Amino Acid Catabolism: Amino Group - Video Tutorials & Practice Problems
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concept
Amino Acid Catabolism: Amino Group Concept 1
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In this video, we'll focus on amino acid metabolism in relation to the amino group. Now, here we're going to say the first stage of amino acid metabolism is the removal of the amino group in the liver. Now, this is a two step process. We're gonna say process A is called transamination. Process B or process two is oxidative deaminate. Now, if we take a look here, we see that we have our macro molecules of proteins, carbohydrates and lipids. You're paying close attention to the digestion of proteins. So we're seeing how that creates our amino acids within our cytosol. Here, we're gonna see that our amino acids through transamination, we have the removal of the amino group and that occurs within the cytosol. Here. If we take a look, our amino acid A, we have transamination, we see that we can have the formation of what we call an alpha keto aid. We'll go in greater details of this. This is just a broad overview of what's going on. We're gonna say here through transamination, we also have the generation of what's called glutamate. This occurs within the mitochondria. And here we're looking at the mitochondrial matrix in which, where, where it occurs. Now, here, once we have our glutamate, we go into the second part of this process which is oxidative deaminate. This is the formation of ammonium ion which is NH four positive. And again, it's occurring within the mitochondria. So, through oxidative deaminate, we have the formation of the ammonium ion. And then we also have, if we cross the mitochondrial membrane back into the cytosol, we have the alpha ketoglutarate being produced as well. So here we have stage one, stage two is occurring within the cytosol. We're gonna say here that part of this traverses across the mitochondrial membrane into the mitochondrial matrix where we have glutamate the production of a moon. And then going back across the mitochondrial membrane, we have our alpha ketoglutarate. So just keep in mind when it comes to amino acid metabolism in relation to the amino group, we have transamination and then oxidative de deaminate.
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concept
Amino Acid Catabolism: Amino Group Concept 2
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Hey, everyone. So in this video, let's talk about transamination. Now, first, we're gonna say that it is a reversible reaction. And we're gonna say here in transamination, we're gonna say the amino group of the amino acid and the keto group of the alva keto acid are exchange. If we take a look here at our reactants, remember this is our amino acid because it has the four parts that make it an amino acid. We have our carboxyl group, we have our amino group, we have our alpha hydrogen here and then we have our, our group here. What makes this an alpha keto acid? Well, here's an acid because it has this carboxyl group that can be acidic. And then remember alpha, this carbon, the C double Wando, that's part of this structure that I circled. That is our main carbon. The carbon next to it is our alpha carbon. So this is our alpha carbon that alpha carbon is a carbonel as well. That's why we call it an alpha hedo as it's a keto. And then we have our, our group. Now the exchanging between the amino group and the keto group is accomplished with the use of our enzyme. That enzyme is transaminase. You might also hear it being called amino transferase. OK. So either term could be used for it. So again, we say that this is an exchange. So all that's happening is this group and this, they're exchanging their swamping. What's the result of this? Well, here we have our new carbon here to create our new alpha uh keto aid. And then we have our new, our, our ammonia amino group being put here to create our new amino acid. Now, what's the takeaway from here? We're gonna say the alpha keto acid is usually an alpha ketoglutarate and that produces glutamate as the new amino acid, right? So that's the key takeaway from transamination. We have the exchanging between an amino group and a keto group.
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example
Amino Acid Catabolism: Amino Group Example 1
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In this example, it says complete a transamination reaction for aspartate. Remember what happens here is we have the exchanging between an amino group of the amino acid and the keto group of an alpha keto aid. If we take a look here, here is our amino group of this amino acid and here is our alpha carbonel group of this alpha keto acid. Remember it is the double bond O that's exchanging, right? So they're kind of swapping places. So what effect would this have? Well, here we have our reversible arrows because remember this process is reversible, we would show this first one, we still drive it. So we still have this portion with the H up here ch two. And then this, remember we're swapping. So now this oops and actually this carbon needs to make four bonds. So it loses that hydrogen too. We'd have our double bond and then o here. So this is our new group being formed. Plus we're gonna say we have this other one now is transformed. We'd have our NH three positive here. Carbon still needs to make four bonds. So it also have an eight year as well. So this will represent our two products being formed through transamination when we're dealing with aspartame.
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concept
Amino Acid Catabolism: Amino Group Concept 3
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In our continued discussion of amino acid metabolism in relation to the amino group, we're not gonna look at the second step or phase b of our process. Here, we're talking about oxidative deaminate. Now, here we're going to say that the glutamate, it's going to be oxidized back to an alpha ketoglutarate by ND positive. This is gonna help form our ammonium ion. The ammonium ion itself then enters the urea cycle. If we take a look here, we have our glutamate as a reactant plus water. We're utilizing our enzyme glutamate dehydrogenase. Remember naming the enzyme is easy. It's the name of the substrate which happens to be glutamate glutamate because this is an oxidation. Remember that we utilize the class of enzymes called a dehydrogenase. Here we have N ad positive N ad positive is reduced to N A DH A high energy molecule. N ad positive being reduced is what causes glutamate to become oxidized. So what's going to happen here? We're gonna transform it into an alpha ketoglutarate. This carbon now is gonna have the carbon neal and remember we're all gonna produce our ammonium ion. These will represent the products formed within this oxidative deaminate and they would be our final answer.
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example
Amino Acid Catabolism: Amino Group Example 2
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In this example question, it says complete a transamination and oxidative deaminate reactions for three. Now, here's the thing threonine is just one of those unique amino acids as well as prolene and lysine that don't undergo transamination, prolene and lysine don't undergo transamination because they lack the alpha amino group threonine though it doesn't do it because it will create a dimer toxic type of structure. But let's just forego that limitation and just imagine that if it were to go undergo transamination, what would happen? Now, remember in transamination, the way it would work is we'd say that this serves as our amino acid. We'd have to react it with an alpha keto acid. And here's our alpha keto acid. Remember with this alpha keto acid through transamination, we would basically exchange the amino group and the keto group. So this would change this amino acid into this new alpha keto acid and we make a new amino acid here. So this new amino acid would look like this. Remember this new amino acid that we make is glutamate glutamate itself would then undergo oxidative deaminate. So here we're gonna bring it down here since this is gonna represent glutamate. We're gonna write in what this R group represents. So for glutamate, it would be our carboxyl group and then we'd have our two ch, two groups. We have our ch here, here's the amino group that was added. Here's our other carboxyl group. Remember we reacted with water as well. We use N ad positive become N A DH would use glutamate dehydrogenase in order to do this oxidation. So all that happens here here is still our car box. And this NH three, this amino group is transformed into a carbon. This would help to create our alpha keto uh blue. This would be our final product here. So this would be our final answer.
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Problem
Problem
What amino acid yields the following α-keto acid through transamination?
A
Lysine
B
Methionine
C
Cysteine
D
Glutamate
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Problem
Problem
Drawα-keto acid produced by transamination of glutamine.
A
B
C
D
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