Pearson+ LogoPearson+ Logo
Start typing, then use the up and down arrows to select an option from the list.


Learn the toughest concepts covered in Biochemistry with step-by-step video tutorials and practice problems by world-class tutors

Review 4: Amino Acid Oxidation, Oxidative Phosphorylation, & Photophosphorylation

Amino Acid Oxidation 2


Play a video:
Was this helpful?
So how does the liver get amino acids to perform the Yuria cycle? Well, most amino acids are going. Thio actually come in as glutamine. Basically, all the tissues in your body are capable of delivering glutamine to you. Deliver thio. Get rid of that nitrogen so glutamine Synthe tastes is the enzyme that makes glutamine to send the liver. And basically it'll take glutamate and ATP and a nitrogen group, and it'll make glutamine. And of course, you'll be left with ADP and inorganic phosphate. And basically the reason for this is that it's very easy for the sell to convert amino acids into glutamine this way. So that's how it's going to transport the majority of amino acids to liver, and it also can get rid of this extra nitrogen group by doing so. So glutamine enters the mitochondria and we'll actually get broken down into glutamate. So kind of undoing what happened up here. And it'll cleave off that ammonium, and this is carried out by an enzyme called glute ham anus. Now that glutamate will then be acted upon by glutamate di hydrogen iss, and it'll be converted. Thio Alfa Akihito glued a rate, um, basically glutamate di hydrogen. It's just cuts off that, uh, cuts off that amino group, and it comes off his ammonium. And in the process, it's actually going to reduce N a D plus or an a D p. Plus. That's why the P is in parentheses. There it's it's actually either or, and it's going to reduce that to N a. D h or N A. D. PH. Now, um, these nitrogen that got cut off those are going to be used to feed the Yuria cycle. Remember that the first step requires ammonium to form carbon well, phosphate. It should be noted that some glutamate is actually used. Thio add the ammonium instead of just cutting it and releasing it to the Yuria cycle. That ammonium is actually added thio, xolo acetate and that forms a Spartak. Now, you might remember that during the recycle in a step three we actually use a Spartak. Guess what? That s part eight. Is this Spartak? So some glutamate is actually used to form the s part eight that is used during the Yuria cycle. And of course, the cell has to kind of regulate the amount of glutamate that it cleaves to provide ammonium and the amount it uses to form a Spartak. And it's worth noting that this is going to happen in the mitochondria, which should make sense, right, because we have Axler acetate. So then this ESP our tape has to actually be exported from the mitochondria into the site is all four step three of the area cycle. Now, I said that, uh, most tissues or rather, all tissues export glutamine but muscles, muscles actually consent Alan Enas. Well, this is called the Glucose Alunan cycle, and again on Lee occurs in the muscles, and basically, muscles will send Alan in to the liver. And the way they do that is by converting Piru of it into Alan, I mean, and to provide the amino group for this They're going thio Cleve glue to me, right? They're gonna take the amino from glutamate. So glutamate is going to turn into Alfa Kita glued a rate now that Alan in gets transported through the blood to the liver and once and liver. What happened in the muscle? What we just talked about up here gets undone. And that's kind of a pattern in general that I hope you're you've started to notice and they're gonna notice later that a lot of processes air done and then undone after some transport. Anyhow. So, Alan, I mean, gets converted back into Piru bit by sending that amino group over to Alfa Keto gluten rate, which reforms glutamate. And then that glutamate can be used for the Yuria cycle. And again, it can be used either by contributing ammonium to the recycle or by being used to make a smart tape. Now, what's gonna happen to that? Piru. Well, remember, this is the liver, the site of glucose neo Genesis. Right? So we are going thio, use Piru of eight or we can use pair of it, I should say, for glucose neo Genesis, which is gonna make glucose right? And then guess we're a lot of that Glucose is going right back to the muscles right now. This is why this is called cycle. Because that glucose goes back to the muscles, it gets broken down into piru of it, and then we can use that pair of it to make a linen and repeat this cycle. So before moving on, I just wanna get my fat head out of this picture and just zoom in on the liver for a second and show you what's going on here so way have a leonine and glutamine being used to make glutamate to feed furious cycle. Of course, if you're using glutamine to make glutamate, you're going thio cut off a nitrogen from it, which will be released as ammonium. And if you use glutamate, you can use it to either provide ammonium or a spar Tate right to the Yuria cycle. Right. So you may have noticed that FEMA rate also came off of the area cycle. Well, the recycle is connected to the citric acid cycle, right? It's happening in part in the mitochondria, so it's very easy for that huma rate. Thio actually enter the citric acid cycle where it will be turned into male late in the Knox Allah acetate. And of course, that Axler acetate, as we previously discussed, can be used to make a spar tape. Right, that is Theus, part eight that we saw right here. You Spartak that is used as part of the curia cycle. So in a sense, Arjuna sucks in. It is kind of the link between the citric acid cycle in the area cycle. Of course, here we way have it says T c A cycle which is the same thing as the citric acid cycle. All right, Last thing I want to talk about is Trans am in aces. Thes are used throughout this process. Right. Whenever we're moving an amino group from one molecule to another, we use a Trans Am anus and these always go amino Quito, two amino keto. And what's interesting about this is they can actually be an indicator of tissue damage. Really easy indicator of internal tissue damage. Because if you have internal tissue damage, enzymes will be spilling out and you can ask safer these Trans Am in aces Thio see where the tissue damage is, depending on which trans am in aces you have. So these Trans Am in aces right here, G p T and G o t indicate liver damage, and this s just means serum as an in the blood. And this trans am in a C rate here can be the indicate a indication of heart damage. So either you know, imminent heart attack or heart attack or infection. Last thing I want to talk about before moving on is regulation of the Yuria cycle. So remember, Step one is carried out by carbon wheel phosphate Synthe tastes, and this molecule and acetyl glutamate actually stimulates that enzyme so it can kick the Yuria cycle into gear. And the way that's gonna happen is with this. Basically, it's like a regulatory enzyme, sort of similar or kind of akin to what we saw with phosphoric kindness to so n asked, he'll glutamate synthesis will take acetyl coa and glutamate and make an ass till glue to me. And this enzyme that produces the molecule that stimulates three Yuria cycle is stimulated by Argentine. And I hope that this makes a lot of sense to you, right? Why would Why do you think Argentine would stimulate the Yuria cycle? In essence, right? I mean, it's a few steps removed, but basically Argentine can stimulate. The recycle is what we're seeing. Argentine has a lot of nitrogen, doesn't it? Well, hopefully you're putting two and two together, and if you have a lot of nitrogen, you're going to you want Thio, kick that Yuria cycle into gear. All right, let's flip the page