Proteus Essay
Proteus mirabilis
The genus Proteus, according to Bergey’s Manual of Determinative Bacteriology, is a group of straight rod Gram negative bacteria around 0.4-0.8 μm in diameter and 1-3 μm in length. In the microscopic test done, it was seen that the unknown culture contained rods that are on the shorter side, thus was identified as bacteria that appear to be coccobacilli. Because of the presence of peritrichous flagella, species included this genus are motile and most strains swarm in periodic cycles, producing a characteristic concentric swarming pattern, or spread in a uniform film over nutrient media solidified with agar or gelatin, which is evident in the streak plates done over the course of a few weeks, the streak plates showing the …show more content…
Like other members of the family Enterobacteriaceae, it is also facultatively anaerobic, and the unknown culture was proven to be as such through the use of Fluid Thioglycollate Broth, or FTB medium. The genus Proteus is known to catabolize glucose and a few other carbohydrates, with the production of acid and usually gas. As for the unknown, it was able to ferment glucose (without the production of gas, as the Durham tube placed inside the PR Glucose was not displaced) and sucrose, but not lactose. The abovementioned genus is also indicated to produce a negative result in oxidase test and a positive result in catalase test, and the unknown produced negative and positive results in those tests, respectively. The genus is also indicated in the Bergey’s manual as having a positive result in the methyl red (MR) test; however, the unknown initially produced a negative result (after adding 8-10 drops of the MR indicator, the unknown’s color changed to a yellow-orange result) which is the sole discrepancy in this report. However, it is possibly important to note that after a short while, the contents of the tube containing the MR test changed back to a shade of red, possibly indicating that the culture is indeed
The genus Proteus, according to Bergey’s Manual of Determinative Bacteriology, is a group of straight rod Gram negative bacteria around 0.4-0.8 μm in diameter and 1-3 μm in length. In the microscopic test done, it was seen that the unknown culture contained rods that are on the shorter side, thus was identified as bacteria that appear to be coccobacilli. Because of the presence of peritrichous flagella, species included this genus are motile and most strains swarm in periodic cycles, producing a characteristic concentric swarming pattern, or spread in a uniform film over nutrient media solidified with agar or gelatin, which is evident in the streak plates done over the course of a few weeks, the streak plates showing the …show more content…
Like other members of the family Enterobacteriaceae, it is also facultatively anaerobic, and the unknown culture was proven to be as such through the use of Fluid Thioglycollate Broth, or FTB medium. The genus Proteus is known to catabolize glucose and a few other carbohydrates, with the production of acid and usually gas. As for the unknown, it was able to ferment glucose (without the production of gas, as the Durham tube placed inside the PR Glucose was not displaced) and sucrose, but not lactose. The abovementioned genus is also indicated to produce a negative result in oxidase test and a positive result in catalase test, and the unknown produced negative and positive results in those tests, respectively. The genus is also indicated in the Bergey’s manual as having a positive result in the methyl red (MR) test; however, the unknown initially produced a negative result (after adding 8-10 drops of the MR indicator, the unknown’s color changed to a yellow-orange result) which is the sole discrepancy in this report. However, it is possibly important to note that after a short while, the contents of the tube containing the MR test changed back to a shade of red, possibly indicating that the culture is indeed