Microbiology Unknown Paper.
Lahela Correa
12/08/2009
Microbiology 140
Matthew Tuthill
Unknown Lab Report
Introduction
There are many reasons for knowing the identity of microorganisms. The reasons range from knowing the causative agent of a disease in a patient, so as to know how it can be treated, to knowing the correct microorganism to be used for making certain foods or antibiotics. This study was done by applying all of the methods that I have been learned so far in the microbiology laboratory class for the identification of an unknown bacterium.
The purpose of this lab was to identify two unknown bacteria cultures using various differential tests. The identification of these unknown cultures was accomplished by separating and differentiating possible bacteria based on specific biochemical characteristics. Whether the tests performed identified specific enzymatic reactions or metabolic pathways, each was used in a way to help recognize those specifics and identify the unknown cultures. The differential tests used to identify the unknown cultures were
Each person in the class was given a heterogeneous broth mixture of 2 microbes. This mixture was streaked onto the following plates: TSA, BAP, MAC, CNA some of which are selective for gram (+) or gram (-) microbes, while others aren’t specific. On the nonspecific TSA plate a large hazy white colonies was formed. On the other hand, there were also small orange colonies fewer in growth.
Isolation onto a BAP would allow for a pure culture of just gram (+) which would be used to carry out the rest of the differential test. Isolation onto TSA/ MAC allowed for the growth of gram (-) and would be used for further test.
Procedure:
The catalase test was performed only on gram (+) bacteria, as this test would not help in differentiating the gram (-) bacteria because all of the possible unknown gram (-) bacteria were catalase positive. This test is used to detect the presence of catalase, which helps to breakdown toxic hydrogen
12/08/2009
Microbiology 140
Matthew Tuthill
Unknown Lab Report
Introduction
There are many reasons for knowing the identity of microorganisms. The reasons range from knowing the causative agent of a disease in a patient, so as to know how it can be treated, to knowing the correct microorganism to be used for making certain foods or antibiotics. This study was done by applying all of the methods that I have been learned so far in the microbiology laboratory class for the identification of an unknown bacterium.
The purpose of this lab was to identify two unknown bacteria cultures using various differential tests. The identification of these unknown cultures was accomplished by separating and differentiating possible bacteria based on specific biochemical characteristics. Whether the tests performed identified specific enzymatic reactions or metabolic pathways, each was used in a way to help recognize those specifics and identify the unknown cultures. The differential tests used to identify the unknown cultures were
Each person in the class was given a heterogeneous broth mixture of 2 microbes. This mixture was streaked onto the following plates: TSA, BAP, MAC, CNA some of which are selective for gram (+) or gram (-) microbes, while others aren’t specific. On the nonspecific TSA plate a large hazy white colonies was formed. On the other hand, there were also small orange colonies fewer in growth.
Isolation onto a BAP would allow for a pure culture of just gram (+) which would be used to carry out the rest of the differential test. Isolation onto TSA/ MAC allowed for the growth of gram (-) and would be used for further test.
Procedure:
The catalase test was performed only on gram (+) bacteria, as this test would not help in differentiating the gram (-) bacteria because all of the possible unknown gram (-) bacteria were catalase positive. This test is used to detect the presence of catalase, which helps to breakdown toxic hydrogen