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Another procedure, gel filtration Chromatography, in which we separate the proteins based on size. And so following that, we extract that sample, we place it into this weld, and this is the band that we get. And so this band disappears, other bands disappeared. So what that means is we're slowly purifying the protein where we're moving those unwanted proteins as shown by padded increase in the band distribution number. So that is what should be shown by this table. So let's calculate this box. | Analysis of Protein Purification (Part II).txt |
So what that means is we're slowly purifying the protein where we're moving those unwanted proteins as shown by padded increase in the band distribution number. So that is what should be shown by this table. So let's calculate this box. In this box, as always, the specific activity is 85,000 divided by 100. The two zeros cancel out and we have 850 divided by one and that gives us 850. Now, what about this quantity? | Analysis of Protein Purification (Part II).txt |
In this box, as always, the specific activity is 85,000 divided by 100. The two zeros cancel out and we have 850 divided by one and that gives us 850. Now, what about this quantity? So to calculate this, we simply take this divided by that. So the specific activity of that mixture divided by the original mixture and we get 85. So because this divided by this gives us 85. | Analysis of Protein Purification (Part II).txt |
So to calculate this, we simply take this divided by that. So the specific activity of that mixture divided by the original mixture and we get 85. So because this divided by this gives us 85. And let's use purple for that. Okay? So what that means is this extracted mixture, following these processes up to this point is 85 times as pure as this initial mixture. | Analysis of Protein Purification (Part II).txt |
And let's use purple for that. Okay? So what that means is this extracted mixture, following these processes up to this point is 85 times as pure as this initial mixture. And finally, let's carry out the final one. So in the final step, in step E, we take our extracted mixture of proteins and we expose it to affinity Chromatography. And in affinity Chromatography, we separate our proteins based on their specific ability to bind to these special molecules. | Analysis of Protein Purification (Part II).txt |
And finally, let's carry out the final one. So in the final step, in step E, we take our extracted mixture of proteins and we expose it to affinity Chromatography. And in affinity Chromatography, we separate our proteins based on their specific ability to bind to these special molecules. And this usually creates a very high specific activity value because as we know, enzymes only bind to specific substrate to specific molecules. So let's see if that's true by taking the extracted mixture and placing it into our last well. So what we produce is a band distribution that only contains a single band. | Analysis of Protein Purification (Part II).txt |
And this usually creates a very high specific activity value because as we know, enzymes only bind to specific substrate to specific molecules. So let's see if that's true by taking the extracted mixture and placing it into our last well. So what we produce is a band distribution that only contains a single band. And what that usually means is we have isolated that protein of interest because this band consists of a protein that has a specific type of mass, a specific type of size. Now let's owe and by the way, let's calculate what the yield in this case was. To calculate the yield, we follow this equation. | Analysis of Protein Purification (Part II).txt |
And what that usually means is we have isolated that protein of interest because this band consists of a protein that has a specific type of mass, a specific type of size. Now let's owe and by the way, let's calculate what the yield in this case was. To calculate the yield, we follow this equation. So this divided by this gives us 85 divided by 200, which is 42.5 divided by 100 multiplied by 100, that gives us a percent of 42.5. Okay? So let's go back to this step. | Analysis of Protein Purification (Part II).txt |
So this divided by this gives us 85 divided by 200, which is 42.5 divided by 100 multiplied by 100, that gives us a percent of 42.5. Okay? So let's go back to this step. So this basically means that we have successfully isolated that protein. We basically have this protein that consists of a single type of mass. Now let's see that the specific activity increases and this increases. | Analysis of Protein Purification (Part II).txt |
So this basically means that we have successfully isolated that protein. We basically have this protein that consists of a single type of mass. Now let's see that the specific activity increases and this increases. And let's make sure that the yield didn't decrease by too much. So if we have at least 30% here, that is a good procedure. So let's take a look at E to calculate this. | Analysis of Protein Purification (Part II).txt |
And let's make sure that the yield didn't decrease by too much. So if we have at least 30% here, that is a good procedure. So let's take a look at E to calculate this. We take this divided by two and we get 35,000. So we see that in fact, this procedure has a high specific activity. And that makes sense because affinity Chromatography separates these enzymes based on their ability to bind to specific enzymes. | Analysis of Protein Purification (Part II).txt |
We take this divided by two and we get 35,000. So we see that in fact, this procedure has a high specific activity. And that makes sense because affinity Chromatography separates these enzymes based on their ability to bind to specific enzymes. And so in our mixture, when we run our mixture proteins along that column of that affinity chromatography setup, only the protein that we want to study will bind to our beads inside that column, the other proteins will essentially go down because enzymes only bind to specific types of proteins. And so that's why this is such a high value, because usually affinity chromatography separates by a very, very large margin. Now, what about the purification level? | Analysis of Protein Purification (Part II).txt |
And so in our mixture, when we run our mixture proteins along that column of that affinity chromatography setup, only the protein that we want to study will bind to our beads inside that column, the other proteins will essentially go down because enzymes only bind to specific types of proteins. And so that's why this is such a high value, because usually affinity chromatography separates by a very, very large margin. Now, what about the purification level? So this divided by this gives us 3500. And what that means is, after all the procedures that we conducted, the final extracted mixture is 3500 times as pure as that initial sample, and that is a high amount. Now, for this set of procedures to actually be good, this yield has to be a high enough yield. | Analysis of Protein Purification (Part II).txt |
So this divided by this gives us 3500. And what that means is, after all the procedures that we conducted, the final extracted mixture is 3500 times as pure as that initial sample, and that is a high amount. Now, for this set of procedures to actually be good, this yield has to be a high enough yield. So let's see what that yield is. So we take 70,000 divided by 200,000. That gives us 70 divided by 200 or 35 divided by 100. | Analysis of Protein Purification (Part II).txt |
So let's see what that yield is. So we take 70,000 divided by 200,000. That gives us 70 divided by 200 or 35 divided by 100. We multiply that ratio by 100 and we get 35%. And this is a high enough yield. So 35% is enough to basically mean we can work with that extracted sample, the protein, to basically study that protein in different ways. | Analysis of Protein Purification (Part II).txt |
We multiply that ratio by 100 and we get 35%. And this is a high enough yield. So 35% is enough to basically mean we can work with that extracted sample, the protein, to basically study that protein in different ways. So these are the five quantities that we have to calculate every time we carry out one of these procedures. And then we also normally expose our extracted portion to SDS page to basically help us visualize if our technique is actually working. And if we combine these two methods, that gives us a very good idea if the purification technique is working. | Analysis of Protein Purification (Part II).txt |
So these are the five quantities that we have to calculate every time we carry out one of these procedures. And then we also normally expose our extracted portion to SDS page to basically help us visualize if our technique is actually working. And if we combine these two methods, that gives us a very good idea if the purification technique is working. So normally, as we go from A to E, the number of bands should decrease. And what that means is we're getting rid of those unwanted proteins and we're focusing in on that protein that we actually want to study. And that is confirmed by these measurements because as we purify the sample, the specific activity has to increase and so should our purification level. | Analysis of Protein Purification (Part II).txt |
So normally, as we go from A to E, the number of bands should decrease. And what that means is we're getting rid of those unwanted proteins and we're focusing in on that protein that we actually want to study. And that is confirmed by these measurements because as we purify the sample, the specific activity has to increase and so should our purification level. And we also have to keep track of the yield. We don't want our yield to drop to a very small amount. For example, if following our procedure, this yield would have been, let's say 5%, then this procedure would not have been efficient because at the end, even though we would have had a high purification value, that yield is not enough. | Analysis of Protein Purification (Part II).txt |
And that's because we want to actually prevent damage to the DNA molecules. And so what we do is in a process known as transcription we synthesize RNA molecules from DNA molecules. And what these RNA molecules are they're copies of specific segments of the DNA molecule and these segments usually contain important genes. So before we can synthesize proteins RNA molecules must be synthesized from DNA molecules in a process known as transcription. And just like the process of DNA replication involves this protein known as DNA polymerase that catalyzes the formation of a phosphodiastor bond in the process of transcription. When we form the RNA from the DNA there is a molecule, a protein known as RNA polymerase that catalyzes the formation of the phosphodia Esther Bond. | RNA Polymerase .txt |
So before we can synthesize proteins RNA molecules must be synthesized from DNA molecules in a process known as transcription. And just like the process of DNA replication involves this protein known as DNA polymerase that catalyzes the formation of a phosphodiastor bond in the process of transcription. When we form the RNA from the DNA there is a molecule, a protein known as RNA polymerase that catalyzes the formation of the phosphodia Esther Bond. So RNA polymerase catalyzes the initiation and the elongation of that RNA polynucleotide chain. And to see what we mean by that, let's take a look at the following diagram. So in the diagram in this chemical equation we basically describe how this reaction takes place and what RNA polymerase does. | RNA Polymerase .txt |
So RNA polymerase catalyzes the initiation and the elongation of that RNA polynucleotide chain. And to see what we mean by that, let's take a look at the following diagram. So in the diagram in this chemical equation we basically describe how this reaction takes place and what RNA polymerase does. So let's suppose we have an RNA chain and we're extending that RNA chain. So we're building our RNA molecule. Now, so far in our RNA molecule we have N number of nucleotides. | RNA Polymerase .txt |
So let's suppose we have an RNA chain and we're extending that RNA chain. So we're building our RNA molecule. Now, so far in our RNA molecule we have N number of nucleotides. And let's suppose we want to add one more nucleotide. We want to add one more ribonucleotide triphosphate. Now, what RNA polymerase does and we'll discuss this in much more detail in just a moment what RNA polymerase does is it essentially attaches the ribonucleocide triphosphate onto the RNA molecule to form an RNA molecule that is extended by one nucleotide. | RNA Polymerase .txt |
And let's suppose we want to add one more nucleotide. We want to add one more ribonucleotide triphosphate. Now, what RNA polymerase does and we'll discuss this in much more detail in just a moment what RNA polymerase does is it essentially attaches the ribonucleocide triphosphate onto the RNA molecule to form an RNA molecule that is extended by one nucleotide. So here we have N number of ribonucleotide triphosphates but here we have N plus one. And in the process we build this phosphodiastor bond between the ribonucleotide triphosphate and the RNA chain and we release a single pyrophosphate molecule. So PP stands for a Pyrophosphate and in fact it's the breakdown of the Pyrophosphate that drives this transcription reaction forward as we'll discuss in much more detail when we'll discuss the process of transcription. | RNA Polymerase .txt |
So here we have N number of ribonucleotide triphosphates but here we have N plus one. And in the process we build this phosphodiastor bond between the ribonucleotide triphosphate and the RNA chain and we release a single pyrophosphate molecule. So PP stands for a Pyrophosphate and in fact it's the breakdown of the Pyrophosphate that drives this transcription reaction forward as we'll discuss in much more detail when we'll discuss the process of transcription. So this is the general equation that describes RNA polymerase. Now, to actually work, what does RNA polymerase actually need? Well, it needs three different things. | RNA Polymerase .txt |
So this is the general equation that describes RNA polymerase. Now, to actually work, what does RNA polymerase actually need? Well, it needs three different things. It basically means the building blocks, the ribonucleotide triphosphates and there are four different types. So we have adenosine five triphosphate we have guanosine five triphosphate we have citadine five prime triphosphate and we have uridine five prime triphosphate. And these building blocks are needed to actually synthesize and elongate that polynucleotide chain. | RNA Polymerase .txt |
It basically means the building blocks, the ribonucleotide triphosphates and there are four different types. So we have adenosine five triphosphate we have guanosine five triphosphate we have citadine five prime triphosphate and we have uridine five prime triphosphate. And these building blocks are needed to actually synthesize and elongate that polynucleotide chain. Now, number two, it actually needs a preexisting DNA template molecule. So usually we're dealing with a double stranded DNA molecule and a double stranded DNA molecule works the best. But in some cases we can also use single stranded DNA molecules as templates. | RNA Polymerase .txt |
Now, number two, it actually needs a preexisting DNA template molecule. So usually we're dealing with a double stranded DNA molecule and a double stranded DNA molecule works the best. But in some cases we can also use single stranded DNA molecules as templates. Now, why do we need a template molecule? Well, we need the DNA template to basically copy that genetic information. And it's the template, that DNA template that is used to basically bring those complementary bases to that elongated polynucleotide chain. | RNA Polymerase .txt |
Now, why do we need a template molecule? Well, we need the DNA template to basically copy that genetic information. And it's the template, that DNA template that is used to basically bring those complementary bases to that elongated polynucleotide chain. So although single stranded DNA molecules work, double stranded DNA molecules are more effective and more common as templates. So RNA polymerase uses this DNA template to basically build a polynucleotide chain that contains complementary bases as we'll see in just a moment. And finally, inside the RNA polymerase molecule at the center there is a pocket that can fit a divalent metal atom. | RNA Polymerase .txt |
So although single stranded DNA molecules work, double stranded DNA molecules are more effective and more common as templates. So RNA polymerase uses this DNA template to basically build a polynucleotide chain that contains complementary bases as we'll see in just a moment. And finally, inside the RNA polymerase molecule at the center there is a pocket that can fit a divalent metal atom. Now, what is a divalent metal atom? Well, it's a metal atom that can gain a positive charge, a charge of positive two. So he can lose two electrons and gain a positive charge of two. | RNA Polymerase .txt |
Now, what is a divalent metal atom? Well, it's a metal atom that can gain a positive charge, a charge of positive two. So he can lose two electrons and gain a positive charge of two. And two types of atoms that work in this particular case are magnesium so, Mg and Manganese MN. And the reason we need this metal atom is because it acts as a cofactor, it increases the efficiency of this enzymes activity. Now let's take a look at the following diagram that basically describes in detail how that bond is formed. | RNA Polymerase .txt |
And two types of atoms that work in this particular case are magnesium so, Mg and Manganese MN. And the reason we need this metal atom is because it acts as a cofactor, it increases the efficiency of this enzymes activity. Now let's take a look at the following diagram that basically describes in detail how that bond is formed. And notice this phosphodiasta bond is formed in a very similar way to how the phosphodiesta bond is formed when DNA polymerase replicates that DNA molecule. So in this particular case, this is our DNA template that the RNA polymerase molecule is actually using. So this is the three end and this is the five end. | RNA Polymerase .txt |
And notice this phosphodiasta bond is formed in a very similar way to how the phosphodiesta bond is formed when DNA polymerase replicates that DNA molecule. So in this particular case, this is our DNA template that the RNA polymerase molecule is actually using. So this is the three end and this is the five end. Now, what our RNA polymerase does is it binds onto that DNA molecule and it reads the DNA template from the three to the five end and that means it builds it from the five to three end. So this is the RNA chain that the RNA polymerase already built. So let's imagine that inside this chain we have N number of nucleotides and this is the N plus one nucleotide that is being added onto that growing RNA chain. | RNA Polymerase .txt |
Now, what our RNA polymerase does is it binds onto that DNA molecule and it reads the DNA template from the three to the five end and that means it builds it from the five to three end. So this is the RNA chain that the RNA polymerase already built. So let's imagine that inside this chain we have N number of nucleotides and this is the N plus one nucleotide that is being added onto that growing RNA chain. So what the RNA polymerase does is it essentially hovers around this section and it brings that complementary ribonucleocide triphosphate which is complementary to this base that is found on the DNA template. Now, how do we know when it's complementary? Well, basically when the bonding is just perfect, this molecule will stay in this location for long enough for this bond to actually take place. | RNA Polymerase .txt |
So what the RNA polymerase does is it essentially hovers around this section and it brings that complementary ribonucleocide triphosphate which is complementary to this base that is found on the DNA template. Now, how do we know when it's complementary? Well, basically when the bonding is just perfect, this molecule will stay in this location for long enough for this bond to actually take place. So it will stay long enough for the bond to form. And the way that the bond forms is so we can label these carbon atoms as carbon atom one, carbon atom two, carbon atom three, carbon atom four, and carbon atom five on this sugar molecule. And we have the three prime hydroxyl group acts as a nucleophile and attacks this innermost phosphorus atom of this incoming nucleuside triphosphate. | RNA Polymerase .txt |
So it will stay long enough for the bond to form. And the way that the bond forms is so we can label these carbon atoms as carbon atom one, carbon atom two, carbon atom three, carbon atom four, and carbon atom five on this sugar molecule. And we have the three prime hydroxyl group acts as a nucleophile and attacks this innermost phosphorus atom of this incoming nucleuside triphosphate. And it forms a covalent bond between the oxygen and this phosphorus. Now eventually this H atom is removed and this Pyrophosphate molecule is kicked off. And so in the process when we form the phosphodieester bond and we form this polynucleotide chain, we essentially release a single pyrophosphate molecule and as we'll see in a future lecture the hydrolysis of the pyrophosphate molecule essentially drives this reaction forward. | RNA Polymerase .txt |
And it forms a covalent bond between the oxygen and this phosphorus. Now eventually this H atom is removed and this Pyrophosphate molecule is kicked off. And so in the process when we form the phosphodieester bond and we form this polynucleotide chain, we essentially release a single pyrophosphate molecule and as we'll see in a future lecture the hydrolysis of the pyrophosphate molecule essentially drives this reaction forward. So RNA polymerase catalyzes the formation of phosphodiasta bond. It brings the complementary nucleotide triphosphate this nucleotide that is complementary to this base into the mixture and then our RNA polymerase holds this in place and it catalyzes the formation of this bond as shown in the following diagram and the pyrophosphate is released as a result. Now, as I mentioned before the RNA polymerase reads the DNA template from the three to five end but it synthesizes that polynucleotide chain in the five to three end and this is the same exact method that DNA polymerase uses. | RNA Polymerase .txt |
So RNA polymerase catalyzes the formation of phosphodiasta bond. It brings the complementary nucleotide triphosphate this nucleotide that is complementary to this base into the mixture and then our RNA polymerase holds this in place and it catalyzes the formation of this bond as shown in the following diagram and the pyrophosphate is released as a result. Now, as I mentioned before the RNA polymerase reads the DNA template from the three to five end but it synthesizes that polynucleotide chain in the five to three end and this is the same exact method that DNA polymerase uses. Remember, DNA polymerase also reads that DNA template from the three to five end and it synthesizes that DNA molecule from the five to three in the same way that RNA polymerase does. Now, the difference between RNA polymerase and DNA polymerase is in RNA polymerase. Notice we do not need a primer sequence to actually initiate the process. | RNA Polymerase .txt |
Remember, DNA polymerase also reads that DNA template from the three to five end and it synthesizes that DNA molecule from the five to three in the same way that RNA polymerase does. Now, the difference between RNA polymerase and DNA polymerase is in RNA polymerase. Notice we do not need a primer sequence to actually initiate the process. So in DNA polymerase we said that DNA polymerase requires that primer sequence but RNA polymerase does not. Now, unlike DNA polymerase which has the endonuclease activity has the ability to essentially correct the mistakes it makes. RNA polymerase cannot correct the mistakes it makes. | RNA Polymerase .txt |
So in DNA polymerase we said that DNA polymerase requires that primer sequence but RNA polymerase does not. Now, unlike DNA polymerase which has the endonuclease activity has the ability to essentially correct the mistakes it makes. RNA polymerase cannot correct the mistakes it makes. So if it incorrectly pairs up two bases it will not be able to correct that mistake. And that means RNA polymerase makes many more mistakes as compared to DNA polymerase which makes less mistakes. So this is the RNA polymerase molecule that essentially is involved in forming that RNA molecule during the process of transcription when we essentially copied the code found in the DNA and form these RNA molecules. | RNA Polymerase .txt |
So if it incorrectly pairs up two bases it will not be able to correct that mistake. And that means RNA polymerase makes many more mistakes as compared to DNA polymerase which makes less mistakes. So this is the RNA polymerase molecule that essentially is involved in forming that RNA molecule during the process of transcription when we essentially copied the code found in the DNA and form these RNA molecules. For example transfer RNA molecules, messenger RNA molecules and ribosomal RNA molecules. Now, the last thing I'd like to mention is in E. Coli cells so in prokaryotic cells, for example, bacterial cells a single RNA polymerase forms all the different types of RNA molecules the mRNA tRNA and RNA. But in our own cells, in the human cells we have three different we have three different RNA polymerases as we'll discuss in a future lecture. | RNA Polymerase .txt |
So two of those carbon atoms basically came from these this acetyl coenzyme A molecule and the other two came from this acetyl coenzyme A molecule. Now, what happens next? Because ultimately we said that fatty acid synthase can generate a 16 carbon fatty acid molecule. So what happens next is is this cycle basically takes place six more times. And when it takes place six more times, it generates a 16 carbon palmitate a 16 carbon palmitate fatty acid molecule. So quickly, let's talk about how that actually takes place. | Fatty Acid Synthesis Part II .txt |
So what happens next is is this cycle basically takes place six more times. And when it takes place six more times, it generates a 16 carbon palmitate a 16 carbon palmitate fatty acid molecule. So quickly, let's talk about how that actually takes place. So in the next step, once we generate this, what will happen is this entire group here, this four carbon group will be moved onto this cysteine in the same way that we move this group onto this holding 16 molecules shown here. So in the next step, we're going to use another Malcolm coenzyme A to attach it onto the ACP that now does not contain this. And now we're going to continue via these steps. | Fatty Acid Synthesis Part II .txt |
So in the next step, once we generate this, what will happen is this entire group here, this four carbon group will be moved onto this cysteine in the same way that we move this group onto this holding 16 molecules shown here. So in the next step, we're going to use another Malcolm coenzyme A to attach it onto the ACP that now does not contain this. And now we're going to continue via these steps. We have a condensation reduction dehydration and a second reduction step. And now we'll generate a six carbon intermediate and this will take place five more times until we generate that 16 carbon palmatoil intermediate molecule. And once we generate that palmatoil intermediate molecule, an enzyme known as Thio esterase will cleave that bond that will release that 16 carbon palmitate fatty acid molecule. | Fatty Acid Synthesis Part II .txt |
We have a condensation reduction dehydration and a second reduction step. And now we'll generate a six carbon intermediate and this will take place five more times until we generate that 16 carbon palmatoil intermediate molecule. And once we generate that palmatoil intermediate molecule, an enzyme known as Thio esterase will cleave that bond that will release that 16 carbon palmitate fatty acid molecule. And that pretty much completes that fatty acid elongation step. So these are the steps involved in synthesizing fatty acid molecules. Again, the first elongation step involves steps one through step seven. | Fatty Acid Synthesis Part II .txt |
We discussed voltage gated on channels and ligand gated on channels. Now, we move on to a slightly different category, vine channels we call gap junctions. Now, gap junctions are also known as cell to cell channels, and we'll see why in just a moment. Now, although gap junctions are in fact on channels, they have very different properties from the properties of voltage gated and ligand gated on channels. And there are five important things that differentiate gap junctions from voltage gated and ligand gated on channels. So let's begin by comparing and contrasting these different types of on channels. | Gap Junctions.txt |
Now, although gap junctions are in fact on channels, they have very different properties from the properties of voltage gated and ligand gated on channels. And there are five important things that differentiate gap junctions from voltage gated and ligand gated on channels. So let's begin by comparing and contrasting these different types of on channels. So voltage gated channels and ligand gated channels are actually closed when that membrane is the rest, and they're only open when that membrane is excited by some type of stimulus. Now, when they do open, they're only open for a very short period of time, about a milliseconds or so, and then they're quickly closed off or they're inactivated. And the size of the pore inside these channels is actually very small. | Gap Junctions.txt |
So voltage gated channels and ligand gated channels are actually closed when that membrane is the rest, and they're only open when that membrane is excited by some type of stimulus. Now, when they do open, they're only open for a very short period of time, about a milliseconds or so, and then they're quickly closed off or they're inactivated. And the size of the pore inside these channels is actually very small. And that's why only small inorganic ions can pass across. And finally, these ion channels are usually very specific to the type of ions they allow across that membrane. Now, what about gap junctions? | Gap Junctions.txt |
And that's why only small inorganic ions can pass across. And finally, these ion channels are usually very specific to the type of ions they allow across that membrane. Now, what about gap junctions? Well, unlike voltage gated and ligand gate on channels, these gap junctions actually have relatively large pore sizes, so the diameter is about 20 angstroms. On top of that, they also allowed the movement of not only inorganic ions, so ions like calcium, sodium, potassium, chloride ions across that particular channel, but they also allow the movement of organic substances such as glucose molecules, amino acids, as well as nucleotides. So we see, unlike the voltage gated and ligangate on channels, which are usually specific and can only move these inorganic ions, gap junctions are non specific. | Gap Junctions.txt |
Well, unlike voltage gated and ligand gate on channels, these gap junctions actually have relatively large pore sizes, so the diameter is about 20 angstroms. On top of that, they also allowed the movement of not only inorganic ions, so ions like calcium, sodium, potassium, chloride ions across that particular channel, but they also allow the movement of organic substances such as glucose molecules, amino acids, as well as nucleotides. So we see, unlike the voltage gated and ligangate on channels, which are usually specific and can only move these inorganic ions, gap junctions are non specific. They allow any molecule to move across or any ion to move across, as long as it's not too large. So large substances such as proteins and polynucleotides and polysaccharides, these molecules cannot pass across gap junctions. Now, unlike these voltage gated and ligand gate on channels, which are only open for about a millisecond before being closed or inactivated, these gap junctions can be open anywhere from seconds to minutes. | Gap Junctions.txt |
They allow any molecule to move across or any ion to move across, as long as it's not too large. So large substances such as proteins and polynucleotides and polysaccharides, these molecules cannot pass across gap junctions. Now, unlike these voltage gated and ligand gate on channels, which are only open for about a millisecond before being closed or inactivated, these gap junctions can be open anywhere from seconds to minutes. Now, voltage gated and ligand gate on channels connect the cytoplasm of a cell to the outside extracellular environment. But we see that these gap junctions actually connect two adjacent cells. And more specific, they transverse the membrane of these two adjacent cells and they connect the cytoplasm of one cell to the cytoplasm of that contiguous adjacent cell. | Gap Junctions.txt |
Now, voltage gated and ligand gate on channels connect the cytoplasm of a cell to the outside extracellular environment. But we see that these gap junctions actually connect two adjacent cells. And more specific, they transverse the membrane of these two adjacent cells and they connect the cytoplasm of one cell to the cytoplasm of that contiguous adjacent cell. So gap junctions transverse two membranes of contiguous cells. That simply means the cells are very close in proximity, closely packed to one another, and they connect the cytoplasm of one cell to the cytoplasm of the adjacent cell. And this can be seen in the following diagram. | Gap Junctions.txt |
So gap junctions transverse two membranes of contiguous cells. That simply means the cells are very close in proximity, closely packed to one another, and they connect the cytoplasm of one cell to the cytoplasm of the adjacent cell. And this can be seen in the following diagram. So this entire structure that transverses the membrane of one cell and the membrane of the adjacent cell, and also transverses this into cellular space. This is a single gap junction. So this is the cytoplasm of one cell and this is the cytoplasm of that adjacent cell. | Gap Junctions.txt |
So this entire structure that transverses the membrane of one cell and the membrane of the adjacent cell, and also transverses this into cellular space. This is a single gap junction. So this is the cytoplasm of one cell and this is the cytoplasm of that adjacent cell. And the length of this gap junction is about 35 angstroms. And the final aspect, the final difference between the voltage gated and ligan gate channels and the gap junctions is that these iron channels are produced by single type of cell, but gap junctions are actually produced by two cells. And we'll see why in just a moment. | Gap Junctions.txt |
And the length of this gap junction is about 35 angstroms. And the final aspect, the final difference between the voltage gated and ligan gate channels and the gap junctions is that these iron channels are produced by single type of cell, but gap junctions are actually produced by two cells. And we'll see why in just a moment. So let's move on to actually discuss what the structure of this gap junction is. So notice we have these two individual structures which are connected end to end inside that intercellular space. So each of these structures is known as a hemichannel or a connection. | Gap Junctions.txt |
So let's move on to actually discuss what the structure of this gap junction is. So notice we have these two individual structures which are connected end to end inside that intercellular space. So each of these structures is known as a hemichannel or a connection. And we see that a single gap junction consists of these two hemichannels, also known as connections that are connected end to end to basically form this single gap junction. Now, if we examine each one of these hemichannels, each one of these hemichannels actually consist of six individual polypeptide chains we call connections. And these connections are basically formed to form a hexamer, which basically means we have six individual units within that hemichannel. | Gap Junctions.txt |
And we see that a single gap junction consists of these two hemichannels, also known as connections that are connected end to end to basically form this single gap junction. Now, if we examine each one of these hemichannels, each one of these hemichannels actually consist of six individual polypeptide chains we call connections. And these connections are basically formed to form a hexamer, which basically means we have six individual units within that hemichannel. Now, cell number one produces hemichannel number one, and cell number two produces hemichannel number two, and then they connect them to form that gap junction. And so that's the final difference between these voltage gated and ligandgate on channels and gap junctions. Now, what exactly? | Gap Junctions.txt |
Now, cell number one produces hemichannel number one, and cell number two produces hemichannel number two, and then they connect them to form that gap junction. And so that's the final difference between these voltage gated and ligandgate on channels and gap junctions. Now, what exactly? Well, actually, before we examine the functionality of these gap junctions, let's discuss how these gap junctions are actually regulated by ourselves. Because just like voltage gated and ligan gate on channels have to be regulated for the proper functionality of the cells, these gap junctions too have to be regulated. And there are four methods by which we can actually close off these gap junctions. | Gap Junctions.txt |
Well, actually, before we examine the functionality of these gap junctions, let's discuss how these gap junctions are actually regulated by ourselves. Because just like voltage gated and ligan gate on channels have to be regulated for the proper functionality of the cells, these gap junctions too have to be regulated. And there are four methods by which we can actually close off these gap junctions. So we can close off these gap junctions by either increasing the concentration of the calcium, increasing the concentration of the h plus ions. So the same thing as saying lowering the PH number three is there are special hormones that can basically induce the process of phosphorylation of these gap junctions. And that too can close off the gap junction. | Gap Junctions.txt |
So we can close off these gap junctions by either increasing the concentration of the calcium, increasing the concentration of the h plus ions. So the same thing as saying lowering the PH number three is there are special hormones that can basically induce the process of phosphorylation of these gap junctions. And that too can close off the gap junction. And number four is in some cases, changing the voltage difference can also actually close off these gap junctions. Now, why would we want to actually close off a gap junction? Well, let's suppose we have two cells which are connected by these gap junctions, and one of the cells is damaged in some way and ends up dying. | Gap Junctions.txt |
And number four is in some cases, changing the voltage difference can also actually close off these gap junctions. Now, why would we want to actually close off a gap junction? Well, let's suppose we have two cells which are connected by these gap junctions, and one of the cells is damaged in some way and ends up dying. So to basically prevent a second nearby healthy cell from being damaged, that dying cell will want to close off these gap junctions. And that's exactly where these different processes come into play to close off that gap junction. Now, finally, let's move on to the functionality of gap junction. | Gap Junctions.txt |
So to basically prevent a second nearby healthy cell from being damaged, that dying cell will want to close off these gap junctions. And that's exactly where these different processes come into play to close off that gap junction. Now, finally, let's move on to the functionality of gap junction. So there are three important functions that we're going to take a look at function number one, intercellular communication. Function number two, cell nourishment. And function number three, embryological development. | Gap Junctions.txt |
So there are three important functions that we're going to take a look at function number one, intercellular communication. Function number two, cell nourishment. And function number three, embryological development. So let's focus on function number one, intercellular communication. This simply means communication between adjacent cells. So let's take a look at example number one. | Gap Junctions.txt |
So let's focus on function number one, intercellular communication. This simply means communication between adjacent cells. So let's take a look at example number one. Let's take a look at our heart. So in our heart, we have these specialized muscle cells we call cardiac myocides, or simply cardiac muscle cells. And these cardiac muscle cells are closely packed, so they are contiguous in nature. | Gap Junctions.txt |
Let's take a look at our heart. So in our heart, we have these specialized muscle cells we call cardiac myocides, or simply cardiac muscle cells. And these cardiac muscle cells are closely packed, so they are contiguous in nature. And because of that, many of these cardiac muscle cells are connected by these gap junctions. So what's the function of these gap junctions? Well, basically, when one cell receives an action potential as a result of these gap junctions, the action potential can actually propagate into nearby cardiac myosytes. | Gap Junctions.txt |
And because of that, many of these cardiac muscle cells are connected by these gap junctions. So what's the function of these gap junctions? Well, basically, when one cell receives an action potential as a result of these gap junctions, the action potential can actually propagate into nearby cardiac myosytes. And what that does is it allows the creation of a continuous and a forceful contraction of the entire heart. And that allows the heart to pump all the blood throughout the cardiovascular system. Now, another example of these intercellular communications via gap junctions is in the muscle cells of the uterus. | Gap Junctions.txt |
And what that does is it allows the creation of a continuous and a forceful contraction of the entire heart. And that allows the heart to pump all the blood throughout the cardiovascular system. Now, another example of these intercellular communications via gap junctions is in the muscle cells of the uterus. So if a woman is about to give birth, so that uterus must contract. And it's these gap junctions that allows the contraction of that uterus muscle. Now, another area that uses gap junctions to basically communicate between nearby cells is inside the brain. | Gap Junctions.txt |
So if a woman is about to give birth, so that uterus must contract. And it's these gap junctions that allows the contraction of that uterus muscle. Now, another area that uses gap junctions to basically communicate between nearby cells is inside the brain. So inside the brain, certain types of nerve cells don't actually use neurotransmitters to send action potential from one cell to another. Instead of using your transmitters, they actually use gap junctions. So on the presynaptic cell and the post synaptic cell, they're connected by these gap junctions. | Gap Junctions.txt |
So inside the brain, certain types of nerve cells don't actually use neurotransmitters to send action potential from one cell to another. Instead of using your transmitters, they actually use gap junctions. So on the presynaptic cell and the post synaptic cell, they're connected by these gap junctions. And that allows the quick movement of the action potential from one cell, the presynaptic neuron, to the other cell that postsynaptic neuron. Now let's move on to function number two, cell nourishment. So every single cell in our body needs things like glucose, amino, amino acids, nucleotides, to actually survive and function correctly. | Gap Junctions.txt |
And that allows the quick movement of the action potential from one cell, the presynaptic neuron, to the other cell that postsynaptic neuron. Now let's move on to function number two, cell nourishment. So every single cell in our body needs things like glucose, amino, amino acids, nucleotides, to actually survive and function correctly. Now, not all of these cells actually are found next to capillaries. And that means not all cells in our body can actually directly obtain the nutrients they need from the body. And that's where these gap, from the capillaries and that's where these gap junctions actually come into play. | Gap Junctions.txt |
Now, not all of these cells actually are found next to capillaries. And that means not all cells in our body can actually directly obtain the nutrients they need from the body. And that's where these gap, from the capillaries and that's where these gap junctions actually come into play. Certain cells which are found far away from capillaries to cells in our bone and cells in our eye, for instance, basically depend on gap junctions to receive the proper nutrients such as glucose and nucleotides and amino acids in order to actually survive and function correctly. And the final function is embryological development. So things like differentiation and setting up the polarity of cells basically depends on the presence of gap junctions. | Gap Junctions.txt |
glycogenesis is the synthesis of glycogen molecules from glucose precursors. So let's suppose we just ingested a meal that is rich in sugar molecules. And so what that means is inside our blood plasma there will be an increase in the glucose levels. Now, our liver is responsible for maintaining the proper glucose levels of our of blood. And so what the liver cells do is they begin to uptake some of that glucose into the cytoplasm of that cell. Now, once the glucose is inside the cell, the liver cell will want to trap that glucose inside the cell and prevent it from actually escaping back into the blood plasma. | Overview of Gluconeogenesis .txt |
Now, our liver is responsible for maintaining the proper glucose levels of our of blood. And so what the liver cells do is they begin to uptake some of that glucose into the cytoplasm of that cell. Now, once the glucose is inside the cell, the liver cell will want to trap that glucose inside the cell and prevent it from actually escaping back into the blood plasma. And so what the liver cells actually do is they phosphorylate the glucose on the 6th position and they use an enzyme known as hexacinase. So hexaginase takes a phosphoryl group from ATP and places it onto carbon six of glucose and that creates glucose six phosphate. Now, once glucose actually once glucose six phosphate is created, glucose phosphate then undergoes a reaction in which there is a transfer of the phosphoryl group from the six position to the first position of that glucose and we form glucose one phosphate. | Overview of Gluconeogenesis .txt |
And so what the liver cells actually do is they phosphorylate the glucose on the 6th position and they use an enzyme known as hexacinase. So hexaginase takes a phosphoryl group from ATP and places it onto carbon six of glucose and that creates glucose six phosphate. Now, once glucose actually once glucose six phosphate is created, glucose phosphate then undergoes a reaction in which there is a transfer of the phosphoryl group from the six position to the first position of that glucose and we form glucose one phosphate. Now, the enzyme that catalyze this step is known as phosphorglucomutase. And what this enzyme does is the following. Inside the active side of this enzyme is a phosphorylated serine residue. | Overview of Gluconeogenesis .txt |
Now, the enzyme that catalyze this step is known as phosphorglucomutase. And what this enzyme does is the following. Inside the active side of this enzyme is a phosphorylated serine residue. And that phosphoryl group on that serene residue is initially placed onto carbon one. And what that generates is an intermediate molecule known as glucose one six bisphosphate. In the second step that is not shown here, this blue phosphoryl group is transferred back onto that Serene residue and that regenerates the catalytic enzyme, the phosphoglucomutase. | Overview of Gluconeogenesis .txt |
And that phosphoryl group on that serene residue is initially placed onto carbon one. And what that generates is an intermediate molecule known as glucose one six bisphosphate. In the second step that is not shown here, this blue phosphoryl group is transferred back onto that Serene residue and that regenerates the catalytic enzyme, the phosphoglucomutase. And it also generates the final product, glucose one phosphate. And so this phosphoryl group that's attached onto carbon one of the glucose ultimately comes from this enzyme and the enzyme picks up this phosphoryl group shown in blue. Now, once we form glucose one phosphate, in the next step, the glucose one phosphate needs to be activated because by itself, glucose one phosphate cannot simply be added onto the growing glycogen chain because it's not active enough. | Overview of Gluconeogenesis .txt |
And it also generates the final product, glucose one phosphate. And so this phosphoryl group that's attached onto carbon one of the glucose ultimately comes from this enzyme and the enzyme picks up this phosphoryl group shown in blue. Now, once we form glucose one phosphate, in the next step, the glucose one phosphate needs to be activated because by itself, glucose one phosphate cannot simply be added onto the growing glycogen chain because it's not active enough. So we have to make it much more reactive and higher in energy. And what we do is we essentially attach a phosphoryl group as well as a uridine molecule onto this section to form the UDP glucose. So that takes place in this step three. | Overview of Gluconeogenesis .txt |
So we have to make it much more reactive and higher in energy. And what we do is we essentially attach a phosphoryl group as well as a uridine molecule onto this section to form the UDP glucose. So that takes place in this step three. So we take the glucose one phosphate shown here and then we basically reacted with a urine triphosphate in the presence of the enzyme known as UDP glucose pyrophosphorylase. And what this enzyme basically does is it attaches the phosphoryl group and the urine onto this region. So we generate the following molecules. | Overview of Gluconeogenesis .txt |
So we take the glucose one phosphate shown here and then we basically reacted with a urine triphosphate in the presence of the enzyme known as UDP glucose pyrophosphorylase. And what this enzyme basically does is it attaches the phosphoryl group and the urine onto this region. So we generate the following molecules. So this entire purple region came from the urine triphosphate and the pyrophosphate, the remaining Pyrophosphate was essentially kicked off. So this is the Pyrophosphate that was kicked off from the urine triphosphate. And the remaining portion of that urine triphosphate basically was attached onto this molecule to form the uriidine diphosphate UDP glucose. | Overview of Gluconeogenesis .txt |
So this entire purple region came from the urine triphosphate and the pyrophosphate, the remaining Pyrophosphate was essentially kicked off. So this is the Pyrophosphate that was kicked off from the urine triphosphate. And the remaining portion of that urine triphosphate basically was attached onto this molecule to form the uriidine diphosphate UDP glucose. Now, the purpose of this was to create this high energy bond that is very reactive because as we'll see in just a moment, this is able to actually undergo the reaction which we attach it onto that growing glycogen chain. Now, the pyrophosphate that is formed in the presence of water, which is basically found in the cytoplasma baristalis, will undergo a hydrolysis reaction in which this bond will be cleaved and will form two orthophosphate molecules. Now, this is the reaction that actually drives the formation of UDP glucose. | Overview of Gluconeogenesis .txt |
Now, the purpose of this was to create this high energy bond that is very reactive because as we'll see in just a moment, this is able to actually undergo the reaction which we attach it onto that growing glycogen chain. Now, the pyrophosphate that is formed in the presence of water, which is basically found in the cytoplasma baristalis, will undergo a hydrolysis reaction in which this bond will be cleaved and will form two orthophosphate molecules. Now, this is the reaction that actually drives the formation of UDP glucose. It's because of this reaction, because this is continually being depleted, that this reaction actually takes place in the product favor direction. So this is an important reaction because it ensures that we continually produce the UDP glucose molecules. Now, once we produce the UDP glucose molecules, the next step is to basically generate a primer molecule. | Overview of Gluconeogenesis .txt |
It's because of this reaction, because this is continually being depleted, that this reaction actually takes place in the product favor direction. So this is an important reaction because it ensures that we continually produce the UDP glucose molecules. Now, once we produce the UDP glucose molecules, the next step is to basically generate a primer molecule. So remember that a primer molecule is basically a short sequence of glucose nucleotides which are connected by alpha one four glycocytic bonds. So why do we need a primer molecule? Because the enzyme that elongates that glycogen chain, known as glycogen synthase, needs a primer to actually initiate that elongation process. | Overview of Gluconeogenesis .txt |
So remember that a primer molecule is basically a short sequence of glucose nucleotides which are connected by alpha one four glycocytic bonds. So why do we need a primer molecule? Because the enzyme that elongates that glycogen chain, known as glycogen synthase, needs a primer to actually initiate that elongation process. It simply cannot begin from scratch. And the enzyme that generates that primer is known as glycogenin. So it is not shown in the diagram, but basically an enzyme known as glycogenin creates this primer. | Overview of Gluconeogenesis .txt |
It simply cannot begin from scratch. And the enzyme that generates that primer is known as glycogenin. So it is not shown in the diagram, but basically an enzyme known as glycogenin creates this primer. And so this is the primer that we have here. So let's say this primer consists of N number of glucose molecules which are all connected by alpha one four glycocitic bonds. So we have not yet created any branching points. | Overview of Gluconeogenesis .txt |
And so this is the primer that we have here. So let's say this primer consists of N number of glucose molecules which are all connected by alpha one four glycocitic bonds. So we have not yet created any branching points. And so this is a linear unbranched polymer. So in the next step, once we generate that primer by using the UDP glucose molecules and the enzyme we call glycogenin. Now, glycogen synthase takes the primer and takes the UDP glucose shown here and basically catalyze the formation of that alpha one four glycocytic bond between this glucose here and the terminal glucose molecule of this primer. | Overview of Gluconeogenesis .txt |
And so this is a linear unbranched polymer. So in the next step, once we generate that primer by using the UDP glucose molecules and the enzyme we call glycogenin. Now, glycogen synthase takes the primer and takes the UDP glucose shown here and basically catalyze the formation of that alpha one four glycocytic bond between this glucose here and the terminal glucose molecule of this primer. And we basically form and extend it. So we extend that primer by one and we also form the UDP, which is basically shown here. So UDP is urine diphosphate, it contains the uridine and two phosphate groups. | Overview of Gluconeogenesis .txt |
And we basically form and extend it. So we extend that primer by one and we also form the UDP, which is basically shown here. So UDP is urine diphosphate, it contains the uridine and two phosphate groups. And we're going to use the UDP in the last step, as we'll see in just a moment. Now, once we form that glycogen, that linear unbranched glycogen, we want to actually begin branching that glycogen. Because remember, branching actually increases the solubility of glycogen within the cytoplasm and it also increases the number of terminal positions on the glycogen. | Overview of Gluconeogenesis .txt |
And we're going to use the UDP in the last step, as we'll see in just a moment. Now, once we form that glycogen, that linear unbranched glycogen, we want to actually begin branching that glycogen. Because remember, branching actually increases the solubility of glycogen within the cytoplasm and it also increases the number of terminal positions on the glycogen. And that in turn increases the rate by which we can break down and synthesize glycogen molecules. So in the next step, step six, we have an enzyme we call the glycogen branching enzyme that basically catalyzes the cleavage of alpha one four glycocitic bond and the formation of Alpha one six glycocitic bond. So let's suppose we have the following hypothetical glycogen molecules. | Overview of Gluconeogenesis .txt |
And that in turn increases the rate by which we can break down and synthesize glycogen molecules. So in the next step, step six, we have an enzyme we call the glycogen branching enzyme that basically catalyzes the cleavage of alpha one four glycocitic bond and the formation of Alpha one six glycocitic bond. So let's suppose we have the following hypothetical glycogen molecules. So let's suppose this molecule here is this molecule that we have right over here. So what the glycogen branching enzyme does is it basically takes a region of seven glucose residues that contain a terminal position shown here. So we have 123-4567. | Overview of Gluconeogenesis .txt |
So let's suppose this molecule here is this molecule that we have right over here. So what the glycogen branching enzyme does is it basically takes a region of seven glucose residues that contain a terminal position shown here. So we have 123-4567. So it cleaves the alpha one four glycocytic bond and then it forms an alpha one six glycocity bond. And so we create this branching point. And notice, as we discussed in a previous lecture, this section has to have at least eleven glucose residues. | Overview of Gluconeogenesis .txt |
So it cleaves the alpha one four glycocytic bond and then it forms an alpha one six glycocity bond. And so we create this branching point. And notice, as we discussed in a previous lecture, this section has to have at least eleven glucose residues. So we have 1234-5678, 910, eleven. So this is how glycogen is actually branched. And once we undergo this entire process, for this process to actually continue taking place, we have to regenerate the UTP molecules, the urine triphosphate that we use up in this particular step, because glycogen will essentially stop taking place if we don't have enough UTP, because we need the UTP to actually generate the UDP glucose, the active form of glucose. | Overview of Gluconeogenesis .txt |
So we have 1234-5678, 910, eleven. So this is how glycogen is actually branched. And once we undergo this entire process, for this process to actually continue taking place, we have to regenerate the UTP molecules, the urine triphosphate that we use up in this particular step, because glycogen will essentially stop taking place if we don't have enough UTP, because we need the UTP to actually generate the UDP glucose, the active form of glucose. And so in the final step, what our cells actually do is they use an ATP molecule, transfer the phosphoral group from ATP onto the UDP that we basically formed in this step here. So we take the UDP, we take an ATP and we transfer that phosphorus loop onto this to basically reform the UTP that now can be used in this step to continually produce the UDP glucose molecules needed to generate that glycogen. And the enzyme that catalyzed this step is nucleocide difosphokinase. | Overview of Gluconeogenesis .txt |
And so in the final step, what our cells actually do is they use an ATP molecule, transfer the phosphoral group from ATP onto the UDP that we basically formed in this step here. So we take the UDP, we take an ATP and we transfer that phosphorus loop onto this to basically reform the UTP that now can be used in this step to continually produce the UDP glucose molecules needed to generate that glycogen. And the enzyme that catalyzed this step is nucleocide difosphokinase. So in this final step, an ATP is used to phosphorylate a UDP and that regenerates that UTP. So once again, let's very briefly overview this entire process. So we ingest a meal that is rich in sugar molecules. | Overview of Gluconeogenesis .txt |
So in this final step, an ATP is used to phosphorylate a UDP and that regenerates that UTP. So once again, let's very briefly overview this entire process. So we ingest a meal that is rich in sugar molecules. The blood level of glucose basically increases. Our liver wants to maintain that and decrease it back to normal. So the liver cells uptake the glucose molecules to trap the glucose within the cell and to prevent it from leaving the cell, they use hexacionase and an ATP to form glucose six phosphate. | Overview of Gluconeogenesis .txt |
The blood level of glucose basically increases. Our liver wants to maintain that and decrease it back to normal. So the liver cells uptake the glucose molecules to trap the glucose within the cell and to prevent it from leaving the cell, they use hexacionase and an ATP to form glucose six phosphate. Next, the glucose six phosphate is transformed into glucose one phosphate by the activity of phosphor glucom Utase. Now, once we form the glucose one phosphate, we want to activate the molecule, make it much more reactive and increase its energy. And so what we do is we use UDP glucose pyrophosphorylase to basically transfer a group from UTP onto the glucose one phosphate and that kicks off a Pyrophosphate, as shown in this diagram. | Overview of Gluconeogenesis .txt |
Next, the glucose six phosphate is transformed into glucose one phosphate by the activity of phosphor glucom Utase. Now, once we form the glucose one phosphate, we want to activate the molecule, make it much more reactive and increase its energy. And so what we do is we use UDP glucose pyrophosphorylase to basically transfer a group from UTP onto the glucose one phosphate and that kicks off a Pyrophosphate, as shown in this diagram. So we generate the UDP glucose and the Pyrophosphate. Now this reaction isn't really product favored. And to make it product favored to drive the formation of UDP glucose, the Pyrophosphate is cleaved by water into two orthophosphate molecules. | Overview of Gluconeogenesis .txt |
So we generate the UDP glucose and the Pyrophosphate. Now this reaction isn't really product favored. And to make it product favored to drive the formation of UDP glucose, the Pyrophosphate is cleaved by water into two orthophosphate molecules. So Pyrophosphate is hydrolyzed into two orthophosphates and this drives the formation of UDP glucose. Now, once we have a bunch of these UDP glucose molecules, the enzyme we call glycogenin, not shown in this diagram, basically uses the UDP glucose molecules to generate a primer, a short sequence of glucose molecules that are linked by alpha one four glycocitic bonds. Because glycogen synthase needs that primer to begin the elongation process, to begin extending that glycogen. | Overview of Gluconeogenesis .txt |
So Pyrophosphate is hydrolyzed into two orthophosphates and this drives the formation of UDP glucose. Now, once we have a bunch of these UDP glucose molecules, the enzyme we call glycogenin, not shown in this diagram, basically uses the UDP glucose molecules to generate a primer, a short sequence of glucose molecules that are linked by alpha one four glycocitic bonds. Because glycogen synthase needs that primer to begin the elongation process, to begin extending that glycogen. So now we take the UDP glucose. In the presence of the primer, the enzyme glycogen synthase basically increases or attaches this glucose onto that primer. In the process, we form a UDP molecule. | Overview of Gluconeogenesis .txt |
So now we take the UDP glucose. In the presence of the primer, the enzyme glycogen synthase basically increases or attaches this glucose onto that primer. In the process, we form a UDP molecule. Now, once we continually add these glucose molecules, eventually we want to actually branch that glycogen. And so that's where step six takes place. Glycogen branching enzyme is responsible for creating those alpha one six linkages which lead to the branching points. | Overview of Gluconeogenesis .txt |
Now, once we continually add these glucose molecules, eventually we want to actually branch that glycogen. And so that's where step six takes place. Glycogen branching enzyme is responsible for creating those alpha one six linkages which lead to the branching points. And for this process to actually continually taking place, we have to take the UDP that we form here and regenerate back that UTP. And that's where step seven comes into play. The enzyme nucleotide di nucleoside diphosphokinase uses an ATP to attach it onto the UDP here, and that forms that UTP. | Overview of Gluconeogenesis .txt |
Well, usually the next process is to take that gene and produce a restriction map for that particular gene. Now what exactly is a restriction map? Well, let's suppose that we have the following ruler and this ruler describes as our gene of interest that we amplify. So this is the double stranded DNA molecule that describes the interest, that describes the gene that we're studying. So what a restriction map is? It's basically a description of all the different locations found on this gene where our restriction enzymes can bind to and cleave that gene. | Restriction Map and Gel Electrophoresis.txt |