![pGLO contamination [CC-BY-SA-3.0 Steve Cook]](https://www.polypompholyx.com/wp-content/uploads/2013/02/pGLO_contamination_fun-300x224.jpg)
Yesterday’s first-year biology practical involved forcing the laboratory work-horse bacterium Escherichia coli to take up a circular piece of DNA called pGLO. pGLO contains a few genes, but the most interesting of these DNA sequences encodes a protein from a jellyfish. This protein fluoresces green under UV light, and goes by the thoroughly unimaginative name of green fluorescent …