Week 1

Since this was my first week back, most of this week was spent making new media and materials (Tris buffer, LBS, plates, purifying ethanol, etc.) so I didn’t have a lot of time left to work on my actual experiments, especially since my first run was unsuccessful. Towards the middle of the week, I began my experiments on the eight strains of V. fischeri that had been found to be resistant to ethanol levels between 4.0% and 4.9%. Since I am continuing the research done by a previous student, the strains were already identified to be able to survive at 4% ethanol but not at 5% so for these experiments I needed to grow the bacteria in a 24 hour culture in 0% ethanol LBS, then grow them in a 3 hour subculture in 0% ethanol LBS, then grow them for 24 hours again in ten different sets of media, from 4.0% to 4.9%, going up in increments of 0.1%. Unfortunately, both times I attempted this experiment this week, it was not successful, since the bacteria were not able to grow at the end of the 3 hour subculture and therefore could not be tested at each of the ethanol levels. This suggests that there was a problem with either the test tubes or the media itself. Since there have been problems in the past with small residues of antibacterial soap being left over in the tubes and making its way into the media, I decided to try again with new LBS media, in new tubes, so hopefully with these new tubes and the new media, I’ll have more success growing these strains next week.