Summer Week 8

For the first time in my life I extracted DNA! Naturally, I started with one of the most notoriously difficult organisms to extract DNA from- fungi. Fungi are similar to plants in that their structure and support comes from rigid cell walls. However, in fungi the macro-molecule that the cell wall is made of is usually chitin instead of cellulose.

These macro-molecules must be broken down to extract any DNA, which is difficult because of how tough they are. Broadly, there are two ways to break down the cell walls; chemical or mechanical. Chemical degradation of the cell walls would be things like adding enzymes whereas mechanical is more grinding of samples or vortexing with glass beads to shred the walls. The method I used did a little of both.

To make grinding easier and more productive I flash froze mycelium samples in a bath of super cooled isopropyl alcohol. This makes the cytoplasm freeze and the walls brittle so grinding with a pestle is easier. After that I used an E.Z.N.A. Fungal DNA extraction kit that was full of buffers to further degrade the cell walls. I ran a gel on my resulting DNA, popped it in the UV viewer, and this is what I got: