Objectives:
The purpose of this project is to identify two separate microbial organisms from a given list, which are to be inoculated from a mixed broth culture. Multiple tests will be performed in order to eliminate all organisms from the list that do not provide significant results for the identification of the unknown specimens.
Journal Entries:
April 17, 2018. Today we began the unknown project. I obtained the unknown broth tube #15. I used two Tryptic Soy Agar (TSA) plates in order to make a streak plate. The streak plate is used to separate the two different bacterial organisms that were present in the broth. The plates were placed in the incubator at 37C and in 48 hours there should be isolated colonies on the plates.
April 19, 2018. I obtained my TSA plate from the incubator and determined that there were two separate species present due to the size of the colonies. One species had very small colonies and the other species had larger colonies. I inoculated each different species with the aseptic loop technique and made two separate gram stains to determine the gram reaction and shape of the two separate species. I found that the bacteria that formed the smaller colonies are gram negative bacilli, and the bacteria that formed the larger colonies are …show more content…
I started with the gram negative bacillus by performing the nitrate reduction test and the urease test. I chose these two tests because I knew that a positive urease test would indicate that the gram negative bacillus was P. rettgeri, but this test came back negative after I performed two just to make sure that the results were accurate. Also, the nitrate reduction test could have indicated that the gram negative bacillus was P. fluorescens, but the test result was positive after the reagents were added. Now I knew that I could rule out P. rettgeri and P. fluorescens for the gram negative
The purpose of this project is to identify two separate microbial organisms from a given list, which are to be inoculated from a mixed broth culture. Multiple tests will be performed in order to eliminate all organisms from the list that do not provide significant results for the identification of the unknown specimens.
Journal Entries:
April 17, 2018. Today we began the unknown project. I obtained the unknown broth tube #15. I used two Tryptic Soy Agar (TSA) plates in order to make a streak plate. The streak plate is used to separate the two different bacterial organisms that were present in the broth. The plates were placed in the incubator at 37C and in 48 hours there should be isolated colonies on the plates.
April 19, 2018. I obtained my TSA plate from the incubator and determined that there were two separate species present due to the size of the colonies. One species had very small colonies and the other species had larger colonies. I inoculated each different species with the aseptic loop technique and made two separate gram stains to determine the gram reaction and shape of the two separate species. I found that the bacteria that formed the smaller colonies are gram negative bacilli, and the bacteria that formed the larger colonies are …show more content…
I started with the gram negative bacillus by performing the nitrate reduction test and the urease test. I chose these two tests because I knew that a positive urease test would indicate that the gram negative bacillus was P. rettgeri, but this test came back negative after I performed two just to make sure that the results were accurate. Also, the nitrate reduction test could have indicated that the gram negative bacillus was P. fluorescens, but the test result was positive after the reagents were added. Now I knew that I could rule out P. rettgeri and P. fluorescens for the gram negative