June 17th - Making Nucleosomes

                This week I began the process of making nucleosomes. On Wednesday, we received a 500 mL supply of whole chicken blood, and I started the process of purifying 50 mL of it. Because the volume is “whole” chicken blood, it contains plasma, red blood cells, and white blood cells and platelets (see the image from the American Red Cross below). Birds are unique because their red blood cells contain nucleosomes, so the first step of the procedure was to isolate those cells. Such isolation was achieved by centrifuging the samples multiple times, and achieving a separation similar to the image below. The supernatant was the plasma, which was discarded, and the white-film on top of the red blood cells was also discarded.

                The next step in the procedure was to lyse the red blood cells, thus releasing the nuclei. Again, the samples were spun in the centrifuge and after successive spins, we were left with a clean, white precipitate. Over the next few days, we will work towards isolating just the nucleosomes from the nuclei.