Bacterial Diversity Lab Report
Bacterial Diversity Project
John FreesackSection A24
Kim Daffer, John Chang
September 23, 2012
Introduction:
Bacteria are everywhere. Some can be seen with the naked eye and some require a microscope but how do we distinguish one kind of bacteria from another? To answer this question, we were required to complete three bacterial labs that helped us to understand what microorganisms are and how to identify and classify them. Thus, the main purpose of this project is to identify our unknown microorganisms, more specifically, our unknown bacteria.
There are many ways to distinguish and classify bacteria. You can distinguish bacteria from other microorganisms by its size. Bacteria are around one micrometer and yeast is 4-40 micrometer …show more content…
Then we performed a KOH string test to see if our unknown bacterium is Gram-positive or Gram-negative. We added a drop of 3% KOH (potassium hydroxide) to the leftover of our colony that we chose earlier to see if the mixture becomes viscous and forms a string. We recorded our observation and moved on to incubating our live culture on the EMB-lactose and PEA. Vancomycin wasn’t available to be used. We added our live culture to the EMB-lactose and PEA and added sterile beads to spread the bacterial cells all over the surfaces of the two agars and removed the beads and incubated the two agars. While the agars were incubating, we prepared our gel and loaded our respectful samples and ran the gel. After the gel finished running, we got a picture of our gel and recorded our observation for later …show more content…
MSA contains a very high concentration of salt that allows only two Gram-positive species to grow: Staphylococcus and Micrococcaceae. Now we are down to two suspects. We know that according to Table 2, our unknown bacterium did grow on MSA but there weren’t any colored zones around the colonies. This means that our unknown bacterium is a non-fermenter. This was confusing at first but Superfarmer’s Weblog confirms it. On their website, they’ve confirmed that Micrococcus luteus (Micrococcaceae) do indeed grow on MSA and it is a non-fermenter thus backing up my believe that Micrococcus luteus is our unknown bacterium. But I also know that you’re saying “Staphylococcus can also grow on MSA too!” and I totally agree but as you can see under the blast result in the “Result” portion of this paper, none of the top blast result had Staphylococcus but they did have Micrococcus luteus which backs up my belief even more that Micrococcus luteus is our unknown
John FreesackSection A24
Kim Daffer, John Chang
September 23, 2012
Introduction:
Bacteria are everywhere. Some can be seen with the naked eye and some require a microscope but how do we distinguish one kind of bacteria from another? To answer this question, we were required to complete three bacterial labs that helped us to understand what microorganisms are and how to identify and classify them. Thus, the main purpose of this project is to identify our unknown microorganisms, more specifically, our unknown bacteria.
There are many ways to distinguish and classify bacteria. You can distinguish bacteria from other microorganisms by its size. Bacteria are around one micrometer and yeast is 4-40 micrometer …show more content…
Then we performed a KOH string test to see if our unknown bacterium is Gram-positive or Gram-negative. We added a drop of 3% KOH (potassium hydroxide) to the leftover of our colony that we chose earlier to see if the mixture becomes viscous and forms a string. We recorded our observation and moved on to incubating our live culture on the EMB-lactose and PEA. Vancomycin wasn’t available to be used. We added our live culture to the EMB-lactose and PEA and added sterile beads to spread the bacterial cells all over the surfaces of the two agars and removed the beads and incubated the two agars. While the agars were incubating, we prepared our gel and loaded our respectful samples and ran the gel. After the gel finished running, we got a picture of our gel and recorded our observation for later …show more content…
MSA contains a very high concentration of salt that allows only two Gram-positive species to grow: Staphylococcus and Micrococcaceae. Now we are down to two suspects. We know that according to Table 2, our unknown bacterium did grow on MSA but there weren’t any colored zones around the colonies. This means that our unknown bacterium is a non-fermenter. This was confusing at first but Superfarmer’s Weblog confirms it. On their website, they’ve confirmed that Micrococcus luteus (Micrococcaceae) do indeed grow on MSA and it is a non-fermenter thus backing up my believe that Micrococcus luteus is our unknown bacterium. But I also know that you’re saying “Staphylococcus can also grow on MSA too!” and I totally agree but as you can see under the blast result in the “Result” portion of this paper, none of the top blast result had Staphylococcus but they did have Micrococcus luteus which backs up my belief even more that Micrococcus luteus is our unknown