Proteopedia - User contributions [en]

2-Oxoglutarate Dehydrogenase

2010-04-23T14:42:27Z

Lucas Evans:

=2-Oxoglutarate Dehydrogenase E1o=

{{STRUCTURE_ 2jgd | PDB= 2jgd | SCENE= }}
__TOC__
==Introduction==
The enzyme 2-Oxoglutarate Dehydrogenase E1o is a subunit the 2-Oxoglutarate Dehydrogenase multi enzyme complex. This subunit is a homo-dimer and one of three enzymes that make up the multi-enzyme complex of 2-Oxoglutarate Dehydrogenase. Each of the <scene name='Lucas_Evans_Sandbox/Monomer/2'>monomers</scene> that make up the homo-dimer have an <scene name='Lucas_Evans_Sandbox/Amp1/1'>adenosine monophosphate</scene> cofactor that facilitates the catalysis. E1o is not categorized in the Structural Classification of Proteins (SCOP); however, the <scene name='Lucas_Evans_Sandbox/Secondary_structure/2'>secondary structure</scene> of one of the dimers shows that this enzyme has large sections of alpha-helices followed by a large sections of parallel beta-pleated sheets these alpha and beta subunits are fused as a single polypeptide <ref name="one">PMID:17367808 </ref>.

==Catalysis==
[[Image:oxoglutarate dehydrogenase.png|thumb|left|The complete reaction of the Oxoglutarate Dehydrogenase Multi-Enzyme Complex]]E1o catalyzes the oxidative decarboxylation of alpha-ketoglutarate to Succinyl-CoA at its <scene name='Lucas_Evans_Sandbox/Active_site/1'>active site</scene> in the fourth step of the metabolic citric acid cycle by acting as a base to facilitate the decarboxylation <ref name="one" />. The main residues responsible for the catalysis are thought to be His 260, Phe 227, Gln685, His 729, Ser302, and His 298 <ref name="one" />. E1o is also thought to have a single active site. E1o also requrires two cofactors in order for it to function properly, Thiamine diphosphate and divalent magnesium ion if either are not present then the enzyme has nearly no activity<ref name="two">PMID:192200 </ref>. The specific mexhanism of the E1o subunit are currently unknown; however, There are several theories as to how it functions, among them is the Hexa Uni Ping Pong theory<ref name="two" />. Even though the mechanism isn't fully know the kinetic data have be calculated and are as follows:
* KM: 0.14 ± 0.04 mM
* Vmax : 9 ± 3 μmol.min-1.mg-1<ref name="three" >PMID:17657817</ref>

==Regulation==
E1o catalyzes a rate limiting step in the Kreb's Cycle and lies far form equilibrium (ΔG= -33kJ/mol). As it is a limiting step this makes it a useful reaction to regulate in order to control the Kreb's Cycle. E1o is inhibited by both NADH and Succinyl-CoA via non competitive feedback inhibition<ref name="one" />.

==Transfer to E2o==
The overall complex (all of the sub units) help catalysis by keeping the necessary substrates for the reaction close within the enzyme so that it is more likely that the substrate will be in favorable conformation. This enzyme is also part of a larger multienzyme complex that channels the intermediates in the catalysis between subunits of the complex thus minimizing unwanted side reactions<ref>Voet, Donald, Judith G. Voet, and Charlotte W. Pratt. Fundamentals of Biochemistry: Life at the Molecular Level. Hoboken, NJ: Wiley, 2008. p.580</ref>. Not only do the subunits ferry products back and forth but each of the mers in the E1o homodimer are connected via a cavity lined with acidic residues thus increasing the dimer's ability to act as a base.

==References==

<references />

2-Oxoglutarate Dehydrogenase

2010-04-23T14:33:05Z

Lucas Evans:

==2-Oxoglutarate Dehydrogenase E1o==

{{STRUCTURE_ 2jgd | PDB= 2jgd | SCENE= }}
==Introduction==
The enzyme 2-Oxoglutarate Dehydrogenase E1o is a subunit the 2-Oxoglutarate Dehydrogenase multi enzyme complex. This subunit is a homo-dimer and one of three enzymes that make up the multi-enzyme complex of 2-Oxoglutarate Dehydrogenase. Each of the <scene name='Lucas_Evans_Sandbox/Monomer/2'>monomers</scene> that make up the homo-dimer have an <scene name='Lucas_Evans_Sandbox/Amp1/1'>adenosine monophosphate</scene> cofactor that facilitates the catalysis. E1o is not categorized in the Structural Classification of Proteins (SCOP); however, the <scene name='Lucas_Evans_Sandbox/Secondary_structure/2'>secondary structure</scene> of one of the dimers shows that this enzyme has large sections of alpha-helices followed by a large sections of parallel beta-pleated sheets these alpha and beta subunits are fused as a single polypeptide <ref name="one">PMID:17367808 </ref>.

==Catalysis==
[[Image:oxoglutarate dehydrogenase.png|thumb|left|The complete reaction of the Oxoglutarate Dehydrogenase Multi-Enzyme Complex]]E1o catalyzes the oxidative decarboxylation of alpha-ketoglutarate to Succinyl-CoA at its <scene name='Lucas_Evans_Sandbox/Active_site/1'>active site</scene> in the fourth step of the metabolic citric acid cycle by acting as a base to facilitate the decarboxylation <ref name="one" />. The main residues responsible for the catalysis are thought to be His 260, Phe 227, Gln685, His 729, Ser302, and His 298 <ref name="one" />. E1o is also thought to have a single active site. E1o also requrires two cofactors in order for it to function properly, Thiamine diphosphate and divalent magnesium ion if either are not present then the enzyme has nearly no activity<ref name="two">PMID:192200 </ref>. The specific mexhanism of the E1o subunit are currently unknown; however, There are several theories as to how it functions, among them is the Hexa Uni Ping Pong theory<ref name="two" />. Even though the mechanism isn't fully know the kinetic data have be calculated and are as follows:
* KM: 0.14 ± 0.04 mM
* Vmax : 9 ± 3 μmol.min-1.mg-1<ref name="three" >PMID:17657817</ref>

==Regulation==
E1o catalyzes a rate limiting step in the Kreb's Cycle and lies far form equilibrium (ΔG= -33kJ/mol). As it is a limiting step this makes it a useful reaction to regulate in order to control the Kreb's Cycle. E1o is inhibited by both NADH and Succinyl-CoA via non competitive feedback inhibition<ref name="one" />.

==Transfer to E2o==
The overall complex (all of the sub units) help catalysis by keeping the necessary substrates for the reaction close within the enzyme so that it is more likely that the substrate will be in favorable conformation. This enzyme is also part of a larger multienzyme complex that channels the intermediates in the catalysis between subunits of the complex thus minimizing unwanted side reactions<ref>Voet, Donald, Judith G. Voet, and Charlotte W. Pratt. Fundamentals of Biochemistry: Life at the Molecular Level. Hoboken, NJ: Wiley, 2008. p.580</ref>. Not only do the subunits ferry products back and forth but each of the mers in the E1o homodimer are connected via a cavity lined with acidic residues thus increasing the dimer's ability to act as a base.

==References==

<references />

File:Oxoglutarate dehydrogenase.png

2010-04-23T14:25:21Z

Lucas Evans:

2-Oxoglutarate Dehydrogenase

2010-04-23T12:05:12Z

Lucas Evans:

==2-Oxoglutarate Dehydrogenase E1o==

{{STRUCTURE_ 2jgd | PDB= 2jgd | SCENE= }}

The enzyme 2-Oxoglutarate Dehydrogenase E1o is a subunit the 2-Oxoglutarate Dehydrogenase multi enzyme complex. This subunit is a homo-dimer and one of three enzymes that make up the multi-enzyme complex of 2-Oxoglutarate Dehydrogenase. Each of the <scene name='Lucas_Evans_Sandbox/Monomer/2'>monomers</scene> that make up the homo-dimer have an <scene name='Lucas_Evans_Sandbox/Amp1/1'>adenosine monophosphate</scene> cofactor that facilitates the catalysis. E1o is not categorized in the Structural Classification of Proteins (SCOP); however, the <scene name='Lucas_Evans_Sandbox/Secondary_structure/2'>secondary structure</scene> of one of the dimers shows that this enzyme has large sections of alpha-helices followed by a large sections of parallel beta-pleated sheets these alpha and beta subunits are fused as a single polypeptide <ref name="one">PMID:17367808 </ref>.

E1o catalyzes the oxidative decarboxylation of alpha-ketoglutarate to Succinyl-CoA at its <scene name='Lucas_Evans_Sandbox/Active_site/1'>active site</scene> in the fourth step of the metabolic citric acid cycle by acting as a base to facilitate the decarboxylation <ref name="one" />. The main residues responsible for the catalysis are thought to be His 260, Phe 227, Gln685, His 729, Ser302, and His 298 <ref name="one" />. E1o is also thought to have a single active site. E1o also requrires two cofactors in order for it to function properly, Thiamine diphosphate and divalent magnesium ion if either are not present then the enzyme has nearly no activity<ref name="two">PMID:192200 </ref>. The specific mexhanism of the E1o subunit are currently unknown; however, There are several theories as to how it functions, among them is the Hexa Uni Ping Pong theory<ref name="two" />

E1o catalyzes a rate limiting step in the Kreb's Cycle and lies far form equilibrium (ΔG= -33kJ/mol). As it is a limiting step this makes it a useful reaction to regulate in order to control the Kreb's Cycle. E1o is inhibited by both NADH and Succinyl-CoA via non competitive feedback inhibition<ref name="one" />.

The overall complex (all of the sub units) help catalysis by keeping the necessary substrates for the reaction close within the enzyme so that it is more likely that the substrate will be in favorable conformation. This enzyme is also part of a larger multienzyme complex that channels the intermediates in the catalysis between subunits of the complex thus minimizing unwanted side reactions<ref>Voet, Donald, Judith G. Voet, and Charlotte W. Pratt. Fundamentals of Biochemistry: Life at the Molecular Level. Hoboken, NJ: Wiley, 2008. p.580</ref>. Not only do the subunits ferry products back and forth but each of the mers in the E1o homodimer are connected via a cavity lined with acidic residues thus increasing the dimer's ability to act as a base.

==References==

<references />

2-Oxoglutarate Dehydrogenase

2010-04-23T12:04:04Z

Lucas Evans:

2-Oxoglutarate Dehydrogenase

2010-04-23T12:02:22Z

Lucas Evans:

2-Oxoglutarate Dehydrogenase

2010-04-23T11:58:53Z

Lucas Evans:

==2-Oxoglutarate Dehydrogenase E1o==

{{STRUCTURE_ 2jgd | PDB= 2jgd | SCENE= }}

The enzyme 2-Oxoglutarate Dehydrogenase E1o is a subunit the 2-Oxoglutarate Dehydrogenase multi enzyme complex. This subunit is a homo-dimer and one of three enzymes that make up the multi-enzyme complex of 2-Oxoglutarate Dehydrogenase. Each of the <scene name='Lucas_Evans_Sandbox/Monomer/2'>monomers</scene> that make up the homo-dimer have an <scene name='Lucas_Evans_Sandbox/Amp1/1'>adenosine monophosphate</scene> cofactor that facilitates the catalysis. E1o is not categorized in the Structural Classification of Proteins (SCOP); however, the <scene name='Lucas_Evans_Sandbox/Secondary_structure/2'>secondary structure</scene> of one of the dimers shows that this enzyme has large sections of alpha-helices followed by a large sections of parallel beta-pleated sheets these alpha and beta subunits are fused as a single polypeptide <ref name="one">PMID:17367808 </ref>.

E1o catalyzes the oxidative decarboxylation of alpha-ketoglutarate to Succinyl-CoA at its <scene name='Lucas_Evans_Sandbox/Active_site/1'>active site</scene> in the fourth step of the metabolic citric acid cycle by acting as a base to facilitate the decarboxylation <ref name="one" />. The main residues responsible for the catalysis are thought to be His 260, Phe 227, Gln685, His 729, Ser302, and His 298 <ref name="one" />. E1o is also thought to have a single active site. E1o also requrires two cofactors in order for it to function properly, Thiamine diphosphate and divalent magnesium ion if either are not present then the enzyme has nearly no activity<ref name="two">PMID:1164543 </ref>. The specific mexhanism of the E1o subunit are currently unknown; however, There are several theories as to how it functions, among them is the Hexa Uni Ping Pong theory<ref name="two" />

E1o catalyzes a rate limiting step in the Kreb's Cycle and lies far form equilibrium (ΔG= -33kJ/mol). As it is a limiting step this makes it a useful reaction to regulate in order to control the Kreb's Cycle. E1o is inhibited by both NADH and Succinyl-CoA via non competitive feedback inhibition<ref name="one" />.

The overall complex (all of the sub units) help catalysis by keeping the necessary substrates for the reaction close within the enzyme so that it is more likely that the substrate will be in favorable conformation. This enzyme is also part of a larger multienzyme complex that channels the intermediates in the catalysis between subunits of the complex thus minimizing unwanted side reactions<ref>Voet, Donald, Judith G. Voet, and Charlotte W. Pratt. Fundamentals of Biochemistry: Life at the Molecular Level. Hoboken, NJ: Wiley, 2008. p.580</ref>. Not only do the subunits ferry products back and forth but each of the mers in the E1o homodimer are connected via a cavity lined with acidic residues thus increasing the dimer's ability to act as a base.

==References==

<references />

2-Oxoglutarate Dehydrogenase

2010-03-31T23:17:47Z

Lucas Evans: /* 2-Oxoglutarate Dehydrogenase E1o */

==2-Oxoglutarate Dehydrogenase E1o==

{{STRUCTURE_ 2jgd | PDB= 2jgd | SCENE= }}

The enzyme 2-Oxoglutarate Dehydrogenase E1o is a subunit the 2-Oxoglutarate Dehydrogenase multi enzyme complex. This subunit is a homo-dimer and one of three enzymes that make up the multi-enzyme complex of 2-Oxoglutarate Dehydrogenase. Each of the <scene name='Lucas_Evans_Sandbox/Monomer/2'>monomers</scene> that make up the homo-dimer have an <scene name='Lucas_Evans_Sandbox/Amp1/1'>adenosine monophosphate</scene> cofactor that facilitates the catalysis. E1o is not categorized in the Structural Classification of Proteins (SCOP); however, the <scene name='Lucas_Evans_Sandbox/Secondary_structure/2'>secondary structure</scene> of one of the dimers shows that this enzyme has large sections of alpha-helices followed by a large sections of parallel beta-pleated sheets these alpha and beta subunits are fused as a single polypeptide <ref name="one">PMID:17367808 </ref>.

E1o catalyzes the oxidative decarboxylation of alpha-ketoglutarate at its <scene name='Lucas_Evans_Sandbox/Active_site/1'>active site</scene> in the metabolic citric acid cycle by acting as a base to facilitate the decarboxylation <ref name="one" />. The main residues responsible for the catalysis are thought to be His 260, Phe 227, Gln685, His 729, Ser302, and His 298 <ref name="one" />. The overall complex (all of the sub units) help catalysis by keeping the necessary substrates for the reaction close within the enzyme so that it is more likely that the substrate will be in favorable conformation. This enzyme is also part of a larger multienzyme complex that channels the intermediates in the catalysis between subunits of the complex thus minimizing unwanted side reactions<ref>Voet, Donald, Judith G. Voet, and Charlotte W. Pratt. Fundamentals of Biochemistry: Life at the Molecular Level. Hoboken, NJ: Wiley, 2008. p.580</ref>. Not only do the subunits ferry products back and forth but each of the mers in the E1o homodimer are connected via a cavity lined with acidic residues thus increasing the dimer's ability to act as a base.

==References==

<references />

2-Oxoglutarate Dehydrogenase

2010-03-31T23:01:45Z

Lucas Evans: /* 2-Oxoglutarate Dehydrogenase E1o */

==2-Oxoglutarate Dehydrogenase E1o==

{{STRUCTURE_ 2jgd | PDB= 2jgd | SCENE= }}
2-Oxoglutarate Dehydrogenase E1o is part of the 2-Oxoglutarate Dehydrogenase multi enzyme complex. E1o catalyzes the oxidative decarboxylation of alpha-ketoglutarate at its
<scene name='Lucas_Evans_Sandbox/Active_site/1'>active site</scene> in the metabolic citric acid cycle. This subunit is a homo-dimer and one of three enzymes that make up the multi-enzyme complex of 2-Oxoglutarate Dehydrogenase. Each of the <scene name='Lucas_Evans_Sandbox/Monomer/2'>monomers</scene> that make up the homo-dimer have an <scene name='Lucas_Evans_Sandbox/Amp1/1'>adenosine monophosphate</scene> cofactor that facilitates the catalysis. E1o is not categorized in the Structural Classification of Proteins (SCOP); however, the <scene name='Lucas_Evans_Sandbox/Secondary_structure/2'>secondary structure</scene> of one of the dimers shows that this enzyme has large sections of alpha-helices followed by a large section of parallel beta-pleated sheets these alpha and beta subunits are fused as a single polypeptide <ref>PMID:17367808 </ref>. The main residues responsible for the catalysis are thought to be His 260, Phe 227, Gln685, His 729, Ser302, and His 298 <ref>PMID:17367808 </ref>. This enzyme catalyzes the oxidative decarboxylation by acting as a base to facilitate the decarboxylation <ref>PMID:17367808 </ref>. The overall enzyme (all of the sub units) help catalysis by keeping the necessary substrates for the reaction close within the enzyme so that it is more likely that the substrate will be in a conformation that will allow it to react. This enzyme is also part of a larger multienzyme complex that channels the intermediates in the catalysis between subunits of the complex thus minimizing unwanted side reactions<ref>Voet, Donald, Judith G. Voet, and Charlotte W. Pratt. Fundamentals of Biochemistry: Life at the Molecular Level. Hoboken, NJ: Wiley, 2008. </ref>. Not only do the subunits ferry products back and forth but each of the mers in the E1o homodimer are connected via a cavity lined with acidic residues thus increasing the dimer's ability to act as a base.

==References==

<references />

2-Oxoglutarate Dehydrogenase

2010-03-01T22:52:42Z

Lucas Evans: /* 2-Oxoglutarate Dehydrogenase E1o */

==2-Oxoglutarate Dehydrogenase E1o==

{{STRUCTURE_ 2jgd | PDB= 2jgd | SCENE= }}
2-Oxoglutarate Dehydrogenase E1o is part of the 2-Oxoglutarate Dehydrogenase multi enzyme complex. E1o catalyzes the oxidative decarboxylation of alpha-ketoglutarate at its
<scene name='Lucas_Evans_Sandbox/Active_site/1'>active site</scene> in the metabolic citric acid cycle. This subunit is a homo-dimer and one of three enzymes that make up the multi-enzyme complex of 2-Oxoglutarate Dehydrogenase. Each of the <scene name='Lucas_Evans_Sandbox/Monomer/2'>monomers</scene> that make up the homo-dimer have an <scene name='Lucas_Evans_Sandbox/Amp1/1'>adenosine monophosphate</scene> cofactor that facilitates the catalysis. This enzyme catalyzes the oxidative decarboxylation by keeping the necessary substrates for the reaction close within the enzyme so that it is more likely that the substrate will be in a conformation that will allow it to react. This enzyme is also part of a larger multienzyme complex that chanells the intermediates in the catalysis between subunits of the complex thus minimizing unwanted side reactions<ref>Voet, Donald, Judith G. Voet, and Charlotte W. Pratt. Fundamentals of Biochemistry: Life at the Molecular Level. Hoboken, NJ: Wiley, 2008. </ref>. E1o is not categorized in the Structural Classification of Proteins (SCOP); however, the <scene name='Lucas_Evans_Sandbox/Secondary_structure/2'>secondary structure</scene> of one of the dimers shows that this enzyme has large sections of alpha-helices followed by a large section of parallel beta-pleated sheets these alpha and beta subunits are fused as a single polypeptide <ref>PMID:17367808</ref>.

==References==

<references />

2-Oxoglutarate Dehydrogenase

2010-03-01T22:43:29Z

Lucas Evans: /* 2-Oxoglutarate Dehydrogenase E1o */

==2-Oxoglutarate Dehydrogenase E1o==

{{STRUCTURE_ 2jgd | PDB= 2jgd | SCENE= }}
2-Oxoglutarate Dehydrogenase E1o is part of the 2-Oxoglutarate Dehydrogenase multi enzyme complex. E1o catalyzes the that catalyzes the the oxidative decarboxylation of alpha-ketoglutarate at its
<scene name='Lucas_Evans_Sandbox/Active_site/1'>active site</scene><ref>Voet, Donald, Judith G. Voet, and Charlotte W. Pratt. Fundamentals of Biochemistry: Life at the Molecular Level. Hoboken, NJ: Wiley, 2008. </ref>. This subunit is a homo-dimer and one of three enzymes that make up the multi-enzyme complex of 2-Oxoglutarate Dehydrogenase. each of the <scene name='Lucas_Evans_Sandbox/Monomer/1'>monomers</scene> that make up the homo-dimer has an <scene name='Lucas_Evans_Sandbox/Amp1/1'>Adenosine Monophosphate</scene> cofactor that facilitates the catalysis. This enzyme is involved in the metabolic citric acid cycle. E1o is not categorized in the Structural Classification of Proteins (SCOP); hoevever, the <scene name='Lucas_Evans_Sandbox/Secondary_structure/2'>secondary structure</scene> of one of the dimers shows that this enzyme has large sections of alpha-helices followed by a large section of parallel beta-pleated sheets these alpha and beta subunits are fused as a single polypeptide <ref>PMID:17367808</ref>. This enzyme catalyzes the oxidative decarboxylation by keeping the necessary substrates for the reaction close within the enzyme so that it is more likely that the substrate will be in a conformation that will alow it to react. The exzyme also is part of a larger multienzyme complex that chanells the intermediates in the catalysis between subunits of the complex thus minimizing other reactions.
==References==

<references />

2-Oxoglutarate Dehydrogenase

2010-03-01T22:01:17Z

Lucas Evans: /* This is a placeholder */

==2-Oxoglutarate Dehydrogenase E1o==

{{STRUCTURE_ 2jgd | PDB= 2jgd | SCENE= }}
2-Oxoglutarate Dehydrogenase E1o is part of the 2-Oxoglutarate Dehydrogenase multi enzyme complex. E1o catalyzes the that catalyzes the the decarboxylation of R-C-OH complexed with thiamine diphosphate to R-C=O. This subunit is a homo-dimer and one of three enzymes that make up the multi-enzyme complex of 2-Oxoglutarate Dehydrogenase. each of the monomers that make up the homo-dimer has an <scene name='Lucas_Evans_Sandbox/Amp1/1'>Adenosine Monophosphate</scene> cofactor that facilitates the catalysis. This subunit is involved in the metabolic citric acid cycle. E1o is not categorized in the Structural Classification of Proteins (SCOP); hoevever, the <scene name='Lucas_Evans_Sandbox/Secondary_structure/1'>secondary structure</scene> of one of the dimers shows that this enzyme has large sections of alpha-helices followed by a small section of parallel beta-pleated sheets.

2-Oxoglutarate Dehydrogenase

2010-03-01T19:48:04Z

Lucas Evans: /* This is a placeholder */

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{{STRUCTURE_ 2jgd | PDB= 2jgd | SCENE= }}

2-Oxoglutarate Dehydrogenase

2010-03-01T19:47:32Z

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2-Oxoglutarate Dehydrogenase

2010-03-01T02:23:07Z

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2-Oxoglutarate Dehydrogenase

2010-03-01T02:21:11Z

Lucas Evans: New page: ==This is a placeholder== This is a placeholder text to help you get started in placing a Jmol applet on your page. At any time, click "Show Preview" at the bottom of this page to see how...