Hey everyone. So in this video, we're going to take a look at our acidic and basic amino acids. Let's first start out with our acidic amino acids. They take the form of aspartic acid and glutamic acid. Now we know that with amino acids, we have three-letter codes, as well as one-letter codes. Three-letter codes are pretty easy because for the majority of the amino acids, they're just the first three letters of the amino acid's particular name. In this case, for acidic and basic amino acids, that's going to fit the description for the three-letter code. Here, aspartic acid, ASP, ASP. Glutamic acid, GLU, GLU. Now, here when it comes to their one-letter code, it can be a little bit tricky. Here we're going to determine their one-letter code by sounding them out phonetically. So if we say aspartic acid, aspardic, it sounds like there's a D within the description. So aspardic. So that's why we're going to say that its one-letter code is D. For glutamic acid, so glutamicmic at the end. So depending on how you say it phonetically it sounds like an E. Glutamic. So that's why we're gonna go with E here. So we have the one-letter code for aspartic acid being D and the one-letter code for glutamic acid being E. I put them in this order because I remembered as drinking acid you're going to the emergency room. Right? So here we're talking about drink D for aspartic and emergency E for glutamic. So that's why we list them as aspartic first then glutamic. Now for aspartic acid, what does it resemble? Well, here when it comes to aspartic acid, we're going to say that this carbon here is just connected to a carboxylic acid group. Remember, these are acids. Biological acids are carboxylic acids. It's just one example of a type of biological acid. So here, this carbon would just be connected to a carboxylic acid. This would be what aspartic acid resembles. Now for glutamic acid, it's a little bit trickier. We're going to say we don't have just one carbon, we're going to say this carbon here is connected to another carbon, and that carbon is connected to a carboxylic acid. Now, we can say here that these two carbons are connected together or glued together, because if you look you have glu and then E, they're glued together to help make glutamic acid. So that's the way I remember what glutamic acid looks like. I have my initial carbon in red. It's going to be glued to another carbon, and it's that carbon that's connected to a carboxylic acid. Right? So right now, we've learned two ways of finding out what our acidic amino acids would be. Next, we have our basic amino acids. Basic because they have basic side chains. Now, here they are lysine, they are histidine, and there are arginine. So here again, the three-letter code is based on the first three letters in their name. So if we look here we have lysine, LYS, histidine, HIS, and then Arginine is ARG. Here when it comes to their one-letter code, it's a little bit trickier. So what do I say to myself to help me remember this? Well, I kind of think of an old cartoon I used to look at when I was smaller. It was based on this basic idea. So basic basic side chain. This basic idea of a cat and a mouse, and the cat would always try to catch the mouse, but could never do it. That's Tom and Jerry. So I'm kind of giving my age a little bit, but I kind of go with this idea of Tom and Jerry to help me remember the basic side chains of amino acids because it's a basic concept. We're gonna say here that KHR stands for kittens hunt rats. So this idea again is a play on Tom and Jerry, the cartoon show. Now here, if we take a look, we can say that for lysine LS or K, the way I remember that lysine is connected to K is that we can say that lysine is a liar, but that's okay. Alright. So what do we have here? We have Lysine is connected to K. So that's the way I remember the one-letter code for lysine. And if we were to take a look at lysine, we'd say that lysine resembles methionine. We're gonna say here, Lysine resembles Methionine. If we look at the alphabet we can say that L is next to M on the alphabet chart. So lysine resembles Methionine, so here we draw it as. Here go our carbons, and at the end because we're dealing with a basic side chain we'd have an amine group, so NH₂. So here this would represent lysine. For the next one, histidine, and arginine are a little bit trickier. Okay. So these, we're going to come up with other ways of recognizing them. Their one-letters are easier to see because with histidine, hist starts with an H. So for this one, we're going to say that this carbon is connected to a 5 membered ring. So what we're gonna do here is we're just gonna draw the 5 membered ring initially and then we're gonna we're gonna alter it. Because it's a basic side chain, we're gonna have the presence of nitrogen groups. We're gonna say that this carbon is connected to the 5 membered ring, and we're gonna pay attention to this carbon here in black. Now to draw this correctly, we're going to say that there's 2 nitrogens within this 5 membered ring. 1 of the nitrogens will be directly connected to that carbon in black and one of them will be one carbon away, so over here. The one carbon away is going to be double bonded because nitrogen ideally wants to make 3 bonds. So here we're going to put a double bond there, actually we're going to put these in blue keep up with the theme. And then the other nitrogen that's connected to that carbon in black, it needs to make 3 bonds as well, it's not double-bonded so in order to make its third bond it'll have a hydrogen branching off of it. So here, this represents histidine. It's basically our carbon in red connected to a 5-membered ring. The carbon in black is the one connected to that red carbon here. And it has 1 nitrogen directly connected to it and it has 1 nitrogen away from it. The one that's away from it is double bonded, the one that's next to it, connected to it, has a hydrogen and it's single bonded. Alright, so then those are those 2. And then finally here we have our arginine arginine. Depending on how you want to pronounce it. So here, this one's trickier. How do I remember_assigned_to_73_29_Start">what this structure looks like? Well, here we have ARG as its three-letter code, and we could think about where do I hear ARG? Argh. Well, you might hear argh if you bump your knee, hurt yourself, or step on a tack. So let's say you step on something sharp. Okay. And let's say you step on a tack. And you'll give out an expression of Argh! This hurts. Going along this theme is going to help us to remember what the structure of this amino acid resembles. We're going to say here that this amino acid, this carbon here will be connected to these carbons here and then that one will be connected to a nitrogen. In order to make its 3 bonds, it has a hydrogen on it. It's connected to a carbon which is double-bonded to another nitrogen. In order to make 3 bonds, it's single-bonded to a hydrogen. And then that double-bonded carbon is finally connected to its last nitrogen which is NH₂. Now, here we're thinking about stepping on something sharp pointing like a tack, something triangular at the top, and if we were to think of this triangular thing, this end here kind of resembles a triangle. So stepping on this amino acid is very painful. We're going to say here that this represents a triangle of amines. Triangle is for 3, and what do we have here? We have 1, 2, 3 carbons involved that are coming off of this red carbon, and then how many nitrogens do we have? We have 1, 2, 3 nitrogens. Okay, so that's a way of us remembering what the structure of this amino acid resembles. So let me erase all these circles. Okay. So that would be our final structure. So remember, when it comes to our acidic and basic amino acids based on their side chains, to remember the 2, just remember drink acid, you're going to the emergency room. So here D is for aspartic acid and E for the emergency room is_ss">is for glutamic acid. Then based on my childhood cartoon, Tom and Jerry, we're going to say that kittens hunt rats and we're going to say here that K is for Lysine, H here is for histidine, and then we have an R here for arginine arginine. So that's how we can remember the different types of letter coding for the amino acids. And then just remember some of the tricks that I talked about when it comes to their structures. We have our aspartic acid, which is just that carbon in red branching off to a carboxylic acid. Glutamic acid, where that red carbon glues itself to another carbon which that carbon is connected to a carboxylic acid. And then we have our lysine has a structure similar to methionine. We have our histidine is just a red carbon connected to a 5-membered ring. And then we have finally arginine arginine, that's a painful arc. Think of a triangular tack where you step on it. It's made up of 3 amines, so we have 3 carbons and 3 nitrogens. So keep that in mind when examining these different types of amino acids.