Our bacteria 'L' did infact thrive in the GasPak from last week. This means 'L' can grow in both aerobic & anaerobic conditions. This means our hypothesis from earlier was correct and our bacteria is facultative (it can grow in the presence & absence of oxygen). The Thioglycollate Broth also showed the same result: that 'L' is facultative. 'L' grew throughout the broth: present equally in both the top, red layer (where oxygen is present) and in the bottom yellow layer (where oxygen is not present).
Once we determined the oxygen requirements, we did several tests to figure out what 'L' ate. We took three nutrient agar plates each with a different nutrient. One contained starch, another had casein (a milk protein), and the thrid contained triglycerides (lipids). Using the aseptic technique & a inoculating loop, we spread bacteria 'L' onto all three plates and incubated them at 25 degree Celcius overnight.
We took the three out and examined the results. We had to cover the Starch agar plate with Gram's Iodine for 1 minute to see if the enzyme Amylase was present in our Bacteria. If it was a halo would appear around our bacteria streak. The casein plate was to see if the enzyme Casein Protease was present in our Bacteria. As shown by the halo around the bacteria, Bacteria 'L' does indeed contain Casein Protease! The triglyceride plate was to see if the enzyme Lipase was present in our bacteria. The dark blue color in our sample proves that Bacteria 'L' does eat triglycerides and contains Lipases.
Starch Agar with Gram's Iodine (negitive test)
Casein Agar (positive test)
Triglyceride Agar (positive test)
An upclose look at the halo atop Bacteria 'L'
Peace,
Annie B
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