One donor requested that I talk a little bit about polymerase chain reaction, or PCR.

PCR is now a super common laboratory technique for people doing any sort of molecular biology. It’s a way of amplifying a specific section of DNA so it’s present in millions of copies. This is really important if you want to, for example, sequence a specific gene. You want that gene to be present in such high quantity compared to the rest of the genome so nothing else is sequenced.

As for how it works…I’m not sure if I’m able to explain that in a coherent way right now, so here’s a handy dandy video!

Most PCR uses a specific type of DNA polymerase known as Taq. Taq is an enzyme that was originally isolated from Thermus aquaticus, a thermophillic bacteria that lives in hot springs and hydrothermal vents. Taq is special because it can withstand high temperatures without losing its function. Since PCR requires DNA polymerase to be functional at higher temperatures, this makes Taq super important. The one downside to Taq is that it’s not very good at proofreading, which makes it error prone. Thankfully DNA polymerase has been isolated from other thermophillic species. Pfu is an example of a thermophillic DNA polymerase with proofreading ability.

This is post 45 of 49 of Blogathon. Donate to the Secular Student Alliance here.