Today was another exciting day in the lab! Because the PCR reaction and the UV test was positive, Jessie was able to continue on with the ligation reaction. In science terms a ligation refers to the joining of two DNA fragments through the formation of a phosphodiester bond. The ligase is an enzyme that catalyzes this reaction. In this experiment the two DNA fragments were the digested vector and the Digested DNA insert – they were catalyzed and joined together by the T4 ligase. After a couple of calculations, which I will list below, it was found that the master mix for the DNA vector that would contain this reaction needed 2 microliters of the buffer, 1 microliter of the ligase, 2.4 microliters of DNA, and 13.6 microliters of water. On the other hand the master mix for the digested DNA insert need about 1.6 microliters of the DNA, 2 microliter of buffer, 1 microliters of ligase, and 14.4 microliters of water. 
Each piece of DNA needed to be placed in a buffer in order to ensure they do not die out and are sustained in proper conditions. After each of the master mixes were created and the ligation reaction was initiated, Jessi decided to show me another crucial part of a scientists life: cleaning! Because Jessi had not cleaned her glassware for a couple of days now, she decided that it was about due time to do so today. The procedure for cleaning glassware in the lab is similar to how we clean our equipment at school. First, like most would do at home, she poured a soap mixture into each dirty beaker, then she poured acetone, and finally rinsed each glass with water.
After all the glasses were washed, it was time to prepare some base solutions. These types of solutions are used every day in the lab and it is important to keep a constant supply. The optimal pH for the base solution was about 7.5. To gain the right pH, small concentrations of HCL and NaOH were poured to achieve the desired pH. To achieve this result, Jessie used a special pH meter donated by Dr. Lindsey’s previous boss. Overall, combined with the ligation and a new found appreciation for cleaning in the laboratory, this day was filled with so much fun and action!
