Hey, guys. So here we're going to quickly revisit our map of the lesson on membrane transport, and we know that we're currently exploring the active transport branch more specifically, the primary active transport branch. And we've talked about the five types of 80 p aces, including two very specific types of P type 80 pieces, which are the sodium, potassium pump and the circa pump. And so now in our next video, we're going to talk even more details about the ABC transporters, one of the five types of 80 p aces. And so I'll see you guys in that video.

in this video, we're going to talk a little bit more details about one off the five types of 80 p aces, the ABC transporters. And so really, the main take away of this video is that ABC transporters can provide multi drug resistance. And so the ABC part of ABC Transporters stands for a teepee binding cassette, ABC. And so the A T P binding cassette transporters or ABC transporters are really just integral membrane proteins with at least one ABC structural motif, and so recall that motifs are just a combination or a pattern of secondary structures and proteins. And again, because ABC transporters are a type of 80 p ace, they are a form of primary active transport. So it's no surprise that these guys pump substances across the membrane against their concentration ingredient from areas of low concentration to areas of high concentration. Now, another defining features of these ABC transporters are the structural elements that they contain. And so all ABC transporters actually share two common structural elements. The first are that they all contain too trans membrane domains or to T. M. D. S for short. And of course, as their name implies, these air trans membrane, so they spanned the membrane. And of course, that's going to help create this poor that allows them Ah, poor through the membrane that allows them to transport molecules across the membrane. Now, the second common structural element that all ABC transporters have is that they all have to saido Solich nucleotide binding domains or to N b. D s for short. And so these nucleotide binding domains will bind and hydrolyzed eight eep which recall a teepee, is a nucleotide. And so within these nucleotide binding domains, that's where you could find the 80 p binding cassette this specific structural motif. So if we take a look at our image down below notice, we're showing you an ABC transporter and embedded within this plasma membrane right here you can see the structure of this ABC transporter. Notice that spanning the membrane, there are these two trans membrane domains here that we have highlighted here in pink and then on the side of Solich side of the cell. We have these two nucleotide binding domains or these two n b. D. S. Right here. Of course, the nucleotide binding domains can bind and hydrolyzed 80 p as we see here, and that's exactly what we mentioned and described up above the to T. M. D S and the two and BDs. Now it's also important to note that some ABC transporters are called multi drug Resistance, or M D, our transporters for short. And that's because these will particularly be responsible for resistance to multiple drugs. And so in bacteria, NDR transporters will actually confer antibiotic resistance. And in humans there's a protein called P glycoprotein, or P E G P, which is an M d R transporter that removes anti cancer drugs from tumor cells. And so, essentially, what we're seeing here is that M. D. R s are of great importance to humans because M. DRS can confer antibiotic resistance in bacteria, which can create a problem, a health problem for humans. And so that's why ah lot of research goes into MDR transporters, uh, to see how we can work around the NBR transporters, that air providing antibiotic resistance to some bacteria that might be causing humans health problems and also in humans. It's also a new area of high research as well, because again, P glycoprotein here can remove anti cancer drugs and tumor cells. And so again, that can be very problematic. And it's an area that is very highly researched. And so what you'll notice here is we have this tiny little stethoscope over here on the left, and this is a symbol that we're going to use moving forward in our course to represent something that you might want to pay a little bit more. You know, pay close attention to it. Because if you're going on into medical school or some kind of other medical profession, like maybe pharmacy or something like that, wherever we have this symbol, this is a place where you might want to hone in and keep this idea in mind in case you encounter this idea again. Because if you're if you are going on into medical school or again some other kind of medical profession, this is an idea here that you'll probably revisit. And so if we take a look at our image down below, notice that we're showing you these red lines right here, uh, that are taking toxins and drugs and pumping them to the outside of the cell. And ABC transporters or MDR transporters can take toxins or drugs that are embedded within the plasma membrane and remove them. Pump them to the outside of the cell, and they can also take drugs that are in the cytoplasm and toxins that are in the cytoplasm and remove them and pump them to the outside of the cell against their concentration. Greedy int, while utilizing and hide relies ing a t p. And so this year concludes our lesson on ABC transporters, and as we move forward in our course, will be able to get some practice applying these concepts so I'll see you guys in our next video.