, the differentiation step occurred (Bartholomew & Mittwer, 1952) using a small amount of alcohol (about 8 drops) rinsed over the slide, followed immediately by rinsing with distilled water. Safranin was then added to the slide and allowed to sit for 30 seconds then rinsed with distilled water. After blotting the slide with bibulous paper, the slide was viewed under the microscope at 1000X magnification. The counterstain Safranin can be substituted for another …show more content…
One possible source of error lies in an extended incubation period. The test was performed on Friday evening, and the results were not observed until Monday morning. Therefore, the incubation period was longer than the recommended 48 hours. However, the amount of time required for a urease detection test to turn positive depends on the bacterial concentration, and the temperature of incubation (Seo et. al, 2015). Therefore, some bacteria could take longer for a positive result. Usually, Proteus species only take about 2-4 hours to show a positive result; however, some strains could take up to 5 days (Bergquist & Searcy, 1963). Furthermore, studies presenting false positive results for urease detection cannot be