Positive or Negative ???

When coming into lab today Courtney and I made a gram stain on each of our bacterias, the unknown and the dollar bill. The unknown turned out to be gram negative. We know this because it did not hold the crystal violet stain and took the safranin. This tells us that it has a thiner cell wall. The dollar bill bacteria had the same results as the unknown, it was also gram negative for the same reasons. The gram stain showed that our bacteria aren't streptobacillis but actually just single bacilli that were together or laying next to each other.

dollar bill

unknown

Just Keep Swimming, Swimming, Swimming...

On September 23rd, I (Courtney) went into lab on a break from work and tried to make another hanging drop slide. I had no luck and my break was almost up when I went to make another slide. When Hannah came into work (we work in the same department at Franciscan University) we went to try again. Fortunately, Dr. Pathakamuri was able to help us make the slide and look at it through a better microscope. The motility test was right! Our bacteria were swimming everywhere! We even got a video of it..

Do We Have Lazy Bacteria?

On September 22nd Hannah and I went into lab to check on all of the tests that we prepared the last class. Our streak plate showed a lot of growth in sort of round, flower shapes as Hannah described them. The motility tests showed that our unknown bacteria is motile or has the ability to move because there was a "cloud" of bacterial growth around the area where we stuck the needle. Meanwhile, the bacteria from the dollar bill does not move shown by no "cloud" or growth. Because our unknown is motile, we needed to make a hanging drop slide so we can actually see them swim. This is what the broth was for. What we didn't know was that our broth didn't grow enough bacteria to even do a hanging drop let alone see any bacteria. So we tried and failed somewhere around five or six times. Even Dr. Pathakamuri tried and he couldn't see them. Hannah and I joked about having lazy bacteria while our professor searched for what our unknown sample was and to see if it was truly motile. We ended the day with making a new broth that needed to be checked the next day.

New Tests

On September 20th we started to work more on figuring out what our unknown bacteria is. Hannah and I inoculated broth for both our unknown and the bacteria from the dollar bill. We also made a streak plate from one of the unknown slants and made two more simple stains that showed our bacteria is streptobacillus, or chains of rod shapes. Hannah and I also got to each inoculate a motility medium with unknown sample B and the bacteria from the dollar.

More Microscopes..

On September 15th we stained a couple slides of our dollar bill and unknown bacteria to look at again. They showed that our unknown sample B bacteria have the ability to form spores. We also looked at each of the slants we made. This lab time was more practice with staining techniques and using microscopes.

We Have Bacteria!

Again on September 13th we waited in line to get to the incubator, talking about what happened last time and seeing what our classmates are pulling out. Our spirits picked up after we saw our streak plate. That one little colony spread to cover almost the whole plate. Now we were able to check the colony characteristics and look at our plate under a microscope. This was the day we also got our unknowns. Hannah and I were given Sample B and all we knew about it was that everything made from it had to be placed in the 30 degree incubator. From our sample tube we streaked two slants. We also learned how to stain bacteria with a simple stain technique. Hannah and I were excited to use our dish full of bacteria from the dollar bill. It showed diplococci or small circles in pairs of two. Needless to say, we were pretty pumped for this lab.

Honestly Depressed...

In lab on September 8th, Hannah and I came into lab excited to see if there was any growth. After being told what was needed to be done (checking for growth, looking at the bacteria through a microscope, and characterizing the colonies) we waited in line at the incubator. We were slightly let down by what we saw. At first we thought there was nothing. But, in the corner, there was one single, lonely colony. So a dollar bill either isn't as dirty as everyone thinks or Hannah had a really clean one. We took the lone colony and made a streak plate with it. Let's hope more grows this time.