A couple of days ago, my colleague Mike sent me a link to the GenomeWeb Daily News report on the Draft Genome of a Bee Parasite. I got all excited when I read that the team of scientists used pyrosequencing to determine the eight million bases. I started imagining a cascade of fireworks in the fume hood. This important research provides insights into how genes contribute to the parasite’s virulence. Scientists believe this parasite plays a role in the bigger problem of colony collapse disorder. Mike sent me this article as he knew that I had an interest in honey bee genomics and blogged it in the past.

In relationship to the honey bee, Nosema ceranae is a microsporidian fungus that is an obligate parasite. This fungus first attributed to an Asian honey bee has recently become associated with European honey bees and is now widespread in Europe and North America. While much more analysis is still to come, genomic studies allow comparison of the parasitic fungi with free living fungi. Interestingly, the parasitic genome contains fewer genes involved in transport and chemical response than free-living fungi, but more genes involved in growth-related processes. It will be interesting to see future developments in this area.

Getting back to my excitement over pyrosequencing, well it turned out I had let my imagination run amok with the name. Doing a little fact checking, I realized that the naming of the technique comes from the fact that it involves sequencing by synthesis of a complimentary DNA strand. Incorporation of the nucleotides into the new DNA releases pyrophosphates, the anion described by this formula, P2O74−. Historically, this complex ion and others with the prefix pyro were discovered using heat to remove water. A mini-fireworks is involved in pyrosequencing however, and that comes from the chemiluminescent signal produced by an enzyme which detects addition of a new base to the sequence. I found a cool little video on YouTube illustrating the pyrosequencing technique.