Fill-in the blanks & R-groups for each of the α-amino acid...

Question

Fill-in the blanks & R-groups for each of the α-amino acids from memory.

Illustration of amino acids with fill-in-the-blank prompts for memorization.

Accepted Answer

Hey guys. In this video we're going to utilize and compile all of the memory tools for memorizing the 20 alpha amino acids into one single video. And so it's gonna be a pretty long video, so feel free to fast forward to any portion that's going to help you guys out the most. Now for those of you that have already memorized the 20 alpha amino acids, then that is great news. And if you're short on time, then feel free to skip this entire video since all of the information is review from our previous lesson videos and there's no new information. But, if you're struggling to memorize these 20 alpha amino acids, even just a little bit, then this video is going to be super helpful for you guys, especially since the memory tools will not only help you in your current biochemistry course, but they will also help you moving forward as you transition into perhaps medical school or graduate school or really any professional field that might expect you to memorize these 20 alpha amino acids. Now guys, trust me on this one. I've tried looking and you won't find another video like this one outside of clutch prep that utilizes all of these memory tools to memorize these 20 alpha amino acids. So take advantage. Watch this video as many times as you need to in order to get a good grasp on these memory tools and to memorize these 20 alpha amino acids. Now that being said, you'll get the most value out of this video after you first attempted to fill out all of the blanks and the r groups on this page for the each amino acid, from memory yourself before you first watch this video. So, you can use this video to fill in the remaining blanks and the remaining r groups after you've first given it a try yourself. And so we're first gonna start off by remembering the mnemonics that help us, group these 20 alpha amino acids into 4 different groups. And so after we do that, then we're going to identify phonetic three letter codes in each group, phonetic one letter codes in each group, and then fill out the remaining amino acid codes. And then we'll fill in the R groups, utilizing memory tools for all of the amino acids in each group. Then at the very end, we're going to utilize memory tools to identify the essential amino acids. And so, we'll start off with our non polar amino acids which are our hydrophobic or water fearing amino acids. And you can think about my buddy Gavin, who goes by Gav, and so he recently hurt his leg and so he's not able to run. He has to limp around everywhere. And he's been afraid of water ever since he was 2 or 3 years old, so he's very hydrophobic. And so whenever he's sitting on the beach and a huge wave comes his way, he always gets up really quickly, grabs his crutches, and he limps away as fast as he can. And so you think about our mnemonic GAV LIMP, where each of these letters represents a one letter amino acid code for the 7 nonpolar amino acids. Now for the aromatic amino acids, you think about the aromatic benzene ring. And so you think about our fat, young whippersnappers. Now for the polar amino acids, you think about the North Pole. And of course, we know that Santa Claus is in the North Pole, so you think about Santa's team crafting new quilts every year for Christmas. And then for our charged amino acids, you think about our mnemonic, dragons eat knights riding horses. And so those are the 4 mnemonics that help us, remember the 4 groups that those amino acids fall into. And so going back up to our non polar hydrophobic amino acid group, we're going to identify any phonetic three letter codes, and the mnemonic that helps us memorize the 4 phonetic three letter codes is just asparagus or asparagine, chillin' on 3 tropical islands. And so recall that the 3 is only here to help us remember that this mnemonic is specific to the three letter amino acid codes. And so ASN is for asparagine, GLN is for glutamine, TRP is for tryptophan, and ILE is for isoleucine. And so what do you guys think? Looking at this non polar amino acid group, are there any amino acids that have a phonetic three letter code? Yes. That's right. So taking a look at isoleucine here, ILE, notice that it is part of our non polar group because the I here is for isoleucine. And so what we can do is we can put isoleucine's 3 letter code over here. Now notice that none of the other amino acids in this group have a phonetic three letter code. So that means that their phonetic their three letter code is gonna be super easy because it's literally just the first three letters of the amino acid itself. And so g is for glycine, so it's gonna be g l y. A is for alanine, a l a. V is for valine, v a l. L is for leucine, which is l e u. M is for methionine, m e t. And p is for proline, which is p r o. Now, moving on to our phonetic one letter codes, recall the mnemonic that helps us memorize those is just nerdy, Waldo, qualifies, and Fortnite. And so are there any, looking at this non polar amino acid group, what do you guys think? Are there any that have a one letter code of phonetic origin? No, that's right. So notice that none of these in the non polar amino acid group have a phonetic one letter code, which means that its one letter code is gonna be super easy because it's literally just the first letter of the amino acid itself or k for lysine. But lysine is not part of this group so it's literally just gonna be the first letter of the amino acid itself. So for glycine, it'll be g. For alanine, a. Valine, v. Leucine, l. Isoleucine, I. Methionine, m, and proline, p. Alright. So now we can move on to our next group, the aromatic amino acids. And so what do you guys think? Are there any of these aromatic amino acids that have a phonetic three letter code? Yes. That's right. So recall that tryptophan so if we go back up to our phonetic three letter code, recall that tryptophan does have a phonetic three letter code and tryptophan is the w in our mnemonic. And so what we can do is we can put tryptophan's 3 letter code over here. Now for the others, they do not have phonetic three letter code, so it's literally just gonna be the first three letters of the amino acid itself. So for phenylalanine, it'll be p h e, which is the f here. For tyrosine, it'll be t y r. Alright. So how about the phonetic one letter codes? Are there any phonetic one letter codes in this aromatic amino acid group? Yes. That's right. All 3 of them have phonetic, one letter amino acid codes. So the f here is going to be for phenylalanine, the y is for tyrosine, and the w is for tryptophan. And so all of those fall into our nerdy WQF mnemonic. Now, moving on to the polar amino acids down below, are there any that have a phonetic three letter code of origin? Yes. That's right. So take a look at asparagine and glutamine. And so asparagine and glutamine, if we go back up to our three letter code, so asparagine and glutamine are both part of the polar amino acid group. And so down below, we can go ahead and indicate that they have phonetic three letter codes. And so a spare gene is going to be, this one over here, and glutamine will be over here. So how about for phonetic one letter codes? Are there any in the polar amino acid group that have phonetic one letter codes? What do you guys think? That's right. So notice that, both asparagine and glutamine also have phonetic one letter codes, and so, we can go ahead and place those in here as well. And so that means that all of the other amino acids, for the three letter codes, it's literally just gonna be the first three letters of the amino acid itself. And so for serine, it's gonna be s e r. For threonine, it's gonna be t h r. For cysteine, it'll be c y s. And then for the one letter codes, because these are not a phonetic origin, it's literally just gonna be the first letter of the amino acid itself. So for serine, it'll be s, for threonine, it'll be t, and for cysteine, it'll be c. Alright. So pretty easy so far. Right? So now moving on to the charged amino acids, what do you guys think? Are there any of, the charged amino acids that have phonetic three letter codes? No. That's right. So none of these have phonetic three letter codes, which means that their three letter codes is literally just gonna be the first three letters of the amino acid itself. And so for aspartic acid or, aspartate, it'll be a s p. For glutamic acid, it'll be glu. For lysine, it's gonna be l y s. For arginine, it'll be a r g. And for histamine, it'll be h I s. Now, are there any of these that have a phonetic one letter code? What do you guys think? Well, that's right. So notice that aspartic acid has a one letter code, of phonetic origin, so we can put that in. So does glutamic acid, and, so does lysine and arginine. And so, lysines is k and arginines is r. And histidine is the only one that does not have a phonetic one letter code in the charged amino acid group. And so it's literally just gonna be the first letter of its, of the amino acid itself. And so now we filled in all of the abbreviations for all 20 of the alpha amino acids. So now what we're gonna do is go back up and we're going to fill in the r groups for each of these amino acids. Now recall that glycine's r group is so easy. It literally just glides right on through, and so that's because it's a hydrogen atom. It's the smallest, r group of them all and the easiest to remember. Now alanine, because a is the first letter of the alphabet and that's easy to remember, alanine's R group is also pretty easy to remember because it's literally just a methyl group or a CH three group. And so, just like alanine is or just like A is the first letter of the alphabet and it's the leader for all of the other letters of the alphabet, alanine pretty much acts like a leader amino acid for a lot of the amino acids, and we'll be able to see that moving forward in this video. Now, next what we have is valine, and already valine is going to be using alanine as it's, it's gonna be using alanine as a leader. So essentially what you're gonna see is these arrows that go back, show how these amino acid structures feed off of the ones that are neighboring. And so valine is literally just alanine with a v shape. So it's gonna be a CH 2 here or a CH, and it's gonna have a v shape, so 2 methyl groups coming off, and that is valine structure. Now, leucine, which is next, is literally just going to be a loose extension of valine. So leucine structure is feeding off of valine structure. And so, again, it's gonna be a loose extension of valine, so it's literally just gonna have a CH 2 and then it's gonna have a c h, and then it will have the v shape. And so by loose extension, we just mean that it has an extra c h 2 in here in comparison to this valine. Now, isoleucine, which is the next one, is really an isomer of Leucine. So it has the same exact chemical formula but it, arranged in a different format. And so isoleucine structure really branches off of valine structure. And so isoleucine is really just a lopsided valine. And so, by a lopsided valine, all we need to do is draw a valine, and then we need to make it lopsided. And so that is isoleucine structure. Now for methionine, its r group looks like an m. It's one letter code. And so literally, it goes down, it goes back up, and then it goes back down, and you can see that it's got this m looking shape to it. But because methionine has the meth, has the meth in it, so it stands for a methyl thiol, so it has a methyl group and a thiol group, we know that that has to go at the very end of the molecule. And so essentially what we're gonna have is the same m here, but at the very end there's going to be a sulfur atom and a, methyl group coming off of it. And so that is methionine structure, looks a little bit like an m. Now for proline structure, you can think that this p here really does look like a proline structure. So you can think the backbone of the p, just like the backbone of the amino acid, is going to be going across like this. And the loop of the p here is really like the r group of proline. So it's like a flipped p. And you can also think proline pentagon. And so, literally, what you'll see is that it's going to make a pentagon shape that loops back up. And so this pentagon is just made up of a bunch of, methylene groups or a bunch of c h two groups. So essentially, it's gonna have a c h two here. It'll have another c h two over here, another c h two here, and then it'll link back to the original nitrogen. And so notice that it has an n h two on its amino group rather than an NH 3 like all of the other amino acids, and again, that's because it has a cyclic r group. And so that is it for all of the non polar amino acids, and so we can move on to the aromatic amino acids. Now for the aromatic amino acids, we're starting off with f which is for phenylalanine. And phenylalanine is literally trying to tell you what its r group is. It's literally just alanine with a fetal group. And so if we go back up a little bit, we can see that alanine is a leader amino acid. So it's going to lead for the 1st amino acid that is part of the aromatic amino acid group. And so, alanine is a CH 3, so we we know that the number of hydrogens are gonna change. It's gonna end up being 2, and so it's gonna be alanine with a phenyl group or a branching benzene ring coming off of it. And so that is it, that is phenylalanine structure and that is it for phenylalanine. Now, tyrosine is feeding directly off of phenylalanine structure. So, essentially what we have here is that Tyrosine is phenylalanine with a hydroxyl group baby coming off the bottom. And again, the baby is going to be coming off of the bottom of the benzene ring, not the side or the top or anything crazy like that. It's gonna be coming off the bottom. And so all we need to do is draw phenylalanine exactly, so there is phenylalanine. And then for tyrosine, we need to draw a hydroxyl group baby coming off the bottom, And that is it for tyrosine structure. Now for tryptophan, it's really gonna try to trip trip you up because it's our group is pretty complicated, but we have good memory tools that's gonna help us remember this. And so tryptophan is literally just alanine with 2 joined rings branching off. The first is a 5 membered ring and the second is a benzene ring that's going to go below the structure. And because it goes below, we're going to draw that 6 membered ring last. So we can go ahead and draw an alanine, so it's gonna be CH, and we know that the number of hydrogens are gonna change it too. And then it's going to have a 5 membered ring coming off of it. So there's the 5 membered ring. And again, we're gonna draw the 6 membered ring, the benzene ring, last since it goes below the structure. So next, what we need to do is determine where this nitrogen atom goes. And so what can help us remember where the nitrogen atom goes is that, tryptophan trips on a tripod, and a tripod has 3 legs on it so that can help us remember that there's a 3 carbon start before you actually get to the nitrogen. And so that means that we here's 1 carbon, here's 2 carbons, here's 3 carbons, and our nitrogen can go right at this position over here. And so we can go ahead and get rid of these dots here and put our nitrogen at this position. And then, of course, what we're gonna do is draw in our benzene ring. Now our benzene ring has to go below. So we know that it can't go on this side. It can't be joined to the ring on this side because it would be above. It can't be joined to the ring on this side because it would be above. And, also, the benzene ring, does not include the nitrogen. So the nitrogen is not part of the benzene. And so that means that the benzene ring can't be joined on this side, and it can't be joined on this side. And this is the only side that the benzene ring can be joined to. So that means that here we can put our benzene ring. And, essentially, all we need to do is fill in the double bond, and the double bond does not touch the benzene ring or the nitrogen atom. So the only place that that double bond can go is, right at this position here. And so, of course, we gotta fill in our hydrogen atoms and that is it for tryptophan structure. And so now, we can move on to our next amino acids which are the polar amino acids. And, of course, the first amino acid that we have is serine. And, again, serine's going to be using alanine as a leader amino acid. And even though Santa and his team know that alcohol is a serious threat, they know that they can have it in moderation as they craft their new quilt. So by remembering that alcohol is a serious threat, that reminds us that both Serine and Threonine are the only 2 amino acids in this group that actually have alcohol groups. And so serine is literally just gonna be alanine with an alcohol group. So it's gonna have CH and we know the hydrogens are gonna change it too, and then it's gonna have an alcohol group coming off, so an o h. And that is it for serine structure. Now, three d structure is really branching right off of serine structure, and so, that's exactly what we're gonna see here. And so, what you'll see is that it's literally gonna have the carbon here and it's gonna have the Oh group. And so really, what you can think is that threonine has 3 parts on its central carbon here, and those three parts are a hydrogen atom, so it has a hydrogen atom over here, and it has a methyl group as well, and then it has the hydroxyl group. So that is it for threonine structure. Now, cysteine here, remember, is our crafting hammer and so Sistine spends a lot of time in the Sistine Chapel. And the Sistine Chapel is a church. And so when you think about the North Pole, you think about Santa Claus, you think about Christmas, and then you think about churches. And so Sistine spends time in the Sistine Chapel, this church, and whenever somebody makes a noise, cysteine is always just like shhh. And so cysteine is literally just alanine with a shhh group, an s h group. And so we can draw an alanine, so it's c h, we know the number of hydrogens are gonna change it to, and then it's gonna have an s h group, a sh group. And that is it for cysteine structure. Now for a spargene, we know that it has a one letter code of an n, and these parallel lines in the n here can remind us of a, of an amide group. Because we know that amide groups have double bonds, and so this, parallel lines in the nitri the n here can remind us of double bonds and the n reminds us of the nitrogen atom. And so we know that it's going to be literally, alanine with an amide group coming off of it. And so alanine is CH and we know the number hydrogens are going to change it to, And then it's going to have an amide group coming off, and so there is asparagine. Now for glutamine, because it has the glute in it, the glutes remind you of your butt section. And so glutes has the glute, so it's gonna have an extra butt section in comparison to asparagine, so it's feeding directly off of it. And so, what you'll notice is that, glutamine's structure is gonna be exactly the same as asparagine, but it's gonna have an extra c h two butt section. And so it'll have a c h 2, an extra CH 2, and then it'll have the amide group down here. And that is it for Glutamine. So now we're finally moving on to our final and 4th group here, the charged amino acids. And so, we know that there are 2 subgroups for the charged amino acids. We have, aspartic acid and glutamic acid, which are the negatively charged acidic amino acids. So over here, we can put, that these are the acidic amino acids. Actually, we'll put this in blue to color coordinate it. We'll say that these are the acidic amino acids. And then over here, that means that the positively charged ones are going to be the basic amino acids. And so we can start off with aspartic acid and, since aspartic acid is the first amino acid in this group, we know that it is going to essentially have a, it's going to use alanine as the leader amino acid. Acid. So aspartic acid is literally just alanine with a carboxylic acid, and that's what makes these, groups acidic anyways. And so aspartic acid is literally just alanine, so it'll be CH, and we know the hydrogens are gonna change it too, and it'll have a carboxylic acid branching off. And so that is aspartic acid right there. Now, for glutamic acid, again, it has the GLUT in it and the GLUT is the extra butt section. So it's gonna be branching its structure off right off of aspartic acid. And so it's gonna be exactly the same except it's gonna have an extra butt section or an extra c h 2. So it'll be c h 2, an extra c h 2, and then it'll have the, carboxylic acid group, and that is glutamic acid structure. So now moving on to lysine, recall that lysine is, acting like the knight in our mnemonic. And so, lysine's R group literally looks like a knight's sword. And so, we count up how many points lysine, lysine's one letter code has that you could try to poke somebody with, since you used knight's swords to try to poke people with. And so we know that there's, 4 pointy ends here, on lysine's r group, on lysine's one letter code. So that reminds us that there are 4 there's a 4 carbon start to lysine's r group. And so, essentially, it's gonna be a c h 2, another c h 2, another c h 2, and then a 4th c h 2. And then at the very end of this r group, there's going to be an amino group that is ionized and will have a positive charge on it. And that is it for lysine's r group. Now, in our previous lesson videos, we were skipping arginine and going to histidine first, and then after we filled out histidine, we would come back and complete arginine. So we're gonna do the same thing here. And so histidine, we know is acting like the horse in our mnemonic, and really histidine is just alanine with a 5 membered ring on it. And so, all we need to do is draw an alanine, so it's CH, and we know the hydrogens are going to change it too. And then it's going to have a 5 membered ring branching off of it. So it's gonna look like this. And so histidine's, R group really looks like a horse. So it's got these back legs here. It's got the front legs, and then we know that it has, 2 nitrogens. There's gonna be a nitrogen here that's acting like the neck of the horse, and then the second nitrogen we know is not being stepped on by the horse. So that means that it has to go at this position over here. And so we know that it's the neck of the horse here, the nitrogen at the neck of the horse, that is going to be protonated to give a positive charge here. And so essentially that is it for histidine structure. So now moving on to arginine, arginine has features of the knight's sword or lysine's R group, as well as features of histidine's R group, the horse. And so because it has features of the Night Sword, we count up how many pointy ends arginine's one letter code has that you could try to poke somebody with. And so there are 1, 2, 3 pointy ends that you could try to poke somebody with, so that reminds us that there's a 3 carbon start to arginine's r group. So it'll have a c h 2, a c h 2, and a third c h 2. And then this 3 carbon start here also reminds us that there's a triangular nitrogen structure or a nitrogen structure with, 3, nitrogens to it. And so the way that this nitrogen structure works, this triangular nitrogen structure works, is that there's a nitrogen, there's a carbon, and then there's another nitrogen, and then this carbon here is double bonded to another nitrogen. And so you can see here that we've got our triangular nitrogen nitrogen structure right there. And so, this first nitrogen here is going to have 1 hydrogen, this one here will have 2 And so, And so, essentially, you can see that it's got features of a knight's horse here because you can think of this n h two here as a person and the double bond as legs straddling a horse. So you can think here is our sideways horse and you can think that these double bonds, right here, these double bonds are like 2 legs, and, you can see that a person is up here, riding us a horse sideways, essentially. So it's a little bit of a stretch, but hopefully, that'll help you guys a little bit with memorizing its structure. And so that is essentially it guys. We've completed all of the r groups and the blanks up above from memory using all of our memory tools. So now what we're going to do is recall the mnemonics that help us memorize the essential amino acids, and recall that there are 2 mnemonics. The first one is, try, this, v I p mol. And so essentially, the essential amino acids in this mnemonic over here is just going to be, tryptophan here, threonine, histidine, valine, isoleucine, phenylalanine, methionine, remember the a here you want to ignore. L is for leucine and, this is for lysine. And so this mnemonic over here, if you if it works for you, then fantastic. But over here is a mnemonic that I came up with, and remember that it is I let, so I let, Martin Luther King, or MLK, trip his favorite his favorite video character. And so, essentially what we have here are isoleucine, threonine, methionine, leucine, Lysine, Tryptophan, Histidine, Phenylalanine, and Valine. And so up here in these blanks here, we can essentially put in these three letter codes. So we have isoleucine, we have threonine, methionine, Leucine, Lysine, Tryptophan, Histidine, phenylalanine, and valine. And these are the essential amino acids. So now we've completed this practice problem entirely and hopefully you guys can complete this video and, complete this page about 3 times on your own, and then you guys will have all of these memory tools down packed, and you'll be ready for the exam. So I'll see you guys in our next video.

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Fill-in the blanks & R-groups for each of the α-amino acids from memory.

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