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

Oxidative Phosphorylation 4


Oxidative Phosphorylation 4

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So the whole point of performing electron transport right where we're moving electrons through the inner mitochondrial membrane through these complexes and pumping all of the's protons. The whole point of this is to build a proton radiant right called the Proton Motive Force. And this is an electrochemical radiant meaning that it has both an electrical component and a concentration component. And this Grady int is actually going to power the enzyme ATP synthesis, which drives thesis inthe ASUs of ATP from ADP and inorganic phosphate. And this is different from the substrate level phosphor relation that we saw in the glitch IQ and citric acid cycle reactions. This is actually what is known as the proverbial oxidative phosphor relation. Right. You have substrate level phosphor elation. And this right here is oxidative phosphor elation. Anyhow, before we get to how a teepee sent this works, it's important to also think about where the ingredients come from. Right now we know how the Proton Motive forces built. We just talked about that extensively. But how does all the ADP and inorganic phosphate get into of the mitochondrial matrix? Well, a deep comes in through an anti porter called Adnan nucleotide trans low case. So that actually moves. And this is brilliant. I love this. It's just another one of those really eloquent, subtle biochemical things. It moves ADP in while it takes ATP out right brilliant anti porter that moves these molecules in out of the mitochondria for essentially zero energy cost. Now, phosphate trans low case brings in the inorganic phosphate that you need, and it does that by actually using the proton radiant. It's taking advantage of the Proton Motive force that ATP synthesis uses to bring in organic phosphate in. So it's a sim Porter pulls in a proton as it pulls in. Inorganic phosphate, super eloquent, super beautiful. I love it when things work out so simply in biology, so a teepee. Synthes. This is probably one of the craziest enzymes you'll ever look at, and that's because it essentially a molecular motor. More or less. I mean, you have to portions of it. You have the F zero portion, which is gonna be embedded in that inner mitochondrial membrane that's right here. And then you have the F one portion and the F zero portion spins, as you can see right here, it spins around. I don't know if you can see this arrow that's in this image to coming around like that. Anyhow, I don't know why they did it in blue. It makes impossible to see. But anyhow, the F zero portion spins around and it's connected Thio, one of the sub units of the F one portion. It's connected to the gamma sub unit, and I don't know if you know anything about cars, but the gamma sub unit is basically a drive shaft. It gets spun around by F zero, and it causes confirmation. All changes in these Alfa and beta subunits. And it's within these, uh, beta subunits that the magic happens. That's where the A. T. P. Is synthesized. So what is going? Oh, and just to be clear, the F one portion has three Alfa and three beta subunits. I don't know if you can see that beta subunits kind of hiding behind the Gamma right here. Anyhow, the F one sub unit, as I said, experiences confirmation all changes due to the rotation of the drive shaft or the rotation of the Gamma sub unit, and basically, at any one time, each of the three beta sub units is is in a particular confirmation, so one is always open. One is always loose and one is always tight. And what that means is, when it's open, it can release ATP, and it can take in ADP and inorganic phosphate, right? So it's gonna release the teepee that's in there and pull in some ADP and inorganic phosphate. Then, when it's in the loose confirmation, the enzyme is going to hold those two substrates together in such a way that they form ATP. And that is, when it becomes for it enters the tight position where it is tightly bound to ATP. And this is essentially what requires the energy of the Proton motive. Forsett's not actually this part. It's the energy is mostly needed to release this tightly bound ATP. It's that shift from the tight state, the open state that is most difficult. So if you can see the individual sub units are color coded. So these air not actually moving. This is Gamma right here. This blue paddle right here and you can see that gamma is moving around counterclockwise, so it spins around counterclockwise, and it causes these confirmation all shifts in the sub units that caused them to synthesize the ATP. And again, it's actually the release of the 80 p. That's really, uh, needs the energy of the Proton Motive force in this whole process. This whole process that we've been talking about this whole time all leads to this moment of oxidative phosphor relation. It's been a heck of a journey. We're not quite over yet. So let's turn the page and finish up talking about photo phosphor relation, which is a really cool related process to this.