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3. Amino Acids

Nonpolar Amino Acids


Memorizing Nonpolar Amino Acids

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in this video, we're gonna talk about our first group of amino acids, the non polar amino acids. So the non polar amino acids all contain are groups that are largely hydrophobic and again recall that hydrophobic just means that their water fearing and that they do not mix well with water. And so the reason that all of these are groups air hydrophobic is because they all lack terminal electro negative atoms. And by that what we mean our electro negative atoms that are at the very ends of a molecule and are able to easily interact with the water so they lack those. And that's why they're hydrophobic. And it turns out that there are actually seven amino acids that air grouped as non polar amino acids. And these are glazing Alan unveiling. Losing is a losing meth inning and pro lean. And so you might be wondering, Jason, how am I supposed to memorize? All these amino acids are non polar, and we'll get to that very shortly once we get to our example in our pneumonic, which is gonna help us memorize these amino acids as being non polar. But before we get to the pneumonic I wanna remind you guys of two important things. The first is that hydrocarbon structures or structures that Onley have hydrogen and carbons are very non polar and hydrophobic. So the mawr hydrocarbons that there are in our group, the mawr non polar and the more hydrophobic that our group will be. So that's something to keep in mind as we go through are non polar amino acids. And the second thing I want to remind you guys up is that the groupings of these amino acids is actually relative, and they can vary from textbook to textbook. And so although your textbook or your Professor Mike Group other amino acids into the non polar group, we've specifically decided to group them elsewhere in a different group just to maximize the effectiveness of remembering not only the groupings of the amino acids but also for remembering the structures of the are groups themselves and will be able to see how that works as we go through our examples in our lesson videos. So now let's move on to our example down below of all the non polar amino acids, all seven and so first, we're going to start with this pneumonic. And so the pneumonic for the non polar amino acid is is just Gavle limp and again recall that the non polar amino acids are all largely hydrophobic or water fearing. And so here's the story behind Gavle limp. I've got this friend. His name is Gavin, but really he just goes by Gap. That's his nickname. Gaffe. So everybody calls him jab. And so Gava actually broke his ankle a couple of weeks ago. He was trying to do a back flip off a trampoline or something crazy whatever. Anyways, he broke his leg and he can't run anymore. So now gaffe can Onley limp everywhere. He's got a cast on his leg, and he's always got these crutches and he's just limping around. And gaffe has always been super afraid of water ever since he was two years old. So Gabby's super afraid of water in the super hydrophobic and whenever Gavin's just chilling on the beach lately, uh, on a big wave starts to come. You'll see Gabby get up real quick, and he's got grabs his crutches and he tries toe go assed fast as he can, But he can't run. He can Onley limp And so you can see Gavin right here, limping away on his crutches, away from the water because he's hydrophobic. So if you can remember Gavle limp, you can remember that Gavle limp away from the water. And that's why those of the hydrophobic non polar amino acids. So hopefully that will help you guys remember gavlin, the non polar amino acids. So now let's go in and talk about each of the non polar amino acids one by one. So the first on our list is G and G. Remember is the one letter code for glistening and so in these blanks. What we're gonna do is we're gonna put the three letter code and the first blank and the one letter code in the second blank and so glistens. Three letter code is actually G l Y cli scene, and it's one letter code is G, and it turns out that glistens. Our group is one of the easiest to remember. It's literally just a single hydrogen atom, and so it actually has the smallest our group, and glistens just so easy that it's our group literally just glides right on through, figuratively, because it's just so easy but also literally because it's our group is so small it can just glide into like, pretty much any place at once to without encountering ah, lot of hysteric resistance. It could go into a little small spaces that other are groups can't fit into. So glistens. Our group is the smallest, and it's one of the easiest to remember. It's just a single hydrogen. All right, so the next on our list is Alunan or a and so a uh, The three letter code for Alan in is just a l A. And it's one letter code is a and, just like a is the first letter of the alphabet. So just like a is the first letter of the alphabet. A and Alan nine are both really easy to remember, because the our group of Allah nine is just a simple metal group. It's just a simple metal group, so we can go ahead and put in our metal group here. So it's just a ch three methyl group, and also just like a is the first letter of the alphabet. A. The letter A is the leader for all of the other letters in the alphabet and in a similar way. Alunan is also a leader for all of the other Kyrillos amino acids that are in not only this group, but also in the other groups. And remember that glazing over here the one that we already talked about is the Onley amino acid that is not Cairo. Glazing is a Cairo. So that's one of our, um, learning objectives from our amino acid configuration lesson. All right, so now that we've no Alan, I mean, let's now talk about veiling and again, like we just said, uh, Alan in is a leader and so veiling kind of copies off of Allan E. And so veiling, which is the next one in our list here. Valeant's three letter code is V A L. And it's one letter code is V. And so what you'll see is that will first draw Allan e so ch on the hydrogen zehr gonna change. So we'll we'll leave them, uh, blank for now. How many hydrogen? And so you can see that it looks really like Alan in right now. But that veiling actually literally looks like a V. So veiling is literally just a winning. But it looks like a V. And so what we could do is put a V here. And now we've got a winning. So what we've got is ch here, and we've got to methyl groups at the ends of these, uh, carbon chains here. So this is the structure of veiling. It's Alan. I mean, that looks like a V shape. So next on our So now we're done with gaffe. So we finished completely with Gabby, and now we're moving on to the limp, which is down here on the bottom. So the l here represents. Loosen the one letter symbol for losing and loosens. Three letter symbol Is Elie you? The first three letters, It's one letter is L and so loosen turns out to be just a loose loosen is a loose extension of veiling and veiling. Remember, is just a V shaped Allan E. And so loosen because it's a loose extension of veiling. What that means is it's going to have an extra methylene groups, so it's gonna have a ch two. It's gonna have another ch, and then it's going to have its three. It's a V shaped veiling, so you can see that it's literally just veiling with an extra CH two shown here. And so that's why it's a little bit more loose. It's got a little bit more flexibility in the chain because it's a little bit longer. Now. The next amino acid in our list is I and I stands for Is a losing and I solutions. Three letter code is I l E. And it's one letter code is I? And it turns out that is a losing is actually what's known as an ice Um er, and that's why it says isso in front of it to remind us that it's actually an ice Um er, and it's an ice, um er of losing, which comes right before it. And so what you'll see is remember that ice swimmers have the same exact chemical? Uh, Adams. They have the same exact number of atoms and types of atoms, but they differ in the arrangement of those atoms, and so the arrangement of is a losing. It's just that literally a lopsided veiling. So it's a lopsided veiling, and so what we can do is we can first draw availing, which is just gonna be ah ch with a V V shaped ch here and then we can make it lopsided. And by making it lopsided, we could just add a neck stra methyl group here. And so that's the structure of is a losing. It's a lopsided, uh, veiling and an ice um er of losing now for our next, uh, amino acid. What we have is m so we're getting close to finishing the limp and M stand is one letter symbol for meth. I Inning and Matthias means three letter code is M E T. And it's one letter code is just m. And it turns out that Mathias means our group literally kind of looks a little bit like an m itself. It literally looks like a nap. And so what we can do is that we can go ahead and fill in for this. Our group, it literally goes down, back up, and then it goes down again. And so you can see it kind of looks like this m Here. It looks like it goes up, down, up, down. So it looks a little bit like an M here, a sideways M. And so the the other thing that you need to remember about meth, I ning is that it has a meth full group. But it also has ah thigh all group. And if you can remember back from our functional groups that a methyl group is a ch three and a Thile group is one that has a sulfur atom. And so for the positioning of this method Thile, it actually has to go at this position here. So we have to essentially remove this uh, portion of the M here. So we've got to remove this portion of the M. So let's redo RM so it goes up, down and then at this position here, what we could do is fill in our sulfur and then complete arm Ethel Group. So we still got our M shape in here where it goes up, down, up, down kind of like that. So it looks like an end. But we've got also our methyl file, which is this group, uh, this shaded group group. That doesn't look good. It looks like this group right here is our metal file. So that's, um, a thiamine right there. And then lastly, what we have is pro lean and so with pro lean, that is the last letter of our group here. It's just the P here. And so with Pro Lean, it's three letter code is P R O. And it's one letter code is a peak. And it turns out that pro leans. Our group literally looks like the loop of API itself. So whenever you draw a P, you have to draw loop, and that loop kind of comes out, and then it comes back to the backbone. And so the backbone of the, uh, amino acid is going side to side like this, and you can see that the P part. It kind of loops up like this so you can see that pro liens are group literally looks like loop of Apia flipped P. And so that's why we have that in here. So then, uh, it looks like the loop of a flip pre. But you can also think of pro lean whenever you say pro lean. You can think of pro lean Pentagon, since they both start with P. And what you'll see is that the pro leans. Our group literally looks like a Pentagon where you have one side here, one side going out, then it comes back. Here goes over here, and then it connects back to the end. So pro leans. Our group is interesting because it's the Onley, one that actually loops back and connects to the amino group. It's the Onley, one out of all of them that has a cyclic, our group or one that does a cycle and goes from one point and comes back and connects to a the same similar point. So now let's go ahead and fill in for, uh, pro leans our group. And so what we can do is we'll put in a ch two here. It's all methylene so methylene zehr ch two and then it connects again over here as a CH two. Then it connects. Here is a CH two, and then it finally connects back to the nitrogen and noticed that pro leans nitrogen has one less hydrogen than all of the other hydrogen on the other nitrogen. So it has a NH two rather than an NH three, and this is the Onley amino acid that does that. So that has to do with the fact that pro leans our group is cyclic and connects back to the nitrogen. And so this concludes our lesson on the non polar amino acids, and as you get more and more practice, you'll be able Thio, get the hang of these different memory tools and be able to memorize these structures a little bit better. So we're gonna get the to the practice and I'll see you guys in those videos.

Draw in the R-groups from memory for each of the nonpolar amino acids.

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Fill-in the missing R-groups for the following tripeptide: L-A-M. 

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