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https://proteopedia.org/api.php?action=feedcontributions&feedformat=atom&user=Max+Lein Proteopedia - User contributions [en] 2026-09-15T21:56:07Z User contributions MediaWiki 1.43.8 https://proteopedia.org/index.php?title=User:Max_Lein/Sandbox&diff=804584 User:Max Lein/Sandbox 2008-12-02T12:46:26Z

<p>Max Lein: </p> <hr /> <div>[[Image:1gpa.png|left|200px]]<br /> <br /> <br /> {{STRUCTURE_1gpa| PDB=1gpa | SCENE= }} <br /> <br /> ==About this Structure==<br /> The PDB 1gpa contains 4 chains of the 'A' form of glycogen phosphorylase. Each subunit contains a phosphate group bound to Ser14, sulfate groups bound to two effector sites (sulfate acts as a mimic of phosphate groups), and the cofactor pyridoxal-5'-phosphate bound to K681. See the links section at the end of this page for links to more structural information on glycogen phosphorylase.<br /> <br /> ==Reaction==<br /> Glycogen phosphorylase (GP) catalyzes the degradation of the reducing end of glycogen into glucose-1-phosphate. It employs a cofactor called pyridoxal-5’ –phosphate, that is located in the active site and bound to a K681 residue with a Schiff base linkage. PLP shuttles the phosphate group onto the substrate.<br /> <br /> ==History==<br /> This protein comes from the muscle tissue of [http://en.wikipedia.org/wiki/Oryctolagus_cuniculus Oryctolagus cuniculus]. There is an isozyme from liver tissue that is regulated by glucagon instead of epinephrine, with a different gene that encodes it and different regulation properties.<br /> <br /> Glycogen phosphorylase was the first phosphorylase enzyme to be discovered, and the first example of regulation via covalent modification. <br /> <br /> In the 1930s, the first work done by Carl and Gerty Cori. They proved that the enzyme exists in 'A' and 'B' forms, and they showed that the reverse reaction produced glycogen. They won the Nobel Prize in 1947 along with Bernardo Housay of Argentina for their work on carbohydrate metabolism. This was also the first example of a polymerizing enzyme, inspiring others to look for other polymerizing enzymes.<br /> <br /> Subsequently, Earl Sutherland found that the 'B' form predominates in resting muscle and epinephrine triggers activation to form 'A'. Since then, many groups have worked on this enzyme, both to understand its mechanism and to discover drug targets. Crystal structures have been obtained for the protein in the 'A' and 'B' form, in the presence of natural substrates, inhibitors, and transition state analogs. Please see the end of this article for links to crystallographic information.<br /> <br /> ==Activity and Regulation of GP==<br /> In its active form, GP is a dimer of two identical subunits. The subunits make interactions that stabilize the final structure.<br /> <br /> Each Sub-unit contains 5 potential effector sites:<br /> 1. Ser14 phosphate-recognition site.<br /> 2. AMP activation / Glc-6-P inhibition site.<br /> 3. Catalytic site that binds glycogen, Glc-1-P<br /> 4. Inhibitor site, 12Å from catalytic site, binds caffeine and related compounds.<br /> 5. Glycogen storage site.<br /> <br /> There are two forms of the enzyme, designated as 'A' and 'B', that are controlled hormonally. The 'B' form is converted into the 'A' form by phosphorylase kinase, which catalyzes the addition of phosphate from ATP to Ser14 near the N-terminus. This represents the final step in a signal transduction cascade in response to the hormone epinephrine, associated with the 'fight-or-flight' response and causing an increase in available energy to the organism as a whole. The N-terminus contains a high percentage of basic residues, which interact favorably with a pocket of acidic residues (Asp109, Glu110, Glu120, Glu501, Glu505 and Glu509) in the 'B' form. Once Ser14 is phosphorylated, the N-terminus is forced ~50Å away from the acidic residues, settling into a region with R69 and R45' (prime denotes a residue from the adjacent subunit). In summary, the conformatino change causes an ordering of the N-terminal chain and a disordering of residues at the C-terminal. Once disordered, the C-terminal residues are no longer able to block substrate entry into the active site. The enzyme phosphatase is able to remove the phosphate and return GP to form 'B'.<br /> <br /> In addition, the 'A' and 'B' forms can be regulated futher by small molecules in the cell. This allows individual cells to ignore the hormonal signal if they already have enough available energy (at high concentrations of glucose derivatives or ATP, designated as the 'T' state for low substrate affinity), or activate GP without a hormonal signal when energy for the individual cell is needed (high concentrations of AMP, designated as the 'R' state for high substrate affinity). <br /> <br /> ==Links==<br /> <br /> 1GPA is a [[Single protein]] structure of sequence from [http://en.wikipedia.org/wiki/Oryctolagus_cuniculus Oryctolagus cuniculus]. Additional information on 1GPA is available in a page on [http://pdb.rcsb.org/pdb/static.do?p=education_discussion/molecule_of_the_month/pdb24_1.html Glycogen Phosphorylase] at the RCSB PDB [http://pdb.rcsb.org/pdb/static.do?p=education_discussion/molecule_of_the_month/index.html Molecule of the Month]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1GPA OCA]. <br /> <br /> ==References==<br /> Structural mechanism for glycogen phosphorylase control by phosphorylation and AMP., Barford D, Hu SH, Johnson LN, J Mol Biol. 1991 Mar 5;218(1):233-60. PMID:[http://www.ncbi.nlm.nih.gov/pubmed/1900534 1900534]<br /> <br /> A New Allosteric site in Glycogen Phoshporylase b as a Target for Drug Interactions., Barford D, Hu SH, Johnson LN Structure. 2000. Vol. 8, No. 6, pp. 575-584.<br /> <br /> Electrostatic Effects in the Control of Glycogen Phosphorylase by Phosphorylation., Barford D., Johnson LN. Prot. Sci. 1994. Vol. 8, pp. 1726-1730.<br /> [[Category: Glycogen Phosphorylase]]<br /> [[Category: Oryctolagus cuniculus]]<br /> [[Category: Phosphorylase]]<br /> [[Category: Single protein]]<br /> [[Category: Barford, D.]]<br /> [[Category: Hu, S H.]]<br /> [[Category: Johnson, L N.]]<br /> [[Category: Glycogen phosphorylase]]<br /> <br /> ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Wed Jul 23 10:43:26 2008''</div>

Max Lein https://proteopedia.org/index.php?title=User:Max_Lein/Sandbox&diff=804583 User:Max Lein/Sandbox 2008-12-02T10:16:16Z

<p>Max Lein: </p> <hr /> <div>{{Seed}}<br /> [[Image:1gpa.png|left|200px]]<br /> <br /> <br /> {{STRUCTURE_1gpa| PDB=1gpa | SCENE= }} <br /> <br /> ==About this Structure==<br /> The PDB 1gpa contains 4 chains of the 'A' form of glycogen phosphorylase. Each subunit contains a phosphate group bound to Ser14, sulfate groups bound to two effector sites (sulfate acts as a mimic of phosphate groups), and the cofactor pyridoxal-5'-phosphate bound to K681. See the links section at the end of this page for links to more structural information on glycogen phosphorylase.<br /> <br /> ==Reaction==<br /> Glycogen phosphorylase (GP) catalyzes the degradation of the reducing end of glycogen into glucose-1-phosphate. It employs a cofactor called pyridoxal-5’ –phosphate, that is located in the active site and bound to a K681 residue with a Schiff base linkage. PLP shuttles the phosphate group onto the substrate.<br /> <br /> ==History==<br /> This protein comes from the muscle tissue of [http://en.wikipedia.org/wiki/Oryctolagus_cuniculus Oryctolagus cuniculus]. There is an isozyme from liver tissue that is regulated by glucagon instead of epinephrine, with a different gene that encodes it and different regulation properties.<br /> <br /> Glycogen phosphorylase was the first phosphorylase enzyme to be discovered, and the first example of regulation via covalent modification. <br /> <br /> In the 1930s, the first work done by Carl and Gerty Cori. They proved that the enzyme exists in 'A' and 'B' forms, and they showed that the reverse reaction produced glycogen. They won the Nobel Prize in 1947 along with Bernardo Housay of Argentina for their work on carbohydrate metabolism. This was also the first example of a polymerizing enzyme, inspiring others to look for other polymerizing enzymes.<br /> <br /> Subsequently, Earl Sutherland found that the 'B' form predominates in resting muscle and epinephrine triggers activation to form 'A'. Since then, many groups have worked on this enzyme, both to understand its mechanism and to discover drug targets. Crystal structures have been obtained for the protein in the 'A' and 'B' form, in the presence of natural substrates, inhibitors, and transition state analogs. Please see the end of this article for links to crystallographic information.<br /> <br /> ==Activity and Regulation of GP==<br /> In its active form, GP is a dimer of two identical subunits. The subunits make interactions that stabilize the final structure.<br /> <br /> Each Sub-unit contains 5 potential effector sites:<br /> 1. Ser14 phosphate-recognition site.<br /> 2. AMP activation / Glc-6-P inhibition site.<br /> 3. Catalytic site that binds glycogen, Glc-1-P<br /> 4. Inhibitor site, 12Å from catalytic site, binds caffeine and related compounds.<br /> 5. Glycogen storage site.<br /> <br /> There are two forms of the enzyme, designated as 'A' and 'B', that are controlled hormonally. The 'B' form is converted into the 'A' form by phosphorylase kinase, which catalyzes the addition of phosphate from ATP to Ser14 near the N-terminus. This represents the final step in a signal transduction cascade in response to the hormone epinephrine, associated with the 'fight-or-flight' response and causing an increase in available energy to the organism as a whole. The N-terminus contains a high percentage of basic residues, which interact favorably with a pocket of acidic residues (Asp109, Glu110, Glu120, Glu501, Glu505 and Glu509) in the 'B' form. Once Ser14 is phosphorylated, the N-terminus is forced ~50Å away from the acidic residues, settling into a region with R69 and R45' (prime denotes a residue from the adjacent subunit). In summary, the conformatino change causes an ordering of the N-terminal chain and a disordering of residues at the C-terminal. Once disordered, the C-terminal residues are no longer able to block substrate entry into the active site. The enzyme phosphatase is able to remove the phosphate and return GP to form 'B'.<br /> <br /> In addition, the 'A' and 'B' forms can be regulated futher by small molecules in the cell. This allows individual cells to ignore the hormonal signal if they already have enough available energy (at high concentrations of glucose derivatives or ATP, designated as the 'T' state for low substrate affinity), or activate GP without a hormonal signal when energy for the individual cell is needed (high concentrations of AMP, designated as the 'R' state for high substrate affinity). <br /> <br /> ==Links==<br /> <br /> 1GPA is a [[Single protein]] structure of sequence from [http://en.wikipedia.org/wiki/Oryctolagus_cuniculus Oryctolagus cuniculus]. Additional information on 1GPA is available in a page on [http://pdb.rcsb.org/pdb/static.do?p=education_discussion/molecule_of_the_month/pdb24_1.html Glycogen Phosphorylase] at the RCSB PDB [http://pdb.rcsb.org/pdb/static.do?p=education_discussion/molecule_of_the_month/index.html Molecule of the Month]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1GPA OCA]. <br /> <br /> ==References==<br /> Structural mechanism for glycogen phosphorylase control by phosphorylation and AMP., Barford D, Hu SH, Johnson LN, J Mol Biol. 1991 Mar 5;218(1):233-60. PMID:[http://www.ncbi.nlm.nih.gov/pubmed/1900534 1900534]<br /> <br /> A New Allosteric site in Glycogen Phoshporylase b as a Target for Drug Interactions., Barford D, Hu SH, Johnson LN Structure. 2000. Vol. 8, No. 6, pp. 575-584.<br /> <br /> Electrostatic Effects in the Control of Glycogen Phosphorylase by Phosphorylation., Barford D., Johnson LN. Prot. Sci. 1994. Vol. 8, pp. 1726-1730.<br /> [[Category: Glycogen Phosphorylase]]<br /> [[Category: Oryctolagus cuniculus]]<br /> [[Category: Phosphorylase]]<br /> [[Category: Single protein]]<br /> [[Category: Barford, D.]]<br /> [[Category: Hu, S H.]]<br /> [[Category: Johnson, L N.]]<br /> [[Category: Glycogen phosphorylase]]<br /> <br /> ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Wed Jul 23 10:43:26 2008''</div>

Max Lein https://proteopedia.org/index.php?title=User:Max_Lein/Sandbox&diff=804582 User:Max Lein/Sandbox 2008-12-02T09:22:08Z

<p>Max Lein: </p> <hr /> <div>{{Seed}}<br /> [[Image:1gpa.png|left|200px]]<br /> <br /> <br /> {{STRUCTURE_1gpa| PDB=1gpa | SCENE= }} <br /> <br /> ==About this Structure==<br /> The PDB 1gpa contains 4 chains of the 'A' form of glycogen phosphorylase. Each subunit contains a phosphate group bound to Ser14, sulfate groups bound to two effector sites (sulfate acts as a mimic of phosphate groups), and the cofactor pyridoxal-5'-phosphate bound to K681. See the links section at the end of this page for links to more structural information on glycogen phosphorylase.<br /> <br /> ==Reaction==<br /> Glycogen phosphorylase (GP) catalyzes the degradation of the reducing end of glycogen into glucose-1-phosphate. It employs a cofactor called pyridoxal-5’ –phosphate, that is located in the active site and bound to a K681 residue with a Schiff base linkage. PLP shuttles the phosphate group onto the substrate.<br /> <br /> ==History==<br /> This protein comes from the muscle tissue of [http://en.wikipedia.org/wiki/Oryctolagus_cuniculus Oryctolagus cuniculus]. There is an isozyme from liver tissue that is regulated by glucagon instead of epinephrine, with a different gene that encodes it and different regulation properties.<br /> <br /> Glycogen phosphorylase was the first phosphorylase enzyme to be discovered, and the first example of regulation via covalent modification. <br /> <br /> In the 1930s, the first work done by Carl and Gerty Cori. They proved that the enzyme exists in 'A' and 'B' forms, and they showed that the reverse reaction produced glycogen. They won the Nobel Prize in 1947 along with Bernardo Housay of Argentina for their work on carbohydrate metabolism. This was also the first example of a polymerizing enzyme, inspiring others to look for other polymerizing enzymes.<br /> <br /> Subsequently, Earl Sutherland found that the 'B' form predominates in resting muscle and epinephrine triggers activation to form 'A'. Since then, many groups have worked on this enzyme, both to understand its mechanism and to discover drug targets. Crystal structures have been obtained for the protein in the 'A' and 'B' form, in the presence of natural substrates, inhibitors, and transition state analogs. Please see the end of this article for links to crystallographic information.<br /> <br /> ==Activity and Regulation of GP==<br /> In its active form, GP is a dimer of two identical subunits. The subunits make interactions that stabilize the final structure.<br /> <br /> Each Sub-unit contains 5 potential effector sites:<br /> 1. Ser14 phosphate-recognition site.<br /> 2. AMP activation / Glc-6-P inhibition site.<br /> 3. Catalytic site that binds glycogen, Glc-1-P<br /> 4. Inhibitor site, 12Å from catalytic site, binds caffeine and related compounds.<br /> 5. Glycogen storage site.<br /> <br /> There are two forms of the enzyme, designated as 'A' and 'B', that are controlled hormonally. The 'B' form is converted into the 'A' form by phosphorylase kinase, which catalyzes the addition of phosphate from ATP to Ser14 near the N-terminus. This represents the final step in a signal transduction cascade in response to the hormone epinephrine, associated with the 'fight-or-flight' response and causing an increase in available energy to the organism as a whole. The N-terminus contains a high percentage of basic residues, which interact favorably with a pocket of acidic residues in the 'B' form. Once Ser14 is phosphorylated, the N-terminus is forced ~50Å away from the acidic residues, settling into a region with R69 and R45' (prime denotes a residue from the adjacent subunit). The enzyme phosphatase is able to remove the phosphate and return GP to form 'B'.<br /> <br /> In addition, the 'A' and 'B' forms can be regulated futher by small molecules in the cell. This allows individual cells to ignore the hormonal signal if they already have enough available energy (at high concentrations of glucose derivatives or ATP, designated as the 'T' state for low substrate affinity), or activate GP without a hormonal signal when energy for the individual cell is needed (high concentrations of AMP, designated as the 'R' state for high substrate affinity). <br /> <br /> ==Links==<br /> <br /> 1GPA is a [[Single protein]] structure of sequence from [http://en.wikipedia.org/wiki/Oryctolagus_cuniculus Oryctolagus cuniculus]. Additional information on 1GPA is available in a page on [http://pdb.rcsb.org/pdb/static.do?p=education_discussion/molecule_of_the_month/pdb24_1.html Glycogen Phosphorylase] at the RCSB PDB [http://pdb.rcsb.org/pdb/static.do?p=education_discussion/molecule_of_the_month/index.html Molecule of the Month]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1GPA OCA]. <br /> <br /> ==References==<br /> Structural mechanism for glycogen phosphorylase control by phosphorylation and AMP., Barford D, Hu SH, Johnson LN, J Mol Biol. 1991 Mar 5;218(1):233-60. PMID:[http://www.ncbi.nlm.nih.gov/pubmed/1900534 1900534]<br /> <br /> A New Allosteric site in Glycogen Phoshporylase b as a Target for Drug Interactions., Barford D, Hu SH, Johnson LN Structure. 2000. Vol. 8, No. 6, pp. 575-584.<br /> [[Category: Glycogen Phosphorylase]]<br /> [[Category: Oryctolagus cuniculus]]<br /> [[Category: Phosphorylase]]<br /> [[Category: Single protein]]<br /> [[Category: Barford, D.]]<br /> [[Category: Hu, S H.]]<br /> [[Category: Johnson, L N.]]<br /> [[Category: Glycogen phosphorylase]]<br /> <br /> ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Wed Jul 23 10:43:26 2008''</div>

Max Lein https://proteopedia.org/index.php?title=User:Max_Lein/Sandbox&diff=804581 User:Max Lein/Sandbox 2008-12-02T09:02:54Z

<p>Max Lein: </p> <hr /> <div>{{Seed}}<br /> [[Image:1gpa.png|left|200px]]<br /> <br /> <br /> {{STRUCTURE_1gpa| PDB=1gpa | SCENE= }} <br /> <br /> ==About this Structure==<br /> The PDB 1gpa contains 4 chains of the 'A' form of glycogen phosphorylase. Each subunit contains a phosphate group bound to Ser14, sulfate groups bound to two effector sites (sulfate acts as a mimic of phosphate groups), and the cofactor pyridoxal-5'-phosphate bound to K681. See the links section at the end of this page for links to more structural information on glycogen phosphorylase.<br /> <br /> ==Reaction==<br /> Glycogen phosphorylase (GP) catalyzes the degradation of the reducing end of glycogen into glucose-1-phosphate. It employs a cofactor called pyridoxal-5’ –phosphate, that is located in the active site and bound to a K681 residue with a Schiff base linkage. PLP shuttles the phosphate group onto the substrate.<br /> <br /> ==History==<br /> This protein comes from the muscle tissue of [http://en.wikipedia.org/wiki/Oryctolagus_cuniculus Oryctolagus cuniculus]. There is an isozyme from liver tissue that is regulated by glucagon instead of epinephrine, with a different gene that encodes it and different regulation properties.<br /> <br /> Glycogen phosphorylase was the first phosphorylase enzyme to be discovered, and the first example of regulation via covalent modification. <br /> <br /> In the 1930s, the first work done by Carl and Gerty Cori. They proved that the enzyme exists in 'A' and 'B' forms, and they showed that the reverse reaction produced glycogen. They won the Nobel Prize in 1947 along with Bernardo Housay of Argentina for their work on carbohydrate metabolism. This was also the first example of a polymerizing enzyme, inspiring others to look for other polymerizing enzymes.<br /> <br /> Subsequently, Earl Sutherland found that the 'B' form predominates in resting muscle and epinephrine triggers activation to form 'A'. Since then, many groups have worked on this enzyme, both to understand its mechanism and to discover drug targets. Crystal structures have been obtained for the protein in the 'A' and 'B' form, in the presence of natural substrates, inhibitors, and transition state analogs. Please see the end of this article for links to crystallographic information.<br /> <br /> ==Activity and Regulation of GP==<br /> In its active form, GP is a dimer of two identical subunits. The subunits make interactions that stabilize the final structure.<br /> <br /> Each Sub-unit contains 5 potential effector sites:<br /> 1. Ser14 phosphate-recognition site.<br /> 2. AMP activation / Glc-6-P inhibition site.<br /> 3. Catalytic site that binds glycogen, Glc-1-P<br /> 4. Inhibitor site, 12Å from catalytic site, binds caffeine and related compounds.<br /> 5. Glycogen storage site.<br /> <br /> There are two forms of the enzyme, designated as 'A' and 'B', that are controlled hormonally. The 'B' form is converted into the 'A' form by phosphorylase kinase, which catalyzes the addition of phosphate from ATP to Ser14 near the N-terminus. This represents the final step in a signal transduction cascade in response to the hormone epinephrine, associated with the 'fight-or-flight' response and causing an increase in available energy to the organism as a whole. The N-terminus contains a high percentage of basic residues, which interact favorably with a pocket of acidic residues in the 'B' form. Once Ser14 is phosphorylated, the N-terminus is forced ~50Å away from the acidic residues, settling into a region with several arginine side chains. The enzyme phosphatase is able to remove the phosphate and return GP to form 'B'.<br /> <br /> In addition, the 'A' and 'B' forms can be regulated futher by small molecules in the cell. This allows individual cells to ignore the hormonal signal if they already have enough available energy (at high concentrations of glucose derivatives or ATP, designated as the 'R' state), or activate GP without a hormonal signal when energy for the individual cell is needed (high concentrations of AMP, designated as the 'T' state). <br /> <br /> ==Links==<br /> <br /> 1GPA is a [[Single protein]] structure of sequence from [http://en.wikipedia.org/wiki/Oryctolagus_cuniculus Oryctolagus cuniculus]. Additional information on 1GPA is available in a page on [http://pdb.rcsb.org/pdb/static.do?p=education_discussion/molecule_of_the_month/pdb24_1.html Glycogen Phosphorylase] at the RCSB PDB [http://pdb.rcsb.org/pdb/static.do?p=education_discussion/molecule_of_the_month/index.html Molecule of the Month]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1GPA OCA]. <br /> <br /> ==References==<br /> Structural mechanism for glycogen phosphorylase control by phosphorylation and AMP., Barford D, Hu SH, Johnson LN, J Mol Biol. 1991 Mar 5;218(1):233-60. PMID:[http://www.ncbi.nlm.nih.gov/pubmed/1900534 1900534]<br /> <br /> A New Allosteric site in Glycogen Phoshporylase b as a Target for Drug Interactions., Barford D, Hu SH, Johnson LN Structure. 2000. Vol. 8, No. 6, pp. 575-584.<br /> [[Category: Glycogen Phosphorylase]]<br /> [[Category: Oryctolagus cuniculus]]<br /> [[Category: Phosphorylase]]<br /> [[Category: Single protein]]<br /> [[Category: Barford, D.]]<br /> [[Category: Hu, S H.]]<br /> [[Category: Johnson, L N.]]<br /> [[Category: Glycogen phosphorylase]]<br /> <br /> ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Wed Jul 23 10:43:26 2008''</div>

Max Lein https://proteopedia.org/index.php?title=User:Max_Lein/Sandbox&diff=804580 User:Max Lein/Sandbox 2008-12-02T09:00:26Z

<p>Max Lein: </p> <hr /> <div>{{Seed}}<br /> [[Image:1gpa.png|left|200px]]<br /> <br /> <br /> {{STRUCTURE_1gpa| PDB=1gpa | SCENE= }} <br /> <br /> ==About this Structure==<br /> The PDB 1gpa contains 4 chains of the 'A' form of glycogen phosphorylase. Each subunit contains a phosphate group bound to Ser14, sulfate groups bound to two effector sites (sulfate acts as a mimic of phosphate groups), and the cofactor pyridoxal-5'-phosphate bound to K681.<br /> <br /> ==Reaction==<br /> Glycogen phosphorylase (GP) catalyzes the degradation of the reducing end of glycogen into glucose-1-phosphate. It employs a cofactor called pyridoxal-5’ –phosphate, that is located in the active site and bound to a K681 residue with a Schiff base linkage. PLP shuttles the phosphate group onto the substrate.<br /> <br /> ==History==<br /> This protein comes from the muscle tissue of [http://en.wikipedia.org/wiki/Oryctolagus_cuniculus Oryctolagus cuniculus]. There is an isozyme from liver tissue that is regulated by glucagon instead of epinephrine, with a different gene that encodes it and different regulation properties.<br /> <br /> Glycogen phosphorylase was the first phosphorylase enzyme to be discovered, and the first example of regulation via covalent modification. <br /> <br /> In the 1930s, the first work done by Carl and Gerty Cori. They proved that the enzyme exists in 'A' and 'B' forms, and they showed that the reverse reaction produced glycogen. They won the Nobel Prize in 1947 along with Bernardo Housay of Argentina for their work on carbohydrate metabolism. This was also the first example of a polymerizing enzyme, inspiring others to look for other polymerizing enzymes.<br /> <br /> Subsequently, Earl Sutherland found that the 'B' form predominates in resting muscle and epinephrine triggers activation to form 'A'. Since then, many groups have worked on this enzyme, both to understand its mechanism and to discover drug targets. Crystal structures have been obtained for the protein in the 'A' and 'B' form, in the presence of natural substrates, inhibitors, and transition state analogs. Please see the end of this article for links to crystallographic information.<br /> <br /> ==Activity and Regulation of GP==<br /> In its active form, GP is a dimer of two identical subunits. The subunits make interactions that stabilize the final structure.<br /> <br /> Each Sub-unit contains 5 potential effector sites:<br /> 1. Ser14 phosphate-recognition site.<br /> 2. AMP activation / Glc-6-P inhibition site.<br /> 3. Catalytic site that binds glycogen, Glc-1-P<br /> 4. Inhibitor site, 12Å from catalytic site, binds caffeine and related compounds.<br /> 5. Glycogen storage site.<br /> <br /> There are two forms of the enzyme, designated as 'A' and 'B', that are controlled hormonally. The 'B' form is converted into the 'A' form by phosphorylase kinase, which catalyzes the addition of phosphate from ATP to Ser14 near the N-terminus. This represents the final step in a signal transduction cascade in response to the hormone epinephrine, associated with the 'fight-or-flight' response and causing an increase in available energy to the organism as a whole. The N-terminus contains a high percentage of basic residues, which interact favorably with a pocket of acidic residues in the 'B' form. Once Ser14 is phosphorylated, the N-terminus is forced ~50Å away from the acidic residues, settling into a region with several arginine side chains. The enzyme phosphatase is able to remove the phosphate and return GP to form 'B'.<br /> <br /> In addition, the 'A' and 'B' forms can be regulated futher by small molecules in the cell. This allows individual cells to ignore the hormonal signal if they already have enough available energy (at high concentrations of glucose derivatives or ATP, designated as the 'R' state), or activate GP without a hormonal signal when energy for the individual cell is needed (high concentrations of AMP, designated as the 'T' state). <br /> <br /> <br /> 1GPA is a [[Single protein]] structure of sequence from [http://en.wikipedia.org/wiki/Oryctolagus_cuniculus Oryctolagus cuniculus]. Additional information on 1GPA is available in a page on [http://pdb.rcsb.org/pdb/static.do?p=education_discussion/molecule_of_the_month/pdb24_1.html Glycogen Phosphorylase] at the RCSB PDB [http://pdb.rcsb.org/pdb/static.do?p=education_discussion/molecule_of_the_month/index.html Molecule of the Month]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1GPA OCA]. <br /> <br /> ==References==<br /> Structural mechanism for glycogen phosphorylase control by phosphorylation and AMP., Barford D, Hu SH, Johnson LN, J Mol Biol. 1991 Mar 5;218(1):233-60. PMID:[http://www.ncbi.nlm.nih.gov/pubmed/1900534 1900534]<br /> <br /> A New Allosteric site in Glycogen Phoshporylase b as a Target for Drug Interactions., Barford D, Hu SH, Johnson LN Structure. 2000. Vol. 8, No. 6, pp. 575-584.<br /> [[Category: Glycogen Phosphorylase]]<br /> [[Category: Oryctolagus cuniculus]]<br /> [[Category: Phosphorylase]]<br /> [[Category: Single protein]]<br /> [[Category: Barford, D.]]<br /> [[Category: Hu, S H.]]<br /> [[Category: Johnson, L N.]]<br /> [[Category: Glycogen phosphorylase]]<br /> <br /> ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Wed Jul 23 10:43:26 2008''</div>

Max Lein https://proteopedia.org/index.php?title=User:Max_Lein/Sandbox&diff=804579 User:Max Lein/Sandbox 2008-12-02T08:56:43Z

<p>Max Lein: </p> <hr /> <div>{{Seed}}<br /> [[Image:1gpa.png|left|200px]]<br /> <br /> <br /> {{STRUCTURE_1gpa| PDB=1gpa | SCENE= }} <br /> <br /> ==About this Structure==<br /> <br /> ==Reaction==<br /> Glycogen phosphorylase (GP) catalyzes the degradation of the reducing end of glycogen into glucose-1-phosphate. It employs a cofactor called pyridoxal-5’ –phosphate, that is located in the active site and bound to a K681 residue with a Schiff base linkage. PLP shuttles the phosphate group onto the substrate.<br /> <br /> ==History==<br /> This protein comes from the muscle tissue of [http://en.wikipedia.org/wiki/Oryctolagus_cuniculus Oryctolagus cuniculus]. There is an isozyme from liver tissue that is regulated by glucagon instead of epinephrine, with a different gene that encodes it and different regulation properties.<br /> <br /> Glycogen phosphorylase was the first phosphorylase enzyme to be discovered, and the first example of regulation via covalent modification. <br /> <br /> In the 1930s, the first work done by Carl and Gerty Cori. They proved that the enzyme exists in 'A' and 'B' forms, and they showed that the reverse reaction produced glycogen. They won the Nobel Prize in 1947 along with Bernardo Housay of Argentina for their work on carbohydrate metabolism. This was also the first example of a polymerizing enzyme, inspiring others to look for other polymerizing enzymes.<br /> <br /> Subsequently, Earl Sutherland found that the 'B' form predominates in resting muscle and epinephrine triggers activation to form 'A'. Since then, many groups have worked on this enzyme, both to understand its mechanism and to discover drug targets. Crystal structures have been obtained for the protein in the 'A' and 'B' form, in the presence of natural substrates, inhibitors, and transition state analogs. Please see the end of this article for links to crystallographic information.<br /> <br /> ==Activity and Regulation of GP==<br /> In its active form, GP is a dimer of two identical subunits. The subunits make interactions that stabilize the final structure.<br /> <br /> Each Sub-unit contains 5 potential effector sites:<br /> 1. Ser14 phosphate-recognition site.<br /> 2. AMP activation / Glc-6-P inhibition site.<br /> 3. Catalytic site that binds glycogen, Glc-1-P<br /> 4. Inhibitor site, 12Å from catalytic site, binds caffeine and related compounds.<br /> 5. Glycogen storage site.<br /> <br /> There are two forms of the enzyme, designated as 'A' and 'B', that are controlled hormonally. The 'B' form is converted into the 'A' form by phosphorylase kinase, which catalyzes the addition of phosphate from ATP to Ser14 near the N-terminus. This represents the final step in a signal transduction cascade in response to the hormone epinephrine, associated with the 'fight-or-flight' response and causing an increase in available energy to the organism as a whole. The N-terminus contains a high percentage of basic residues, which interact favorably with a pocket of acidic residues in the 'B' form. Once Ser14 is phosphorylated, the N-terminus is forced ~50Å away from the acidic residues, settling into a region with several arginine side chains. The enzyme phosphatase is able to remove the phosphate and return GP to form 'B'.<br /> <br /> In addition, the 'A' and 'B' forms can be regulated futher by small molecules in the cell. This allows individual cells to ignore the hormonal signal if they already have enough available energy (at high concentrations of glucose derivatives or ATP, designated as the 'R' state), or activate GP without a hormonal signal when energy for the individual cell is needed (high concentrations of AMP, designated as the 'T' state). <br /> <br /> <br /> 1GPA is a [[Single protein]] structure of sequence from [http://en.wikipedia.org/wiki/Oryctolagus_cuniculus Oryctolagus cuniculus]. Additional information on 1GPA is available in a page on [http://pdb.rcsb.org/pdb/static.do?p=education_discussion/molecule_of_the_month/pdb24_1.html Glycogen Phosphorylase] at the RCSB PDB [http://pdb.rcsb.org/pdb/static.do?p=education_discussion/molecule_of_the_month/index.html Molecule of the Month]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1GPA OCA]. <br /> <br /> ==References==<br /> Structural mechanism for glycogen phosphorylase control by phosphorylation and AMP., Barford D, Hu SH, Johnson LN, J Mol Biol. 1991 Mar 5;218(1):233-60. PMID:[http://www.ncbi.nlm.nih.gov/pubmed/1900534 1900534]<br /> <br /> A New Allosteric site in Glycogen Phoshporylase b as a Target for Drug Interactions., Barford D, Hu SH, Johnson LN Structure. 2000. Vol. 8, No. 6, pp. 575-584.<br /> [[Category: Glycogen Phosphorylase]]<br /> [[Category: Oryctolagus cuniculus]]<br /> [[Category: Phosphorylase]]<br /> [[Category: Single protein]]<br /> [[Category: Barford, D.]]<br /> [[Category: Hu, S H.]]<br /> [[Category: Johnson, L N.]]<br /> [[Category: Glycogen phosphorylase]]<br /> <br /> ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Wed Jul 23 10:43:26 2008''</div>

Max Lein https://proteopedia.org/index.php?title=User:Max_Lein/Sandbox&diff=804578 User:Max Lein/Sandbox 2008-12-02T08:33:16Z

<p>Max Lein: </p> <hr /> <div>{{Seed}}<br /> [[Image:1gpa.png|left|200px]]<br /> <br /> <br /> {{STRUCTURE_1gpa| PDB=1gpa | SCENE= }} <br /> <br /> ===STRUCTURAL MECHANISM FOR GLYCOGEN PHOSPHORYLASE CONTROL BY PHOSPHORYLATION AND AMP===<br /> <br /> <br /> <br /> ==About this Structure==<br /> <br /> ==Reaction==<br /> Glycogen phosphorylase (GP) catalyzes the degradation of the reducing end of glycogen into glucose-1-phosphate. It employs a cofactor called pyridoxal-5’ –phosphate, that is located in the active site and bound to a K681 residue with a Schiff base linkage. PLP shuttles the phosphate group onto the substrate.<br /> <br /> ==History==<br /> This protein comes from the muscle tissue of [http://en.wikipedia.org/wiki/Oryctolagus_cuniculus Oryctolagus cuniculus]. There is an isozyme from liver tissue that is regulated by glucagon instead of epinephrine, with a different gene that encodes it and different regulation properties.<br /> <br /> Glycogen phosphorylase was the first phosphorylase enzyme to be discovered, and the first example of regulation via covalent modification. <br /> <br /> In the 1930s, the first work done by Carl and Gerty Cori. They proved that the enzyme exists in 'A' and 'B' forms, and they showed that the reverse reaction produced glycogen. They won the Nobel Prize in 1947 along with Bernardo Housay of Argentina for their work on carbohydrate metabolism. This was also the first example of a polymerizing enzyme, inspiring others to look for other polymerizing enzymes.<br /> <br /> Subsequently, Earl Sutherland found that the 'B' form predominates in resting muscle and epinephrine triggers activation to form 'A'. Since then, many groups have worked on this enzyme, both to understand its mechanism and to discover drug targets. Crystal structures have been obtained for the protein in the 'A' and 'B' form, in the presence of natural substrates, inhibitors, and transition state analogs. Please see the end of this article for links to crystallographic information.<br /> <br /> ==Activity and Regulation of GP==<br /> In its active form, GP is a dimer of two identical subunits. The subunits make interactions that stabilize the final structure.<br /> <br /> Each Sub-unit contains 5 potential effector sites:<br /> 1. Ser14 phosphate-recognition site.<br /> 2. AMP activation / Glc-6-P inhibition site.<br /> 3. Catalytic site that binds glycogen, Glc-1-P<br /> 4. Inhibitor site, 12Å from catalytic site, binds caffeine and related compounds.<br /> 5. Glycogen storage site.<br /> <br /> There are two forms of the enzyme, designated as 'A' and 'B', that are controlled hormonally. The 'B' form is converted into the 'A' form by phosphorylase kinase, which catalyzes the addition of phosphate from ATP to Ser14 near the N-terminus. This represents the final step in a signal transduction cascade in response to the hormone epinephrine, associated with the 'fight-or-flight' response and causing an increase in available energy to the organism as a whole. The N-terminus contains a high percentage of basic residues, which interact favorably with a pocket of acidic residues in the 'B' form. Once Ser14 is phosphorylated, the N-terminus is forced ~50Å away from the acidic residues, settling into a region with several arginine side chains. The enzyme phosphatase is able to remove the phosphate and return GP to form 'B'.<br /> <br /> In addition, the 'A' and 'B' forms can be regulated futher by small molecules in the cell. This allows individual cells to ignore the hormonal signal if they already have enough available energy (at high concentrations of glucose derivatives or ATP, designated as the 'R' state), or activate GP without a hormonal signal when energy for the individual cell is needed (high concentrations of AMP, designated as the 'T' state). <br /> <br /> <br /> 1GPA is a [[Single protein]] structure of sequence from [http://en.wikipedia.org/wiki/Oryctolagus_cuniculus Oryctolagus cuniculus]. Additional information on 1GPA is available in a page on [http://pdb.rcsb.org/pdb/static.do?p=education_discussion/molecule_of_the_month/pdb24_1.html Glycogen Phosphorylase] at the RCSB PDB [http://pdb.rcsb.org/pdb/static.do?p=education_discussion/molecule_of_the_month/index.html Molecule of the Month]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1GPA OCA]. <br /> <br /> ==References==<br /> Structural mechanism for glycogen phosphorylase control by phosphorylation and AMP., Barford D, Hu SH, Johnson LN, J Mol Biol. 1991 Mar 5;218(1):233-60. PMID:[http://www.ncbi.nlm.nih.gov/pubmed/1900534 1900534]<br /> <br /> A New Allosteric site in Glycogen Phoshporylase b as a Target for Drug Interactions., Barford D, Hu SH, Johnson LN Structure. 2000. Vol. 8, No. 6, pp. 575-584.<br /> [[Category: Glycogen Phosphorylase]]<br /> [[Category: Oryctolagus cuniculus]]<br /> [[Category: Phosphorylase]]<br /> [[Category: Single protein]]<br /> [[Category: Barford, D.]]<br /> [[Category: Hu, S H.]]<br /> [[Category: Johnson, L N.]]<br /> [[Category: Glycogen phosphorylase]]<br /> <br /> ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Wed Jul 23 10:43:26 2008''</div>

Max Lein https://proteopedia.org/index.php?title=User:Max_Lein/Sandbox&diff=804576 User:Max Lein/Sandbox 2008-12-02T08:27:11Z

<p>Max Lein: </p> <hr /> <div>{{Seed}}<br /> [[Image:1gpa.png|left|200px]]<br /> <br /> <br /> {{STRUCTURE_1gpa| PDB=1gpa | SCENE= }} <br /> <br /> ===STRUCTURAL MECHANISM FOR GLYCOGEN PHOSPHORYLASE CONTROL BY PHOSPHORYLATION AND AMP===<br /> <br /> <br /> <br /> ==About this Structure==<br /> <br /> ==Reaction==<br /> Glycogen phosphorylase (GP) catalyzes the degradation of the reducing end of glycogen into glucose-1-phosphate. It employs a cofactor called pyridoxal-5’ –phosphate, that is located in the active site and bound to a K681 residue with a Schiff base linkage. PLP shuttles the phosphate group onto the substrate.<br /> <br /> ==History==<br /> This protein comes from the muscle tissue of [http://en.wikipedia.org/wiki/Oryctolagus_cuniculus Oryctolagus cuniculus]. There is an isozyme from liver tissue that is regulated by glucagon instead of epinephrine, with a different gene that encodes it and different regulation properties.<br /> <br /> Glycogen phosphorylase was the first phosphorylase enzyme to be discovered, and the first example of regulation via covalent modification. <br /> <br /> In the 1930s, the first work done by Carl and Gerty Cori. They proved that the enzyme exists in 'A' and 'B' forms, and they showed that the reverse reaction produced glycogen. They won the Nobel Prize in 1947 along with Bernardo Housay of Argentina for their work on carbohydrate metabolism. This was also the first example of a polymerizing enzyme, inspiring others to look for other polymerizing enzymes.<br /> <br /> Subsequently, Earl Sutherland found that the 'B' form predominates in resting muscle and epinephrine triggers activation to form 'A'. Since then, many groups have worked on this enzyme, both to understand its mechanism and to discover drug targets. Crystal structures have been obtained for the protein in the 'A' and 'B' form, in the presence of natural substrates, inhibitors, and transition state analogs. Please see the end of this article for links to crystallographic information.<br /> <br /> ==Activity and Regulation of GP==<br /> In its active form, GP is a dimer of two identical subunits. The subunits make interactions that stabilize the final structure.<br /> <br /> Each Sub-unit contains 5 potential effector sites:<br /> 1. Ser14 phosphate-recognition site.<br /> 2. AMP activation / Glc-6-P inhibition site.<br /> 3. Catalytic site that binds glycogen, Glc-1-P<br /> 4. Inhibitor site, 12Å from catalytic site, binds caffeine and related compounds.<br /> 5. Glycogen storage site.<br /> <br /> There are two forms of the enzyme, designated as 'A' and 'B', that are controlled hormonally. The 'B' form is converted into the 'A' form by phosphorylase kinase, which catalyzes the addition of phosphate from ATP to Ser14 near the N-terminus. This represents the final step in a signal transduction cascade in response to the hormone epinephrine, associated with the 'fight-or-flight' response and causing an increase in available energy to the organism as a whole. The N-terminus contains a high percentage of basic residues, which interact favorably with a pocket of acidic residues in the 'B' form. Once Ser14 is phosphorylated, the N-terminus is forced ~50Å away from the acidic residues, settling into a region with several arginine side chains. The enzyme phosphatase is able to remove the phosphate and return GP to form 'B'.<br /> <br /> In addition, the 'A' and 'B' forms can be regulated futher by small molecules in the cell. This allows individual cells to ignore the hormonal signal if they already have enough available energy (at high concentrations of glucose derivatives or ATP, designated as the 'R' state), or activate GP without a hormonal signal when energy for the individual cell is needed (high concentrations of AMP, designated as the 'T' state). <br /> <br /> <br /> 1GPA is a [[Single protein]] structure of sequence from [http://en.wikipedia.org/wiki/Oryctolagus_cuniculus Oryctolagus cuniculus]. Additional information on 1GPA is available in a page on [http://pdb.rcsb.org/pdb/static.do?p=education_discussion/molecule_of_the_month/pdb24_1.html Glycogen Phosphorylase] at the RCSB PDB [http://pdb.rcsb.org/pdb/static.do?p=education_discussion/molecule_of_the_month/index.html Molecule of the Month]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1GPA OCA]. <br /> <br /> ==Reference==<br /> Structural mechanism for glycogen phosphorylase control by phosphorylation and AMP., Barford D, Hu SH, Johnson LN, J Mol Biol. 1991 Mar 5;218(1):233-60. PMID:[http://www.ncbi.nlm.nih.gov/pubmed/1900534 1900534]<br /> [[Category: Glycogen Phosphorylase]]<br /> [[Category: Oryctolagus cuniculus]]<br /> [[Category: Phosphorylase]]<br /> [[Category: Single protein]]<br /> [[Category: Barford, D.]]<br /> [[Category: Hu, S H.]]<br /> [[Category: Johnson, L N.]]<br /> [[Category: Glycogen phosphorylase]]<br /> <br /> ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Wed Jul 23 10:43:26 2008''</div>

Max Lein https://proteopedia.org/index.php?title=User:Max_Lein/Sandbox&diff=804570 User:Max Lein/Sandbox 2008-12-02T07:36:35Z

<p>Max Lein: </p> <hr /> <div>{{Seed}}<br /> [[Image:1gpa.png|left|200px]]<br /> <br /> <br /> {{STRUCTURE_1gpa| PDB=1gpa | SCENE= }} <br /> <br /> ===STRUCTURAL MECHANISM FOR GLYCOGEN PHOSPHORYLASE CONTROL BY PHOSPHORYLATION AND AMP===<br /> <br /> <br /> <br /> ==About this Structure==<br /> <br /> ==Reaction==<br /> Glycogen phosphorylase catalyzes the degradation of glycogen into glucose-1'-phosphate.<br /> <br /> ==History==<br /> Glycogen phosphorylase was the first phosphorylase enzyme to be discovered, and the first example of regulation via covalent modification. <br /> <br /> In the 1930s, the first work done by Carl and Gerty Cori. They proved that the enzyme exists in 'A' and 'B' forms, and they showed that the reverse reaction produced glycogen. They won the Nobel Prize in 1947 along with Bernardo Housay of Argentina for their work on carbohydrate metabolism. This was also the first example of a polymerizing enzyme, inspiring others to look for other polymerizing enzymes.<br /> <br /> Subsequently, Earl Sutherland found that the 'B' form predominates in resting muscle and epinephrine triggers activation to form 'A'. Since then, many groups have worked on this enzyme, both to understand its mechanism and to discover drug targets. Crystal structures have been obtained for the protein in the 'A' and 'B' form, in the presence of natural substrates, inhibitors, and transition state analogs. Please see the end of this article for links to crystallographic information.<br /> <br /> ==Facts about GP==<br /> Protein comes from rabbit muscle tissue, where energy from glucose is needed. There is an isozyme from liver tissue that is regulated by glucagon instead of epinephrine, with a different gene that encodes it and different regulation properties.<br /> Activity and Regulation of GP<br /> 1. GP catalyzes the clipping of a glucose molecule off of the reducing end of glycogen. It employs a cofactor called pyridoxal-5’ –phosphate, that is located in the active site and bound to a lysine residue with a Schiff base linkage. PLP shuttles the phosphate group onto the substrate.<br /> 2. There are two forms, A and B, and two states, T and R, for the enzyme. <br /> B = nearly inactive dimer, stabilized by electrostatics at N-terminus (w/basic residues) interacting with pocket of acidic residues.<br /> Phosphorylase kinase catalyzes addition of phosphate to Ser14, tightens structure of N-terminal portion of each chain, resulting in conformation change to form A.<br /> Phosphorylation causes electrostatic interference between phosphate group and acidic residues, forcing the N-terminal domain out of the acidic environment and into a region with several arginine side chains.<br /> Phosphatase removes phosphate, returns GP to form B.<br /> Response to hormone epinephrine (in muscle), (fight-or-flight response) or glucagon (in liver), increases available energy to organism as a whole.<br /> - In b form, enzyme can be activated:<br /> Activated by AMP, (cell doesn’t get signal, but needs energy for itself).<br /> Inactivated by ATP, glucose (cell already has enough energy for itself, phosphorylation will not activate)<br /> - Having two overlaid levels of control allows the appropriate response in either situation.<br /> - Phosphoglucomutase shifts carbon chain over 1.<br /> <br /> <br /> 1GPA is a [[Single protein]] structure of sequence from [http://en.wikipedia.org/wiki/Oryctolagus_cuniculus Oryctolagus cuniculus]. Additional information on 1GPA is available in a page on [http://pdb.rcsb.org/pdb/static.do?p=education_discussion/molecule_of_the_month/pdb24_1.html Glycogen Phosphorylase] at the RCSB PDB [http://pdb.rcsb.org/pdb/static.do?p=education_discussion/molecule_of_the_month/index.html Molecule of the Month]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1GPA OCA]. <br /> <br /> ==Reference==<br /> Structural mechanism for glycogen phosphorylase control by phosphorylation and AMP., Barford D, Hu SH, Johnson LN, J Mol Biol. 1991 Mar 5;218(1):233-60. PMID:[http://www.ncbi.nlm.nih.gov/pubmed/1900534 1900534]<br /> [[Category: Glycogen Phosphorylase]]<br /> [[Category: Oryctolagus cuniculus]]<br /> [[Category: Phosphorylase]]<br /> [[Category: Single protein]]<br /> [[Category: Barford, D.]]<br /> [[Category: Hu, S H.]]<br /> [[Category: Johnson, L N.]]<br /> [[Category: Glycogen phosphorylase]]<br /> <br /> ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Wed Jul 23 10:43:26 2008''</div>

Max Lein https://proteopedia.org/index.php?title=User:Max_Lein/Sandbox&diff=804569 User:Max Lein/Sandbox 2008-12-02T07:35:01Z

<p>Max Lein: </p> <hr /> <div>{{Seed}}<br /> [[Image:1gpa.png|left|200px]]<br /> <br /> <br /> {{STRUCTURE_1gpa| PDB=1gpa | SCENE= }} <br /> <br /> ===STRUCTURAL MECHANISM FOR GLYCOGEN PHOSPHORYLASE CONTROL BY PHOSPHORYLATION AND AMP===<br /> <br /> <br /> <br /> ==About this Structure==<br /> <br /> ==Reaction==<br /> Glycogen phosphorylase catalyzes the degradation of glycogen into glucose-1'-phosphate.<br /> <br /> ==History==<br /> Glycogen phosphorylase was the first phosphorylase enzyme to be discovered, and the first example of regulation via covalent modification. <br /> <br /> In the 1930s, the first work done by Carl and Gerty Cori. They proved that the enzyme exists in 'A' and 'B' forms, and they showed that the reverse reaction produced glycogen. They won the Nobel Prize in 1947 along with Bernardo Housay of Argentina for their work on carbohydrate metabolism. This was also the first example of a polymerizing enzyme, inspiring others to look for other polymerizing enzymes.<br /> <br /> Subsequently, Earl Sutherland found that the 'B' form predominates in resting muscle and epinephrine triggers activation to form 'A'. Since then, many groups have worked on this enzyme, both to understand its mechanism and to discover drug targets. Crystal structures have been obtained for the protein in the 'A' and 'B' form, in the presence of natural substrates, inhibitors, and transition state analogs. Please see the end of this article for a list of relevant PDB files, along with a brief description. <br /> <br /> ==Facts about GP==<br /> Protein comes from rabbit muscle tissue, where energy from glucose is needed. There is an isozyme from liver tissue that is regulated by glucagon instead of epinephrine, with a different gene that encodes it and different regulation properties.<br /> Activity and Regulation of GP<br /> 1. GP catalyzes the clipping of a glucose molecule off of the reducing end of glycogen. It employs a cofactor called pyridoxal-5’ –phosphate, that is located in the active site and bound to a lysine residue with a Schiff base linkage. PLP shuttles the phosphate group onto the substrate.<br /> 2. There are two forms, A and B, and two states, T and R, for the enzyme. <br /> B = nearly inactive dimer, stabilized by electrostatics at N-terminus (w/basic residues) interacting with pocket of acidic residues.<br /> Phosphorylase kinase catalyzes addition of phosphate to Ser14, tightens structure of N-terminal portion of each chain, resulting in conformation change to form A.<br /> Phosphorylation causes electrostatic interference between phosphate group and acidic residues, forcing the N-terminal domain out of the acidic environment and into a region with several arginine side chains.<br /> Phosphatase removes phosphate, returns GP to form B.<br /> Response to hormone epinephrine (in muscle), (fight-or-flight response) or glucagon (in liver), increases available energy to organism as a whole.<br /> - In b form, enzyme can be activated:<br /> Activated by AMP, (cell doesn’t get signal, but needs energy for itself).<br /> Inactivated by ATP, glucose (cell already has enough energy for itself, phosphorylation will not activate)<br /> - Having two overlaid levels of control allows the appropriate response in either situation.<br /> - Phosphoglucomutase shifts carbon chain over 1.<br /> <br /> <br /> 1GPA is a [[Single protein]] structure of sequence from [http://en.wikipedia.org/wiki/Oryctolagus_cuniculus Oryctolagus cuniculus]. Additional information on 1GPA is available in a page on [http://pdb.rcsb.org/pdb/static.do?p=education_discussion/molecule_of_the_month/pdb24_1.html Glycogen Phosphorylase] at the RCSB PDB [http://pdb.rcsb.org/pdb/static.do?p=education_discussion/molecule_of_the_month/index.html Molecule of the Month]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1GPA OCA]. <br /> <br /> ==Reference==<br /> Structural mechanism for glycogen phosphorylase control by phosphorylation and AMP., Barford D, Hu SH, Johnson LN, J Mol Biol. 1991 Mar 5;218(1):233-60. PMID:[http://www.ncbi.nlm.nih.gov/pubmed/1900534 1900534]<br /> [[Category: Glycogen Phosphorylase]]<br /> [[Category: Oryctolagus cuniculus]]<br /> [[Category: Phosphorylase]]<br /> [[Category: Single protein]]<br /> [[Category: Barford, D.]]<br /> [[Category: Hu, S H.]]<br /> [[Category: Johnson, L N.]]<br /> [[Category: Glycogen phosphorylase]]<br /> <br /> ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Wed Jul 23 10:43:26 2008''</div>

Max Lein https://proteopedia.org/index.php?title=User:Max_Lein/Sandbox&diff=804568 User:Max Lein/Sandbox 2008-12-02T07:18:06Z

<p>Max Lein: </p> <hr /> <div>{{Seed}}<br /> [[Image:1gpa.png|left|200px]]<br /> <br /> <br /> {{STRUCTURE_1gpa| PDB=1gpa | SCENE= }} <br /> <br /> ===STRUCTURAL MECHANISM FOR GLYCOGEN PHOSPHORYLASE CONTROL BY PHOSPHORYLATION AND AMP===<br /> <br /> <br /> <br /> ==About this Structure==<br /> 1GPA is a [[Single protein]] structure of sequence from [http://en.wikipedia.org/wiki/Oryctolagus_cuniculus Oryctolagus cuniculus]. Additional information on 1GPA is available in a page on [http://pdb.rcsb.org/pdb/static.do?p=education_discussion/molecule_of_the_month/pdb24_1.html Glycogen Phosphorylase] at the RCSB PDB [http://pdb.rcsb.org/pdb/static.do?p=education_discussion/molecule_of_the_month/index.html Molecule of the Month]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1GPA OCA]. <br /> <br /> ==Reference==<br /> Structural mechanism for glycogen phosphorylase control by phosphorylation and AMP., Barford D, Hu SH, Johnson LN, J Mol Biol. 1991 Mar 5;218(1):233-60. PMID:[http://www.ncbi.nlm.nih.gov/pubmed/1900534 1900534]<br /> [[Category: Glycogen Phosphorylase]]<br /> [[Category: Oryctolagus cuniculus]]<br /> [[Category: Phosphorylase]]<br /> [[Category: Single protein]]<br /> [[Category: Barford, D.]]<br /> [[Category: Hu, S H.]]<br /> [[Category: Johnson, L N.]]<br /> [[Category: Glycogen phosphorylase]]<br /> <br /> ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Wed Jul 23 10:43:26 2008''</div>

Max Lein https://proteopedia.org/index.php?title=User:Max_Lein/Sandbox&diff=804567 User:Max Lein/Sandbox 2008-12-02T07:14:46Z

<p>Max Lein: </p> <hr /> <div>{{Seed}}<br /> [[Image:1gpa.png|left|200px]]<br /> <br /> <br /> {{STRUCTURE_1gpa| PDB=1gpa | SCENE= }} <br /> <br /> ===STRUCTURAL MECHANISM FOR GLYCOGEN PHOSPHORYLASE CONTROL BY PHOSPHORYLATION AND AMP===<br /> <br /> <br /> <br /> {{ABSTRACT_PUBMED_1900534}}<br /> <br /> ==About this Structure==<br /> 1GPA is a [[Single protein]] structure of sequence from [http://en.wikipedia.org/wiki/Oryctolagus_cuniculus Oryctolagus cuniculus]. Additional information on 1GPA is available in a page on [http://pdb.rcsb.org/pdb/static.do?p=education_discussion/molecule_of_the_month/pdb24_1.html Glycogen Phosphorylase] at the RCSB PDB [http://pdb.rcsb.org/pdb/static.do?p=education_discussion/molecule_of_the_month/index.html Molecule of the Month]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1GPA OCA]. <br /> <br /> ==Reference==<br /> Structural mechanism for glycogen phosphorylase control by phosphorylation and AMP., Barford D, Hu SH, Johnson LN, J Mol Biol. 1991 Mar 5;218(1):233-60. PMID:[http://www.ncbi.nlm.nih.gov/pubmed/1900534 1900534]<br /> [[Category: Glycogen Phosphorylase]]<br /> [[Category: Oryctolagus cuniculus]]<br /> [[Category: Phosphorylase]]<br /> [[Category: Single protein]]<br /> [[Category: Barford, D.]]<br /> [[Category: Hu, S H.]]<br /> [[Category: Johnson, L N.]]<br /> [[Category: Glycogen phosphorylase]]<br /> <br /> ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Wed Jul 23 10:43:26 2008''</div>

Max Lein https://proteopedia.org/index.php?title=User:Max_Lein/Sandbox&diff=804566 User:Max Lein/Sandbox 2008-12-02T07:10:39Z

<p>Max Lein: </p> <hr /> <div>==This is a placeholder==<br /> This is a placeholder text to help you get started in <br /> placing a Jmol applet on your page. At any time, click<br /> "Show Preview" at the bottom of this page to see how it goes.<br /> <br /> Replace the PDB id after the STRUCTURE_ and after PDB= to load <br /> and display another structure.<br /> <br /> {{STRUCTURE_1GPB | PDB=1GPB | SCENE= 1 }}<br /> <br /> {{STRUCTURE_1GPA | PDB=1GPA | SCENE= 2 }}<br /> <br /> Where is this text?</div>

Max Lein https://proteopedia.org/index.php?title=User:Max_Lein/Sandbox&diff=804565 User:Max Lein/Sandbox 2008-12-02T07:06:19Z

<p>Max Lein: Glycogen Phosphorylase from Oryctolagus Cuniculus</p> <hr /> <div>==This is a placeholder==<br /> This is a placeholder text to help you get started in <br /> placing a Jmol applet on your page. At any time, click<br /> "Show Preview" at the bottom of this page to see how it goes.<br /> <br /> Replace the PDB id after the STRUCTURE_ and after PDB= to load <br /> and display another structure.<br /> <br /> {{STRUCTURE_1GPB | PDB=1GPB | SCENE= }}<br /> <br /> Where is this text?</div>

Max Lein https://proteopedia.org/index.php?title=User:Max_Lein/Sandbox&diff=802411 User:Max Lein/Sandbox 2008-11-25T15:12:03Z

<p>Max Lein: 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...</p> <hr /> <div>==This is a placeholder==<br /> This is a placeholder text to help you get started in <br /> placing a Jmol applet on your page. At any time, click<br /> "Show Preview" at the bottom of this page to see how it goes.<br /> <br /> Replace the PDB id after the STRUCTURE_ and after PDB= to load <br /> and display another structure.<br /> <br /> {{STRUCTURE_1GPB | PDB=1GPB | SCENE= }}</div>

Max Lein https://proteopedia.org/index.php?title=User:Max_Lein&diff=802409 User:Max Lein 2008-11-25T15:10:29Z

<p>Max Lein: </p> <hr /> <div>Chem grad student @ UMass Amherst<br /> <br /> *[[User:Max Lein/Sandbox]]</div>

Max Lein