Lab Report Bacteria

For this project, I am required to document the many activities to best determine what type of bacteria my unknown could possibly be. The first activity involved straining the bacteria and determining whether or not it was a Gram positive or negative. Straining can be quite difficult because there can be possibly that under-colorizing or over-colorizing can occur. Luckily, for myself neither of these outcomes occurred. Once I put the stains on the slide to create a gram strain, I put the stain under the microscope. I noticed that the majority of cells were purple. I knew right away that my bacteria must be a Gram positive. The cell shape was circular, which help me determine that the cellular morphology was coccus and the cell arrangement was in clusters. …show more content…
I created a streak plate using a nutrient agar medium. The nutrient agar was placed in a 37 degree Celsius for two days. I noticed that after two days, that colonies started to form. Each colony was circular in shape and very shiny. The surface texture was very smooth, but the elevation was very flat. The pigment was yellow however, I did not really consider this a very unique feature since all of my group members streak plate were all yellow. Also, my colonies did not touch each other and my bacteria smelled extremely bad. I can compare the smell to dog poop. Although, I knew my bacteria was a gram positive, I still did not know what type of genus or species. I had to run a series of tests to eliminate possible choices. Based on my cell shape I knew that my bacteria genus could either be Staphylococcus or Micrococcus. This was due to my cell shape and arrangement. I did a couple of test, however the one that best help me determine which species of my bacteria was Phenol Red Broth test and acid from mannitol