Jessica Steigerwald's blog

Week seven of my internship included a lot of reading papers and waiting for bacteria to grow.  This week and next, we are working on conjugating the plasmid containing the delta DNA fragment (the one without the gene of interest) into Teredinibacter turnerae.  However, this step requires aligning the growth of the E. coli and the T.

Week six of my internship was an exciting if rater uneventful week.  Monday was not too busy.  I transformed the Δ1990 DNA fragment into the E. coli competent cells that we made last week.  These then got plated onto an LB/agar plate containing Kanamycin.  We also sent in to be sequenced ten DNA fragment samples for the ΔtnbA gene, and I re-streaked ten new ΔtnbA colonies to use in case the sequencing results come back with mutations in all of the fragments.  Because we did not have a lot of work, I had some time to myself to work and read journal articles.

This week was a little bit slower for the others while we waited to hear back about the sequencing results concerning the DNA fragments we constructed in the previous few weeks. Monday morning we sent out all of the samples from last week to be sequenced. Afterward I prepared an LB/agar solution and put it in the autoclave. Then I spent some time finishing my blog for last week and working on my PowerPoint slide for the midterm presentations this Thursday. After lunch, I took the LB/agar mixture out of the autoclave and put it in the 55^oC water bath.

This week I finished up the first stage of my project, preparing the DNA fragments that contain only the upstream and downstream segments from the genes of interest.  The next step, which I started this week is to send the fragments in for sequencing to make sure there are no unintended mutations in these regions (obviously the gene of interest will be absent). 

This week was really exciting for me because a lot of the work that we had been doing up until this point began to make sense.  On Tuesday, Hiroaki sent out the first gene fragment for sequencing and on Wednesday I got to start my first solo reaction process. 

This Monday we started two more PCR reactions.  Hiroaki did one of them to remind me of the steps, and I did the other.  The new primer that we needed came in over the weekend, so the first step was to prepare the primer with autoclaved water.  Then we diluted a portion of the primer to a walking solution and used that to prepare the PCR solution.  PCR takes around two and a half hours, so after we started the reaction we took a lunch break.  In the afternoon, we started the second PCR reaction which will run overnight.  Then Hiroaki showed me how to inoculate

I am an undergraduate intern at OHSU’s Institute of Environmental Health (IEH).  This summer I will be working with Hiroaki Naka in Margo Haygood’s lab.