Metabolism | Fatty Acid Oxidation: Part 1

I'm engineers in this video we're going to talk about fatty acid oxidation so if you guys have already watched our video on the mobilization of fat that's going to really help you understand where we're going from here so we said and the mobilization of specifically the facts where we were breaking down that triglyceride into its components glycerol and fatty acids we were taking those fatty acids into different tissue cells what can those tissue cells be that we're taking it to again we said three really important ones we're going to be heart muscle so the heart muscle is going to be a big one so the myocardium of the heart the skeletal muscles and even the liver okay so even the liver many many different tissues will utilize these fatty acids for energy but the big ones are going to be your muscle and some of even the liver and you're going to see why the liver is really important because it can generate these structures called ketone bodies but we'll talk about that okay so now we brought the fatty acids into this actual cell now let's say this is some general cell and we're going to bring fatty acids into it all right so let's show here our fatty acids let's show these in blue okay here's our fatty acid we bring these fatty acids from out here so again here is going to be our free fatty acids what's going to happen is let's take for example these free fatty acids and say that they are specifically long-chain fatty acids so these are specifically long-chain fatty acids so approximately about 16 carbons long okay so let's say we bring in a specific type of one and one of the more specific 16 carbon fatty acids is called palma tow lake acid this is a 16 carbon chain what I'm going to do is I'm going to zoom on some of those carbons I'm not going to look at all 16 carbons so what I'm going to do is I'm going to put an R group here and I'm going to have a couple special carbon so let's say here is my fatty acid portion so here's my carboxyl end right next to that I'm going to have another carbon and that's going to be my L carbon and I'll have one more carbon next to that one which is going to be my beta carbon and then next to that I'll have many many other carbons so in this case this would be 1 2 3 the rest of them would be humming 13 carbons long so if I wanted to I could continue to put all the way down 13 carbons long but I'm just going to make it in our group now the first thing that's going to happen with these free fatty acids is we have to prevent this fatty acid from getting out of the cell so in order to do that we're going to use like utilize a special enzyme so what's going to happen is this free fatty acid is going to be acted on by special enzyme this enzyme is called fatty a seal co a synthetase and what this enzyme is going to do is it's going to trigger the conversion of this fatty acid this is the fatty acid okay we need to make sure that we can note specifically a fatty acid nothing on this guy but then this fatty a co co a synthetase enzyme is going to stimulate this reaction and in order for this reaction to occur we have to utilize energy this is going to cost energy to add that coal a on so I'm going to add a coenzyme a into this reaction but in order for me to do that it's going to cost energy what is that in the form of ATP so I'm going to break down ATP into ADP and inorganic phosphate and by doing that I release energy from the breaking of those bonds which adds the kolay onto this fatty acid as a result then what am I going to have over here then so now let's draw the resulting product so I'm going to have my R group here because here's my R group I'm gonna have my ch2 ch2 and then right next is my life carboxyl group but specifically bound to that carboxyl group is going to be a coenzyme a so right next to someone to have a coenzyme a right there and use it as having some type of Thile group okay now this new molecule that we just synthesized in this first step of this reaction is called a fatty a CoA so a fatty Aseel call a now here's the next problem so the first thing that we had to do is we had to put a CO a on this guy and let's make this a different color for the sake of let's make this one green since we had green therefore CO a let's they consistent there so here's our coenzyme a and again it has some specialized style rope on it and it's really important in this but if you remember we couldn't get this guy we couldn't keep it in the cell unless we put a co a on it okay well now we've got a Caillat on it now we got another problem we can't get this molecule into the mitochondria because of the co a now I got to do something specific that can actually transport it in okay there's another molecule this molecule is coming from this specific transporter this guy right here is adding on a special molecule to this guy okay what is this molecule that he's adding onto him he's adding on a molecule which is called carnitine okay so carnitine is going to combine with this fatty SCO collect and look what happens here so I'm going to bring this fatty a CoA down through and then what happens is this fatty of Silk Way is going to combine with what the carnitine when it combines with the carnitine it gets rid of the co a so now that co a is going to be lost okay so we did that reaction just to get rid of the co a hmm that's weird we'll see why so now we release the coenzyme a and we add in the carnitine as a result I'm going to form a molecule called fatty a seal there's no longer kolay it has a carnitine on to it carnitine so it's called fatty acyl attea sealed carnitine that fatty acyl carnitine can be transported through this structure this translocase and again what's going to come out on this side the molecule that we'll have on this side is going to be specifically look I'm going to have my carbon here and now it's going to be bound to it carnitine carnitine will be down to this what is this molecule here called this molecule here is called fatty a seal quarantine so here's the next problem having this fatty acyl carnitine you could easily go back out through that translocase because this is a bi-directional translocase so to prevent from him from getting back out guess what I have to do I have to rip that carnitine off and then add another coenzyme a back on to it okay so how do I do that you see this guy right here this enzyme this enzyme is going to take a co a so let's say he take this coli here he takes that co a coenzyme a and he adds that coenzyme a onto this fatty acyl carnitine so the adds is co enzyme a onto this fatty acyl carnitine but at the same time few rips off that carnitine so look what he does this enzyme is going to break this bond here and rip off that carnitine and then he's going to add on this call a and look what we get as a result of this reaction let's do this in pink here this is an important step here as a result what are we going to get then now the result is going to be again a fatty a feel group with a coenzyme a so now let's draw that so we're gonna have our R group ch2 ch2 carbon double bond oxygen and then again that's going to be bound to a coenzyme a over here now let's put our head either now next thing what happens to that carnitine that we ripped off the fatty acyl carnitine it's going to get pushed back out so this fatty acyl carnitine guess what's going to happen he can get pushed back out here and recycled now the question at hand is what the heck are these molecules that are doing this process this one right here that has two names this one are here on the outer membrane you know this is the mitochondrial matrix that we call this the mitochondrial matrix and then out here this is the outer membrane of the mitochondria out here is the cytosol on the cytosolic side of the mitochondria you have this transporter this transporter here is called carnitine a seal transferase type 1 ok so again what is this molecule here called this molecule here is called carnitine acyl transferase type 1 you know they also have another name for it since we're dealing with 16 carbon fatty acids they can call it carnitine palma payal so specifically carnitine pull metal transporter type 1 so you can see it as cat one or CPT one just in case you see it in the literature it can be references as carnitine acyltransferase type 1 or carnitine palmitoyl transferase type 1 just in case you see it in different literature's and that way right ok so what is he doing he's adding quarantine onto the fattiest CoA getting rid of the co a and then this fatty acyl carnitine structure is getting transported through this translocase into the mitochondrial matrix once in the mitochondrial matrix to prevent him from getting back out he has to be acted on by this enzyme who rips the carnitine off and pushes that carnitine back out into the cytosol via this translocase and then he this enzyme our transporter adds on a coenzyme a what is this transporter called this is called carnitine acyl transferase type 2 or again carnitine palmitoyl transferase type 2 now that we've done that what are we formed we're not even close to going and that's crazy we formed this fatty a seal color so from this step we formed a fatty a seal Co a then now we're going to undergo this next step so what was this first step that we just performed the first step was getting the fatty acid into the cells the next thing was activating it so this step right here is called activation so again what is this step right here called let's denote this this step right here holy crap this step right here is called activation so you're activating the fatty acid by adding a coenzyme a and converting ATP into ADP and inorganic phosphate and this reaction is catalyzed by fatty seok entities the second step is going to be the transport so how we're actually getting this specific fatty of silk away into the mitochondria so that we can undergo this next step this next step will spend most of the time is going to be called beta oxidation okay so now we're going to take this fatty seok way through a series of reactions the first thing that we're going to do we need to do know the nomenclature of this molecule so you see this carbon right here this is our number one carbon this is our number two carbon but sometimes we refer to the number two carbon as the alpha carbon and this is our number three carbon but sometimes we refer to the third carbon as the beta carbon and then you'll go on and on and on lon now here's what's going to happen in the first step of this reaction I'm going to remove a hydrogen from this guy and a hydrogen from this guy and an extra electron what do you call that whenever you have a hydrogen a proton plus two electrons it's called a hydride so I'm going to pull hydrides off of this molecule who is going to do that faad let's show this reaction so look what's going to happen in this step right here I'm going to have s ad come in so s ad is going to come in and pick up a high drive from this guy and a high drive from this guy and then that's going to turn into fadh2 what enzyme is catalyzing this step well this is a fatty of seal Co a so they call this a seal Co a and you know how you're having a specifically some type of coenzyme involved that are picking up hydrides usually that's a dehydrogenase so this is an ACL Co a d hydrogenase okay when this happens you're going to rip that hydrogen off of that hydrogen off and you're going to form a double bond to stabilize that molecule so now what am I going to I'm going to have a double bond between my alpha and my beta carbons let's show that as a result this is the first step so this is step one then as a result I'm going to have a CH here double bond here let's make that double bond a different color so that we very very are particular with distinguishing the difference here so now let's go ahead and click this in this color here this is our double bond there okay then on the other side I'm going to have a CH and then a carbon double bonded to an oxygen who's still bound to a coenzyme a okay that was the first step not too bad in the second step I'm going to do something weird I'm going to take and I'm going to add water across that double bond but in order for me to add water across that double bond I'm going to need an enzyme who can help me do that in other words I'm going to need an enzyme who can hydrate this so how do you do that so let's do this next step the next step of being oxidation step two is I'm going to hydrate this guy how am I going to do that I'm going to add water into this reaction so I'm going to take water and I'm going to add water into this reaction but in order for me to do that I need an enzyme who can feel silicate that reaction just like a CL co a dehydrogenase stimulated this step I need an enzyme that can stimulate this step that enzyme is called in oil co a hydratase now you're probably wondering where the heck did this email Caillat come from that's what this molecule here is called this molecule is called in oil co a so this molecule is called in oil co a but we have to be even more specific this hydrogen here really should be poking upwards this hydrogen here should really be poking downwards so now this double bond is having hydrogen's on opposite sides that's trans so technically and this is on between what this is the first carbon this is the second carbon that's the third carbon so we do know double bonds whenever we're doing nomenclature according to like I you pack that that's going to be where I put my double bond I mainly like that way so they call this trans because the hydrants on opposite side Delta 2 to signify that there's a double bond between the second in the third carbon so they call this molecule technically trans Delta 2 in oil Co a then once we have this trans Delta 2 in oil Co a what's going to happen he's going to get acted on by this e noil Co a hydratase this emu oil Co a hydratase is going to add water across this double bond and then you're gonna have an H here and you'll have an H there that's all it's going to happen because when you add water you add an O H to one side and an H to the other side so now install the resulting molecule as a result here in 1/2 R let's actually bring this up a little bit so actually bring this reaction up a little bit here bring this arrow this way guys and that's a little better ok this is again the second step now we're getting ready to enter into the third step so now we're going to have V again our group carbon hydrogen and then we're going to have that double bond I'll put that double one in just a second carbon hydrogen and again you have the carbonyl group and again what is bond to that carbonyl group coenzyme a with a sigh all what is going to happen in this step here ok so since we added the water now what should be the result I should get rid of that double bond that double bond should go away because I added water across it when I add water across it let's actually make this double bond like that now now let's put different colors on this that water I'm going to add an O H to this side to the beta carbon and I'm going to add a hydrogen to the alpha carbon so again what is this carbon right here this is number one carbon alpha beta carbon because the hydroxy group is on the beta carbon of this fatty estilo a we call it beta carbon so the beta carbon of the third carbon beta hydroxy a co co a that's how you call it not a hard molecule to name right so again what do you call this molecule beta hydroxy asil KO a molecule and that is formed by this email KO a hydratase adding water across this double bond now we have another step we're going into the third step there's three there's four steps total and I'll give you a mnemonic that helps you to remember it very easily okay then in this third step of the reaction I'm going to bring in an enzyme who's going to help to have NAD+ turn into NADH and what that's going to do is you see this o H here and you see this H here what this enzyme is going to do is it's going to do something very very cool this hydrogen right here I'm going to circle this one he's going to take that one and he's going to take this one that and any positive so the entity positive is going to come over here let's say here we have a in a D+ he's going to get converted into in a d H and he's going to pick up some high drives when he picks up those hydride ions this carbon has no choice but to form a double bond between that oxygen right there I'm going to lose that hydrogen and that hydrogen as a result what am I going to have then as a result let's let's draw on here this guy is going to have to have a double on carbon - I mean double on oxygen we'll show that in a second this guy's still going to have his hydrogen's we're still going to have the carbonyl and that carbonyl is still going to be bound to a coenzyme a with the final group but what's the difference now now we're going to have a double bond between this oxygen here double bond between an oxygen and this hydrogen is left alone what do you call this molecule okay well now there's a ketone because there's a carbon here a carbon here so that's a ketone on the beta carbon because again this is one alpha beta so if the ketone group is on the beta carbon and this is a fatty acyl group with a co a they would call this beta Kido a seal Co a caddis molecules call beta keto is seal Co a and the enzyme that's driving this step very cool and on what did I tell you guys if you ever see it nad going to NADH you always know that there's a dehydrogenase present so just say the name of this molecule and then put dehydrogenase after that's it this enzyme is called beta keto a seal specifically beta keto at seal Co a dehydrogenase okay so we have a beta key to a co co a dehydrogenase who is stimulating this step in doing what converting this alcohol group dis beta hydroxy a Co Co into a beta keto a Co Co a now we go into the fourth and final step okay what's going to happen here is I'm going to take something in special enzyme this enzyme is very very special this enzyme is called thiolase and what this violates enzyme is doing is it's doing two things in this reaction okay one carbon alpha carbon beta carbon right if I were to come over here for a second I want to just expand on that our group for just a little bit I could technically draw another ch2 and another ch2 and I'll just put an R group here for a second now this is one alpha beta carbon you know what I can technically call these afterwards after what I'm going to do in this step here is I'm going to cleave this bond between the Alpha and the beta that's my goal in this step I'm going to break this bond the bond between alpha and the beta carbon when I break the bond between the Alpha and the beta carbon I'm going to release out what acetyl co lay but then the problem is I have this whole fatty acid group that is going to be you know what am I going to do with him I'm going to add in Akko a so what happens in this step here if thiolase is going to cut this bond right here between the Alpha and the beta carbon and at the same time he's going to add a co enzyme a but to who to the beta carbon after this bond is broken so now look what two products we get out of this so I'm going to share one product going up and one product coming over here so as a result I'm gonna get two products one product I'm going to show is going to be this side okay so now if I show you this side of that broken bond I'm going to have it our group ch2 ch2 and then this is going to be a carbon with a double bond oxygen because all I'm gonna do is just draw double one oxygen there and then what did I say this tie lace is adding that coenzyme a onto the beta carbon after this bond is broken so what am I going to see right here co-enzyme a with the final group this is a new fatty of silk away where is this fatty of silk away gonna go guys let me show you this fatty of silk relay is going to go back over here and get recycled English is going to go through another round of beta oxidation now the question at hand is why do they call a beta oxidation because what I was doing is I was breaking the bond between alpha and the beta carbon I'm breaking that bond and I'm releasing out a fatty a co co-ed so this is a regenerated fatty of CoA it's just two carbons short so this is a fatty a seal Co a and all it is is just two carbons short but it'll go and get broken down again and it will go from 16 now it's going to be 14 so this is a 14 carbon how do you ever go through it again it made 12 go through it again make 10 you guys get the point what's the other product of this reaction because I said there was two products okay the other product now I'm going to show this side what's going to happen is this carbon is going to pick up a hydrogen or pick up a hydrogen and you're going to get a ch3 group so that's going to be this carbon does their alpha and then right next to it I'm going to have the carbonyl group and what's bound to that carbonyl group co-enzyme a with a soil component what is this molecule called this molecule you guys have seen many many times this is called acetyl co a you might not have seen him like this in this form but you've heard of him and he is a two carbon molecule what can happen with this acetyl co a you guys already know it can happen he can do what he can go and enter into a specific cycle what is that cycle guys the krebs cycle out of the krebs cycle what can i generate from the krebs cycle so from this guy right here this acetyl co a what can I do with him I can bring him into the krebs cycle he can be reacted in the Krebs cycle and then what happens you produce what NADH is fadh2s and a little bit of ATP what can happen with these NADH is these fadh2s they can take it to the electron transport chain and lead to oxidative phosphorylation to where the overall result is going to be what ATP formation because remember I told you guys what was the original problem of why we were doing this whole beta oxidative process the whole reason we were doing this beta oxidative process because our blood glucose levels in the blood we're low if our blood glucose levels are low it means we're fasting I mean that we don't we're either not taking in enough carbohydrates into our diet may be doing a ketogenic diet like some type Atkins diet or maybe you're having uncontrolled diabetes mellitus and you haven't taken your insulin whatever it might be your body needs another fuel source so your primary fuel source is carbohydrates but when that is not available your body reverse to the secondary fuel source which is fats and so it starts breaking down fats to make what a seat okay I can't stress how important this whole process is because the whole overall result depends upon this right here that the whole significant purpose of beta-oxidation is to produce two carbon fragments at a time which is going to be called acetyl co a now the last question is if we take a 16 carbon fatty acid let's say I take that 16 carbon fatty acid and I run it through beta oxidation 16 carbon fatty acid and I run this 16 carbon fatty acid through beta oxidation the question is how many acetyl COAS will this produce well I told you to chop it into two carbon fragments at a time if it chops it into two carbon fragments at a time how many acetic ways am I gonna produce then I can produce up to eight acetyl co a x' Wow and then with a to see turquoise imagine how many nadh and fadh2 is we can produce we're going to do that in another video when we calculate the total energy yield of how much a 16 carbon fatty acid how much ATP can actually produce it's insane now the next question is this sometimes gets people how many rounds of beta oxidation actually occurred this is a tricky one some people will be like oh well you make a to see the clay start with 16 you do it eight times no it's seven rounds of beta oxidation the reason why is think about it like this guys let's come over here for a second let's add draw this for a second so one two three so we got one two three four five six seven eight nine 10 11 12 13 14 15 16 if I start right here and I cut each one of these pieces here this is we're going to call this the number one carbon and this is going to be this 16 carbon right and I'm chopping them into two carbon fragment so this is one and two so I'm going to copy up here then I'm going to go one two chopped here one two chopped here one two chopped here you guys get the point I'm going to chop here how many cuts did I make I made one two three four five six seven cuts on this molecule because when I cut this thing vii time let me actually do this one in a different color when I cut this thing the seventh time what am i doing I'm breaking this four carbon fragment into two two carbon fragments so that's why sometimes certain professors will say how many rounds a bit oxidation did you do for a 18 carbon fatty acid just put the number of acetyl co a smite us one that's how you figure it out so if they ask you you say they say they take a twenty six carbon fatty acid undergoes beta oxidation how many acetyl co a will produce you just figure out okay if it's twenty six I'm going to divide that by two so I get 13 acetyl co a x' minus one that's going to give me twelve rounds of beta oxidation okay guys in the next video we're going to talk about the energy yield and we're going to talk about certain other types of fatty acids that being odd chain fatty acids and also there is another process of beta oxidation that can occur in peroxisomes so in the next video we're going to talk about odd chain fatty acids being broken down we're going to talk about the beta oxidation that can occur in peroxisomes and the energy yield that can come from all of this oxidative process

Channel: Ninja Nerd

Views: 300,453

Rating: 4.9552603 out of 5

Keywords: fatty acid oxidation, metabolism

Id: OyQ1cgBw8HA

Length: 29min 40sec (1780 seconds)

Published: Tue May 30 2017