January 21, 2005
My first DNA electrophoresis
I am really, really enjoying my biology class, a concentrated term of cell & molecular biology. Students in this program spend about four times as much time in lab, learning industrially useful techniques, as do students in comparable programs in the University of California system. In the last three weeks, I've had hands-on time doing protein electrophoresis, conjugation (bacterial DNA transfer), and DNA electrophoresis. Here's an image of our team's first DNA gel:
The DNA is from purified coliphage Lambda virus, 48,502 Kb (kilobases) in length. Lane 1 is pure, uncut DNA. Lane 2 is DNA restricted (cut) by Eco RI enzyme, Lane 3 restricted by Hind III, and Lane 4 by both (the restriction sites are different, resulting in more, smaller DNA fragments.)
Lanes 5 through 7 are subsamples taken from 2 through 4, subjected slowly and thoroughly to the action of the enzyme DNA ligase, resulting in outrageously long, randomly recombinant strands.
The gel is purified agarose treated with ethidium bromide. The image above is a high-contrast Polaroid of the gel UV-transilluminated to fluoresce in the visible spectrum (reddish orange, here shown in black and white).
This stuff is outrageously fun.
Posted by Russell Whitaker at January 21, 2005 12:54 PM | TrackBack