We usually think of enzymes as being most active at around 37°C, yet in PCR the DNA polymerase is subjected to multiple exposures of relatively high temperatures and seems to function appropriately at 65–75°C. What is special about the DNA polymerase typically used in PCR?

Video transcript

Hello, everyone and welcome to today's video. So D N A polymer rise used in PCR is obtained from which of the following species. Well, before we jump into this problem, I want to remind you of something that we have gone over here in the curse will remember that PCR is going to subject the D N A strands to very high temperatures in order to separate them and then be able to replicate them. In order for PCR to be able to do this, we need a DNA polymerase molecule or protein that is thermal stable so that it does not the nature once we separate the strands, once we raise the temperature, so it has to come from an organism that is adapt at being at these very high temperatures. Now that we know this, let's go over each of the answer choices so that we may solve the problem. Let's begin by answer choice. We have Homo sapiens, which is going to be humans, what humans are not able to live a very high temperature. So we're going to cancel this out. Then we have the coal or remember that this is a bacterium that lives in the human gut because of this, we're going to cancel it out as well as this is not an environment of very high temperatures. If they were exposed to very high temperatures, that would die. Same thing happens with Joseph Milano Gaster, remember that this is a fly. So there are not very adept at being in very high temperatures. So we're going to cancel this as well. Now we have a thermos aquatica. if we see this name here, thermos, this is an organism that is going to be adapted to living in environments with a very high temperature. Because of this, it contains DNA polymerase is that are able to sustain the high temperatures coming from PCR. So we extract the DNA polymerase, we can use it in order to replicate the strength of that were being used in PCR. So answer choice B Thurman's Aquatica is going to be the correct answers to our question. I really hope this helped you and I hope to see you on the next one.