unknown on streak plate

My group found the unknown to be S. Aureas. Reasons would be that it could eat the mannitol and we discovered that by noticing that the agar on the MSA turned yellow. It can also grow in high salt conditions because it formented on the MSA. It didn't grow on the EMB agar like E. Coli did so it is gram + because gram+ can not grow on an EMB plate. Therefore, the unknown is S. Aureas.

My group had determine taht the unknown is also S. Aureas. Same reason as in Marisa group.

My lab group thought that our unknown had to be staphylococci (or s. aureus) because by doing our streak plates/Kirby Bauer tests, be found out that the unknown was gram positive. We determined this because it did not grow on the EMB plate, but it did grow on the MSA plate. This meant that not only was it gram positive, but also that it could live in high salt conditions (above 75%). It was also yellow, which meant that it can ferment Mannitol. Since our unknown was in the yellow area of the DNAse plate instead of blue, that meant that our unknown was able to eat DNA. With all of our evidence, our unknown mostly resembled the S. aureus and once under a microscope, it was staphylococci because it was purple (gram positive) and in large clusters that looked like grapes.

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