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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 1


Amino Acid Oxidation 1

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let's begin by talking about amino acid oxidation, which is how the body uses the carbon skeletons from Minot acids to fuel the citric acid cycle. Now, before it can use those amino acid carbon skeletons, it needs to do something about the nitrogen needs to get rid of them. But it can't just cut them off and release them as ammonia to the cell because that would really mess with the cells. PH and also could be toxic to the cell. It's a reactive species. Anyhow, what the cell is gonna do is gonna take those nitrogen, and it's gonna put them through the Yuria cycle, which is a cycle that occurs in the liver. So it's gonna export this stuff to the liver, and the cycle takes in two nitrogen zones and puts out one Yuria, and it costs three ATP to do this. So we're gonna take a look at the cycle right here, and the first step, or what you could think of as the first step, which is right here, is going to occur inside the mitochondria. So this here is inside the mitochondria with matrix, and out here we have he site is all and what's gonna happen is carbon Malil phosphate. Since the taste, this enzyme right here is going to take bicarbonate. And this should be an ammonium because right, it's dissolved in the cells. So this figures a little mistake, but you can see that up here that it's ammonium and it's gonna take bicarbonate in ammonium and at the cost of to a teepee form this molecule right here, which is carbon real phosphate. I'm just gonna write carbon wheel p its carbon wheel phosphate now or in Athene is going thio enter the mitochondria and or nothin is this molecule right here? That's or anything it's gonna enter the mitochondria and it is going to combine with carbon wheel phosphate and that phosphate groups gonna leave, you can see is an organic phosphate, and they're gonna combine to form this molecule right here. Citra lean Now Citra Lien is actually going to then exit the mitochondria. So a little back and forth in here, it's gonna exit the mitochondria and then things get a little interesting. What's gonna happen is ATP is going to be broken down to you Higher phosphate, of course pyre. Phosphate taste is going to break this down to you to inorganic phosphate and Citra Lien is going to be combined with a Spar Tate and what's actually happening. You see this? A m P Let me jump out of the image here. Heads blocking it. You see this? A MP right here. Basically, uh, the A m P. Gets attached to the enzymatic intermediate Theus. Part eight is added in the A M P leaves. So that's why you see the A m. P coming off a little later here before that pyro phosphate. So these come together and they form this molecule right here. Arjuna six and eight. Uh huh. All right. Oh, I'm sorry. I'm not labeling my steps. So we had step one. This here was Step two and this was step three. Okay, So Arjuna of six and eight is then cleaved into you. Humor ain't right here. And Argentine right here. And that is step four. And from there, Argentine has Yuria removed from it. Right? So basically this these nitrogen is right here are coming off as Yuria and what we're left with is or in a theme again, right here. So that is our final step of the Stichel. Step six. And then, of course, that Oren Athene will re enter the mitochondria, combined with carbon memorial phosphate. And the cycle will repeat itself. Um, so let's turn the page.