Globular Proteins - Revision history

Alexander Berchansky at 10:30, 16 May 2017

Alexander Berchansky — Tue, 16 May 2017 10:30:29 GMT

←Older revision		Revision as of 10:30, 16 May 2017
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-	<StructureSection load='1a7v' size='450' frame='true' ~~align~~='right' scene ='Globular_Proteins/Two_layers/3' caption='' >__NOTOC__	+	<StructureSection load='1a7v' size='450' frame='true' side='right' scene ='Globular_Proteins/Two_layers/3' caption='' >__NOTOC__
	Globular proteins have a 3D molecular structure that has a shape that is anywhere from a sphere to a cigar. Usually the structure of a globular protein is divided into three or four levels. The primary structure is simply the sequence of amino acids forming the peptide chain. The peptide chain can be folded in an ordered and repetitive fashion, and the structures with ordered and repetitive conformations are called [[Secondary_structure\|secondary structures]]. [[Helices_in_Proteins\|Helices]], [[Sheets in Proteins\|β-sheets]] and [[Turns in Proteins\|turns]] are three important types of secondary structures. Turns are classified as a secondary structure even though their structures are ordered but not repetitive. The tertiary structure is the overall 3D structure of a globular protein and is produced by folding the helices and sheets upon themselves with turns and [[Loops in Proteins\|loops]] forming the folds. Non-covalent molecular attractions are important forces in maintaining the folded conformation of a globular protein. For the most part, these attractions are between the atoms of the side chains but can be between the side chains and a bound ligand. Hydrogen bonds between back bone atoms are important in maintaining secondary structures, and those between side chains are involved in maintaining the tertiary structure. Examples of finding and visualizing both types in globular proteins are at [[Hydrogen bonds \|hydrogen bonds]]. The attractive forces of [[Salt_bridges \|salt bridges]] are important in maintaining some tertiary structures, but they also can be involved in the binding of ligands. The Disulfide bond is the one type of covalent bond that can play an important role in maintaining the tertiary structure as well as connecting two or more peptide chains together. Links to sites having structures that illustrate disulfide bonds are at [[Cystine]]. Some globular proteins have a quaternary structure, and it is formed when two or more globular protein molecules (monomer) join together and form a multimeric unit. [[Hemoglobin]] is a good example of a protein that has a quarternary structure.		Globular proteins have a 3D molecular structure that has a shape that is anywhere from a sphere to a cigar. Usually the structure of a globular protein is divided into three or four levels. The primary structure is simply the sequence of amino acids forming the peptide chain. The peptide chain can be folded in an ordered and repetitive fashion, and the structures with ordered and repetitive conformations are called [[Secondary_structure\|secondary structures]]. [[Helices_in_Proteins\|Helices]], [[Sheets in Proteins\|β-sheets]] and [[Turns in Proteins\|turns]] are three important types of secondary structures. Turns are classified as a secondary structure even though their structures are ordered but not repetitive. The tertiary structure is the overall 3D structure of a globular protein and is produced by folding the helices and sheets upon themselves with turns and [[Loops in Proteins\|loops]] forming the folds. Non-covalent molecular attractions are important forces in maintaining the folded conformation of a globular protein. For the most part, these attractions are between the atoms of the side chains but can be between the side chains and a bound ligand. Hydrogen bonds between back bone atoms are important in maintaining secondary structures, and those between side chains are involved in maintaining the tertiary structure. Examples of finding and visualizing both types in globular proteins are at [[Hydrogen bonds \|hydrogen bonds]]. The attractive forces of [[Salt_bridges \|salt bridges]] are important in maintaining some tertiary structures, but they also can be involved in the binding of ligands. The Disulfide bond is the one type of covalent bond that can play an important role in maintaining the tertiary structure as well as connecting two or more peptide chains together. Links to sites having structures that illustrate disulfide bonds are at [[Cystine]]. Some globular proteins have a quaternary structure, and it is formed when two or more globular protein molecules (monomer) join together and form a multimeric unit. [[Hemoglobin]] is a good example of a protein that has a quarternary structure.

Alexander Berchansky at 10:00, 21 August 2013

Alexander Berchansky — Wed, 21 Aug 2013 10:00:36 GMT

←Older revision		Revision as of 10:00, 21 August 2013
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-	<StructureSection load='1a7v' size='~~500~~' frame='true' align='right' scene ='Globular_Proteins/Two_layers/3' caption='' >__NOTOC__	+	<StructureSection load='1a7v' size='450' frame='true' align='right' scene ='Globular_Proteins/Two_layers/3' caption='' >__NOTOC__
	Globular proteins have a 3D molecular structure that has a shape that is anywhere from a sphere to a cigar. Usually the structure of a globular protein is divided into three or four levels. The primary structure is simply the sequence of amino acids forming the peptide chain. The peptide chain can be folded in an ordered and repetitive fashion, and the structures with ordered and repetitive conformations are called [[Secondary_structure\|secondary structures]]. [[Helices_in_Proteins\|Helices]], [[Sheets in Proteins\|β-sheets]] and [[Turns in Proteins\|turns]] are three important types of secondary structures. Turns are classified as a secondary structure even though their structures are ordered but not repetitive. The tertiary structure is the overall 3D structure of a globular protein and is produced by folding the helices and sheets upon themselves with turns and [[Loops in Proteins\|loops]] forming the folds. Non-covalent molecular attractions are important forces in maintaining the folded conformation of a globular protein. For the most part, these attractions are between the atoms of the side chains but can be between the side chains and a bound ligand. Hydrogen bonds between back bone atoms are important in maintaining secondary structures, and those between side chains are involved in maintaining the tertiary structure. Examples of finding and visualizing both types in globular proteins are at [[Hydrogen bonds \|hydrogen bonds]]. The attractive forces of [[Salt_bridges \|salt bridges]] are important in maintaining some tertiary structures, but they also can be involved in the binding of ligands. The Disulfide bond is the one type of covalent bond that can play an important role in maintaining the tertiary structure as well as connecting two or more peptide chains together. Links to sites having structures that illustrate disulfide bonds are at [[Cystine]]. Some globular proteins have a quaternary structure, and it is formed when two or more globular protein molecules (monomer) join together and form a multimeric unit. [[Hemoglobin]] is a good example of a protein that has a quarternary structure.		Globular proteins have a 3D molecular structure that has a shape that is anywhere from a sphere to a cigar. Usually the structure of a globular protein is divided into three or four levels. The primary structure is simply the sequence of amino acids forming the peptide chain. The peptide chain can be folded in an ordered and repetitive fashion, and the structures with ordered and repetitive conformations are called [[Secondary_structure\|secondary structures]]. [[Helices_in_Proteins\|Helices]], [[Sheets in Proteins\|β-sheets]] and [[Turns in Proteins\|turns]] are three important types of secondary structures. Turns are classified as a secondary structure even though their structures are ordered but not repetitive. The tertiary structure is the overall 3D structure of a globular protein and is produced by folding the helices and sheets upon themselves with turns and [[Loops in Proteins\|loops]] forming the folds. Non-covalent molecular attractions are important forces in maintaining the folded conformation of a globular protein. For the most part, these attractions are between the atoms of the side chains but can be between the side chains and a bound ligand. Hydrogen bonds between back bone atoms are important in maintaining secondary structures, and those between side chains are involved in maintaining the tertiary structure. Examples of finding and visualizing both types in globular proteins are at [[Hydrogen bonds \|hydrogen bonds]]. The attractive forces of [[Salt_bridges \|salt bridges]] are important in maintaining some tertiary structures, but they also can be involved in the binding of ligands. The Disulfide bond is the one type of covalent bond that can play an important role in maintaining the tertiary structure as well as connecting two or more peptide chains together. Links to sites having structures that illustrate disulfide bonds are at [[Cystine]]. Some globular proteins have a quaternary structure, and it is formed when two or more globular protein molecules (monomer) join together and form a multimeric unit. [[Hemoglobin]] is a good example of a protein that has a quarternary structure.

Alexander Berchansky at 10:00, 21 August 2013

Alexander Berchansky — Wed, 21 Aug 2013 10:00:10 GMT

←Older revision		Revision as of 10:00, 21 August 2013
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		+	<StructureSection load='1a7v' size='500' frame='true' align='right' scene ='Globular_Proteins/Two_layers/3' caption='' >__NOTOC__
	Globular proteins have a 3D molecular structure that has a shape that is anywhere from a sphere to a cigar. Usually the structure of a globular protein is divided into three or four levels. The primary structure is simply the sequence of amino acids forming the peptide chain. The peptide chain can be folded in an ordered and repetitive fashion, and the structures with ordered and repetitive conformations are called [[Secondary_structure\|secondary structures]]. [[Helices_in_Proteins\|Helices]], [[Sheets in Proteins\|β-sheets]] and [[Turns in Proteins\|turns]] are three important types of secondary structures. Turns are classified as a secondary structure even though their structures are ordered but not repetitive. The tertiary structure is the overall 3D structure of a globular protein and is produced by folding the helices and sheets upon themselves with turns and [[Loops in Proteins\|loops]] forming the folds. Non-covalent molecular attractions are important forces in maintaining the folded conformation of a globular protein. For the most part, these attractions are between the atoms of the side chains but can be between the side chains and a bound ligand. Hydrogen bonds between back bone atoms are important in maintaining secondary structures, and those between side chains are involved in maintaining the tertiary structure. Examples of finding and visualizing both types in globular proteins are at [[Hydrogen bonds \|hydrogen bonds]]. The attractive forces of [[Salt_bridges \|salt bridges]] are important in maintaining some tertiary structures, but they also can be involved in the binding of ligands. The Disulfide bond is the one type of covalent bond that can play an important role in maintaining the tertiary structure as well as connecting two or more peptide chains together. Links to sites having structures that illustrate disulfide bonds are at [[Cystine]]. Some globular proteins have a quaternary structure, and it is formed when two or more globular protein molecules (monomer) join together and form a multimeric unit. [[Hemoglobin]] is a good example of a protein that has a quarternary structure.		Globular proteins have a 3D molecular structure that has a shape that is anywhere from a sphere to a cigar. Usually the structure of a globular protein is divided into three or four levels. The primary structure is simply the sequence of amino acids forming the peptide chain. The peptide chain can be folded in an ordered and repetitive fashion, and the structures with ordered and repetitive conformations are called [[Secondary_structure\|secondary structures]]. [[Helices_in_Proteins\|Helices]], [[Sheets in Proteins\|β-sheets]] and [[Turns in Proteins\|turns]] are three important types of secondary structures. Turns are classified as a secondary structure even though their structures are ordered but not repetitive. The tertiary structure is the overall 3D structure of a globular protein and is produced by folding the helices and sheets upon themselves with turns and [[Loops in Proteins\|loops]] forming the folds. Non-covalent molecular attractions are important forces in maintaining the folded conformation of a globular protein. For the most part, these attractions are between the atoms of the side chains but can be between the side chains and a bound ligand. Hydrogen bonds between back bone atoms are important in maintaining secondary structures, and those between side chains are involved in maintaining the tertiary structure. Examples of finding and visualizing both types in globular proteins are at [[Hydrogen bonds \|hydrogen bonds]]. The attractive forces of [[Salt_bridges \|salt bridges]] are important in maintaining some tertiary structures, but they also can be involved in the binding of ligands. The Disulfide bond is the one type of covalent bond that can play an important role in maintaining the tertiary structure as well as connecting two or more peptide chains together. Links to sites having structures that illustrate disulfide bonds are at [[Cystine]]. Some globular proteins have a quaternary structure, and it is formed when two or more globular protein molecules (monomer) join together and form a multimeric unit. [[Hemoglobin]] is a good example of a protein that has a quarternary structure.

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	Layers of backbone in the core of the structure is a feature that many, but not all, globular proteins have. The number of layers and their location vary for different proteins, but in all of these proteins the hydrophobic forces between the layers play a major role in maintaining the tertiary structure.		Layers of backbone in the core of the structure is a feature that many, but not all, globular proteins have. The number of layers and their location vary for different proteins, but in all of these proteins the hydrophobic forces between the layers play a major role in maintaining the tertiary structure.
-	~~<StructureSection load='1a7v' size='500' frame='true' align='right' scene ='Globular_Proteins/Two_layers/3' caption='' >__NOTOC__~~	+
	=== Two Layers ===		=== Two Layers ===
	The ribbons representing the backbones show the two layers of α-helices. The <scene name='Globular_Proteins/Two_layers_phobic/1'>hydrophobic side chains</scene> are shown in ball and stick with one layer colored green and the other cyan. Notice that these side chains are mostly located between the layers and that few are on the exterior of the molecule. View the <scene name='Globular_Proteins/Two_layers_vdw_contact/1'>points of hydrophobic attraction</scene> between the two layers. The <scene name='Globular_Proteins/Two_layers_hbond_contact/2'>hydrogen bonds</scene> between the layers are only on the edges. The <scene name='Globular_Proteins/Two_layers_polar/1'>polar residues</scene> are now ball & stick, and they tend to be on the surface of the molecule where they can associate with <scene name='Globular_Proteins/Two_layers_water/1'>water</scene>. More clearly see polar groups on the surface by <scene name='Globular_Proteins/Two_layers_polar_rot/1'>rotating structure</scene> so that axis of helix aligns with z-axis, compare this scene with a similarly aligned display of the hydrophobic side chains.		The ribbons representing the backbones show the two layers of α-helices. The <scene name='Globular_Proteins/Two_layers_phobic/1'>hydrophobic side chains</scene> are shown in ball and stick with one layer colored green and the other cyan. Notice that these side chains are mostly located between the layers and that few are on the exterior of the molecule. View the <scene name='Globular_Proteins/Two_layers_vdw_contact/1'>points of hydrophobic attraction</scene> between the two layers. The <scene name='Globular_Proteins/Two_layers_hbond_contact/2'>hydrogen bonds</scene> between the layers are only on the edges. The <scene name='Globular_Proteins/Two_layers_polar/1'>polar residues</scene> are now ball & stick, and they tend to be on the surface of the molecule where they can associate with <scene name='Globular_Proteins/Two_layers_water/1'>water</scene>. More clearly see polar groups on the surface by <scene name='Globular_Proteins/Two_layers_polar_rot/1'>rotating structure</scene> so that axis of helix aligns with z-axis, compare this scene with a similarly aligned display of the hydrophobic side chains.
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	* <scene name='Globular_Proteins/Horseshoe/1'>Porcine ribonuclease inhibitor</scene> - contains leucine-rich repeats.		* <scene name='Globular_Proteins/Horseshoe/1'>Porcine ribonuclease inhibitor</scene> - contains leucine-rich repeats.

-
-	</StructureSection>
	<table width='500' align='right' cellpadding='10'><tr><td bgcolor='#eeeeee'><center>'''Tertiary Structures of Examples'''<scene name='Globular_Proteins/Two_layers/2'> (Initial scene)</scene></center></td></tr></table>		<table width='500' align='right' cellpadding='10'><tr><td bgcolor='#eeeeee'><center>'''Tertiary Structures of Examples'''<scene name='Globular_Proteins/Two_layers/2'> (Initial scene)</scene></center></td></tr></table>
	{{Clear}}		{{Clear}}
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	Some proteins or peptide segments are [[Intrinsically_Disordered_Protein \|intrinsically disordered]] (unstructured). Whether a complete protein or a protein segment since they are disordered, they can not be crystallized for x-ray crystallographic study. However, when these peptides or peptide segments bind to other proteins they become ordered segments, and can be crystallized along with the binding protein for x-ray crystallographic study. When these peptides bind to other proteins, since their conformations are extended and not compact, the binding occurs over relatively large surface areas of the binding proteins. Examples given below illustrate the extended conformations of the peptide segments as well as the large binding surface. When viewing the unstructured peptides as unbound segments, realize that the conformation which is being displayed is not a disordered conformation but is the conformation of the bound segments with the structure of the binding protein being hidden. If the peptides or peptide fragments were actually free and unbound, since they are unordered, the individual molecules would have a range of conformations and not just one.		Some proteins or peptide segments are [[Intrinsically_Disordered_Protein \|intrinsically disordered]] (unstructured). Whether a complete protein or a protein segment since they are disordered, they can not be crystallized for x-ray crystallographic study. However, when these peptides or peptide segments bind to other proteins they become ordered segments, and can be crystallized along with the binding protein for x-ray crystallographic study. When these peptides bind to other proteins, since their conformations are extended and not compact, the binding occurs over relatively large surface areas of the binding proteins. Examples given below illustrate the extended conformations of the peptide segments as well as the large binding surface. When viewing the unstructured peptides as unbound segments, realize that the conformation which is being displayed is not a disordered conformation but is the conformation of the bound segments with the structure of the binding protein being hidden. If the peptides or peptide fragments were actually free and unbound, since they are unordered, the individual molecules would have a range of conformations and not just one.
-	<StructureSection load='2ben' size='500' side='right' caption='' scene='Globular_Proteins/Insulin1/1'>__NOTOC__

	=== Disulfide-Rich Proteins ===		=== Disulfide-Rich Proteins ===

Karl Oberholser at 19:55, 6 November 2012

Karl Oberholser — Tue, 06 Nov 2012 19:55:53 GMT

←Older revision		Revision as of 19:55, 6 November 2012
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	Layers of backbone in the core of the structure is a feature that many, but not all, globular proteins have. The number of layers and their location vary for different proteins, but in all of these proteins the hydrophobic forces between the layers play a major role in maintaining the tertiary structure.		Layers of backbone in the core of the structure is a feature that many, but not all, globular proteins have. The number of layers and their location vary for different proteins, but in all of these proteins the hydrophobic forces between the layers play a major role in maintaining the tertiary structure.
-	<StructureSection load='1a7v' size='500' frame='true' align='right' scene ='Globular_Proteins/Two_layers/2' caption='' >__NOTOC__	+	<StructureSection load='1a7v' size='500' frame='true' align='right' scene ='Globular_Proteins/Two_layers/3' caption='' >__NOTOC__
	=== Two Layers ===		=== Two Layers ===
-	The ribbons representing the backbones show the two layers of α-helices. The <scene name='Globular_Proteins/Two_layers_phobic/1'>hydrophobic side chains</scene> are shown in ball and stick with one layer colored green and the other cyan. Notice that these side chains are mostly located between the layers and that few are on the exterior of the molecule. View the <scene name='Globular_Proteins/Two_layers_vdw_contact/1'>points of hydrophobic attraction</scene> between the two layers. The <scene name='Globular_Proteins/Two_layers_hbond_contact/1'>hydrogen bonds</scene> between the layers are only on the edges. The <scene name='Globular_Proteins/Two_layers_polar/1'>polar residues</scene> are now ball & stick, and they tend to be on the surface of the molecule where they can associate with <scene name='Globular_Proteins/Two_layers_water/1'>water</scene>. More clearly see polar groups on the surface by <scene name='Globular_Proteins/Two_layers_polar_rot/1'>rotating structure</scene> so that axis of helix aligns with z-axis, compare this scene with a similarly aligned display of the hydrophobic side chains.	+	The ribbons representing the backbones show the two layers of α-helices. The <scene name='Globular_Proteins/Two_layers_phobic/1'>hydrophobic side chains</scene> are shown in ball and stick with one layer colored green and the other cyan. Notice that these side chains are mostly located between the layers and that few are on the exterior of the molecule. View the <scene name='Globular_Proteins/Two_layers_vdw_contact/1'>points of hydrophobic attraction</scene> between the two layers. The <scene name='Globular_Proteins/Two_layers_hbond_contact/2'>hydrogen bonds</scene> between the layers are only on the edges. The <scene name='Globular_Proteins/Two_layers_polar/1'>polar residues</scene> are now ball & stick, and they tend to be on the surface of the molecule where they can associate with <scene name='Globular_Proteins/Two_layers_water/1'>water</scene>. More clearly see polar groups on the surface by <scene name='Globular_Proteins/Two_layers_polar_rot/1'>rotating structure</scene> so that axis of helix aligns with z-axis, compare this scene with a similarly aligned display of the hydrophobic side chains.

	=== Three Layers ===		=== Three Layers ===

Karl Oberholser at 19:16, 6 November 2012

Karl Oberholser — Tue, 06 Nov 2012 19:16:05 GMT

←Older revision		Revision as of 19:16, 6 November 2012
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	<StructureSection load='1a7v' size='500' frame='true' align='right' scene ='Globular_Proteins/Two_layers/2' caption='' >__NOTOC__		<StructureSection load='1a7v' size='500' frame='true' align='right' scene ='Globular_Proteins/Two_layers/2' caption='' >__NOTOC__
	=== Two Layers ===		=== Two Layers ===
-	The ribbons representing the backbones show the two layers of α-helices. The <scene name='Globular_Proteins/Two_layers_phobic/1'>hydrophobic side chains</scene> are shown in ball and stick with one layer colored green and the other cyan. Notice that these side chains are mostly located between the layers and that few are on the exterior of the molecule. The <scene name='Globular_Proteins/Two_layers_polar/1'>polar residues</scene> are now ball & stick, and they tend to be on the surface of the molecule where they can associate with <scene name='Globular_Proteins/Two_layers_water/1'>water</scene>. More clearly see polar groups on the surface by <scene name='Globular_Proteins/Two_layers_polar_rot/1'>rotating structure</scene> so that axis of helix aligns with z-axis, compare this scene with a similarly aligned display of the hydrophobic side chains.	+	The ribbons representing the backbones show the two layers of α-helices. The <scene name='Globular_Proteins/Two_layers_phobic/1'>hydrophobic side chains</scene> are shown in ball and stick with one layer colored green and the other cyan. Notice that these side chains are mostly located between the layers and that few are on the exterior of the molecule. View the <scene name='Globular_Proteins/Two_layers_vdw_contact/1'>points of hydrophobic attraction</scene> between the two layers. The <scene name='Globular_Proteins/Two_layers_hbond_contact/1'>hydrogen bonds</scene> between the layers are only on the edges. The <scene name='Globular_Proteins/Two_layers_polar/1'>polar residues</scene> are now ball & stick, and they tend to be on the surface of the molecule where they can associate with <scene name='Globular_Proteins/Two_layers_water/1'>water</scene>. More clearly see polar groups on the surface by <scene name='Globular_Proteins/Two_layers_polar_rot/1'>rotating structure</scene> so that axis of helix aligns with z-axis, compare this scene with a similarly aligned display of the hydrophobic side chains.

	=== Three Layers ===		=== Three Layers ===

Karl Oberholser at 16:51, 27 June 2011

Karl Oberholser — Mon, 27 Jun 2011 16:51:48 GMT

←Older revision		Revision as of 16:51, 27 June 2011
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-	Globular proteins have a 3D molecular structure that has a shape that is anywhere from a sphere to a cigar. Usually the structure of a globular protein is divided into three or four levels. The primary structure is simply the sequence of amino acids forming the peptide chain. The peptide chain can be folded in an ordered and repetitive fashion, and the structures with ordered and repetitive conformations are called [[Secondary_structure\|secondary structures]]. [[Helices_in_Proteins\|Helices]], [[Sheets in Proteins\|β-sheets]] and [[Turns in Proteins\|turns]] are three important types of secondary structures. Turns are classified as a secondary structure even though their structures are ordered but not repetitive. The tertiary structure is the overall 3D structure of a globular protein and is produced by folding the helices and sheets upon themselves with turns and [[Loops in Proteins\|loops]] forming the folds. Non-covalent molecular attractions are important forces in maintaining the folded conformation of a globular protein. For the most part, these attractions are between the atoms of the side chains but can be between the side chains and a bound ligand. Hydrogen bonds between back bone atoms are important in maintaining secondary structures, and those between side chains are involved in maintaining the tertiary structure. Examples of finding and visualizing both types in globular proteins are at [[Hydrogen bonds \|hydrogen bonds]]. The attractive forces of [[Salt_bridges \|salt bridges]] are important in maintaining some tertiary structures, but they also can be involved in the binding of ligands. The Disulfide bond is the one type of covalent bond that can play an important role in maintaining the tertiary structure as well as connecting two or more peptide chains together. Links to structures that illustrate disulfide bonds are at [[Cystine]]. Some globular proteins have a quaternary structure, and it is formed when two or more globular protein molecules (monomer) join together and form a multimeric unit. [[Hemoglobin]] is a good example of a protein that has a quarternary structure.	+	Globular proteins have a 3D molecular structure that has a shape that is anywhere from a sphere to a cigar. Usually the structure of a globular protein is divided into three or four levels. The primary structure is simply the sequence of amino acids forming the peptide chain. The peptide chain can be folded in an ordered and repetitive fashion, and the structures with ordered and repetitive conformations are called [[Secondary_structure\|secondary structures]]. [[Helices_in_Proteins\|Helices]], [[Sheets in Proteins\|β-sheets]] and [[Turns in Proteins\|turns]] are three important types of secondary structures. Turns are classified as a secondary structure even though their structures are ordered but not repetitive. The tertiary structure is the overall 3D structure of a globular protein and is produced by folding the helices and sheets upon themselves with turns and [[Loops in Proteins\|loops]] forming the folds. Non-covalent molecular attractions are important forces in maintaining the folded conformation of a globular protein. For the most part, these attractions are between the atoms of the side chains but can be between the side chains and a bound ligand. Hydrogen bonds between back bone atoms are important in maintaining secondary structures, and those between side chains are involved in maintaining the tertiary structure. Examples of finding and visualizing both types in globular proteins are at [[Hydrogen bonds \|hydrogen bonds]]. The attractive forces of [[Salt_bridges \|salt bridges]] are important in maintaining some tertiary structures, but they also can be involved in the binding of ligands. The Disulfide bond is the one type of covalent bond that can play an important role in maintaining the tertiary structure as well as connecting two or more peptide chains together. Links to sites having structures that illustrate disulfide bonds are at [[Cystine]]. Some globular proteins have a quaternary structure, and it is formed when two or more globular protein molecules (monomer) join together and form a multimeric unit. [[Hemoglobin]] is a good example of a protein that has a quarternary structure.

	The tertiary structure of many globular proteins can be characterized by the number of layers of peptide backbone which are present and the attractive forces which are generated by these layers.<ref name='Garret'>Biochemistry, 4th ed., R. H. Garrett & C. M. Grisham, Thomson/Brooks/Cole, pages 167-170.</ref> Other important characteristics in the absence of backbone layers are the presence of disulfice bonds, of chelated metal ions or of intrinsically unstructured segments <ref name='Garret'/>. The objective of this page is to introduce the tertiary structures of globular proteins by illustrating these characteristics of globular proteins.		The tertiary structure of many globular proteins can be characterized by the number of layers of peptide backbone which are present and the attractive forces which are generated by these layers.<ref name='Garret'>Biochemistry, 4th ed., R. H. Garrett & C. M. Grisham, Thomson/Brooks/Cole, pages 167-170.</ref> Other important characteristics in the absence of backbone layers are the presence of disulfice bonds, of chelated metal ions or of intrinsically unstructured segments <ref name='Garret'/>. The objective of this page is to introduce the tertiary structures of globular proteins by illustrating these characteristics of globular proteins.

Karl Oberholser at 22:22, 25 June 2011

Karl Oberholser — Sat, 25 Jun 2011 22:22:25 GMT

←Older revision		Revision as of 22:22, 25 June 2011
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-	Globular proteins have a 3D molecular structure that has a shape that is anywhere from a sphere to a cigar. Usually the structure of a globular protein is divided into three or four levels. The primary structure is simply the sequence of amino acids forming the peptide chain. The peptide chain can be folded in an ordered and repetitive fashion, and the structures with ordered and repetitive conformations are called [[Secondary_structure\|secondary structures]]. [[Helices_in_Proteins\|Helices]], [[Sheets in Proteins\|β-sheets]] and [[Turns in Proteins\|turns]] are three important types of secondary structures. Turns are classified as a secondary structure even though their structures are ordered but not repetitive. The tertiary structure is the overall 3D structure of a globular protein and is produced by folding the helices and sheets upon themselves with turns and [[Loops in Proteins\|loops]] forming the folds. Non-covalent molecular attractions are important forces in maintaining the folded conformation of a globular protein. For the most part, these attractions are between the atoms of the side chains but can be between the side chains and a bound ligand. Hydrogen bonds between back bone atoms are important in maintaining secondary structures, and those between side chains are involved in maintaining the tertiary structure. Examples of finding and visualizing both types in globular proteins are at [[Hydrogen bonds \|hydrogen bonds]]. The attractive forces of [[Salt_bridges \|salt bridges]] are important in maintaining some tertiary structures, but they also can be involved in the binding of ligands. The Disulfide bond is the one type of covalent bond that can play an important role in maintaining the tertiary structure as well as connecting two or more peptide chains together. Links to structures that illustrate disulfide bonds are at [[Cystine]].	+	Globular proteins have a 3D molecular structure that has a shape that is anywhere from a sphere to a cigar. Usually the structure of a globular protein is divided into three or four levels. The primary structure is simply the sequence of amino acids forming the peptide chain. The peptide chain can be folded in an ordered and repetitive fashion, and the structures with ordered and repetitive conformations are called [[Secondary_structure\|secondary structures]]. [[Helices_in_Proteins\|Helices]], [[Sheets in Proteins\|β-sheets]] and [[Turns in Proteins\|turns]] are three important types of secondary structures. Turns are classified as a secondary structure even though their structures are ordered but not repetitive. The tertiary structure is the overall 3D structure of a globular protein and is produced by folding the helices and sheets upon themselves with turns and [[Loops in Proteins\|loops]] forming the folds. Non-covalent molecular attractions are important forces in maintaining the folded conformation of a globular protein. For the most part, these attractions are between the atoms of the side chains but can be between the side chains and a bound ligand. Hydrogen bonds between back bone atoms are important in maintaining secondary structures, and those between side chains are involved in maintaining the tertiary structure. Examples of finding and visualizing both types in globular proteins are at [[Hydrogen bonds \|hydrogen bonds]]. The attractive forces of [[Salt_bridges \|salt bridges]] are important in maintaining some tertiary structures, but they also can be involved in the binding of ligands. The Disulfide bond is the one type of covalent bond that can play an important role in maintaining the tertiary structure as well as connecting two or more peptide chains together. Links to structures that illustrate disulfide bonds are at [[Cystine]]. Some globular proteins have a quaternary structure, and it is formed when two or more globular protein molecules (monomer) join together and form a multimeric unit. [[Hemoglobin]] is a good example of a protein that has a quarternary structure.

-	Some globular proteins have a quaternary structure, and it is formed when two or more globular protein molecules (monomer) join together and form a multimeric unit. [[Hemoglobin]] is a good example of a protein that has a quarternary structure. The tertiary structure of many globular proteins can be characterized by the number of layers of peptide backbone which are present and the attractive forces which are generated by these layers.<ref name='Garret'>Biochemistry, 4th ed., R. H. Garrett & C. M. Grisham, Thomson/Brooks/Cole, pages 167-170.</ref> Other important characteristics in the absence of backbone layers are the presence of disulfice bonds, of chelated metal ions or of intrinsically unstructured segments <ref name='Garret'/>. The objective of this page is to introduce the tertiary structures of globular proteins by illustrating these characteristics of globular proteins.	+	The tertiary structure of many globular proteins can be characterized by the number of layers of peptide backbone which are present and the attractive forces which are generated by these layers.<ref name='Garret'>Biochemistry, 4th ed., R. H. Garrett & C. M. Grisham, Thomson/Brooks/Cole, pages 167-170.</ref> Other important characteristics in the absence of backbone layers are the presence of disulfice bonds, of chelated metal ions or of intrinsically unstructured segments <ref name='Garret'/>. The objective of this page is to introduce the tertiary structures of globular proteins by illustrating these characteristics of globular proteins.

	== Layers of Backbone Present in the Structure ==		== Layers of Backbone Present in the Structure ==

Karl Oberholser at 22:20, 25 June 2011

Karl Oberholser — Sat, 25 Jun 2011 22:20:08 GMT

←Older revision		Revision as of 22:20, 25 June 2011
Line 1:		Line 1:
-	Globular proteins have a 3D molecular structure that has a shape that is anywhere from a sphere to a cigar. Usually the structure of a globular protein is divided into three or four levels. The primary structure is simply the sequence of amino acids forming the peptide chain. The peptide chain can be folded in an ordered and repetitive fashion, and the structures with ordered and repetitive conformations are called [[Secondary_structure\|secondary structures]]. [[Helices_in_Proteins\|Helices]], [[Sheets in Proteins\|β-sheets]] and [[Turns in Proteins\|turns]] are three important types of secondary structures. Turns are classified as a secondary structure even though their structures are ordered but not repetitive. The tertiary structure is the overall 3D structure of a globular protein and is produced by folding the helices and sheets upon themselves with turns and [[Loops in Proteins\|loops]] forming the folds. Non-covalent molecular attractions are important forces in maintaining the folded conformation of a globular protein. For the most part, these attractions are between the atoms of the side chains but can be between the side chains and a bound ligand. Hydrogen bonds between back bone atoms are important in maintaining secondary structures, and those between side chains are involved in maintaining the tertiary structure. Examples of finding and visualizing both types in globular proteins are at [[Hydrogen bonds \|hydrogen bonds]]. The attractive forces of [[Salt_bridges \|salt bridges]] are important in maintaining some tertiary structures, but they also can be involved in the binding of ligands. The Disulfide bond is the one covalent bond that can play an important role in maintaining the tertiary structure as well as connecting two or more peptide chains together. Links to structures that illustrate disulfide bonds are at [[Cystine]].	+	Globular proteins have a 3D molecular structure that has a shape that is anywhere from a sphere to a cigar. Usually the structure of a globular protein is divided into three or four levels. The primary structure is simply the sequence of amino acids forming the peptide chain. The peptide chain can be folded in an ordered and repetitive fashion, and the structures with ordered and repetitive conformations are called [[Secondary_structure\|secondary structures]]. [[Helices_in_Proteins\|Helices]], [[Sheets in Proteins\|β-sheets]] and [[Turns in Proteins\|turns]] are three important types of secondary structures. Turns are classified as a secondary structure even though their structures are ordered but not repetitive. The tertiary structure is the overall 3D structure of a globular protein and is produced by folding the helices and sheets upon themselves with turns and [[Loops in Proteins\|loops]] forming the folds. Non-covalent molecular attractions are important forces in maintaining the folded conformation of a globular protein. For the most part, these attractions are between the atoms of the side chains but can be between the side chains and a bound ligand. Hydrogen bonds between back bone atoms are important in maintaining secondary structures, and those between side chains are involved in maintaining the tertiary structure. Examples of finding and visualizing both types in globular proteins are at [[Hydrogen bonds \|hydrogen bonds]]. The attractive forces of [[Salt_bridges \|salt bridges]] are important in maintaining some tertiary structures, but they also can be involved in the binding of ligands. The Disulfide bond is the one type of covalent bond that can play an important role in maintaining the tertiary structure as well as connecting two or more peptide chains together. Links to structures that illustrate disulfide bonds are at [[Cystine]].

	Some globular proteins have a quaternary structure, and it is formed when two or more globular protein molecules (monomer) join together and form a multimeric unit. [[Hemoglobin]] is a good example of a protein that has a quarternary structure. The tertiary structure of many globular proteins can be characterized by the number of layers of peptide backbone which are present and the attractive forces which are generated by these layers.<ref name='Garret'>Biochemistry, 4th ed., R. H. Garrett & C. M. Grisham, Thomson/Brooks/Cole, pages 167-170.</ref> Other important characteristics in the absence of backbone layers are the presence of disulfice bonds, of chelated metal ions or of intrinsically unstructured segments <ref name='Garret'/>. The objective of this page is to introduce the tertiary structures of globular proteins by illustrating these characteristics of globular proteins.		Some globular proteins have a quaternary structure, and it is formed when two or more globular protein molecules (monomer) join together and form a multimeric unit. [[Hemoglobin]] is a good example of a protein that has a quarternary structure. The tertiary structure of many globular proteins can be characterized by the number of layers of peptide backbone which are present and the attractive forces which are generated by these layers.<ref name='Garret'>Biochemistry, 4th ed., R. H. Garrett & C. M. Grisham, Thomson/Brooks/Cole, pages 167-170.</ref> Other important characteristics in the absence of backbone layers are the presence of disulfice bonds, of chelated metal ions or of intrinsically unstructured segments <ref name='Garret'/>. The objective of this page is to introduce the tertiary structures of globular proteins by illustrating these characteristics of globular proteins.

Karl Oberholser at 21:31, 25 June 2011

Karl Oberholser — Sat, 25 Jun 2011 21:31:09 GMT

←Older revision		Revision as of 21:31, 25 June 2011
Line 1:		Line 1:
-	Globular proteins have a 3D molecular structure that has a shape that is anywhere from a sphere to a cigar. Usually the structure of a globular protein is divided into three or four levels. The primary structure is simply the sequence of amino acids forming the peptide chain. The peptide chain can be folded in an ordered and repetitive fashion, and the structures with ordered and repetitive conformations are called [[Secondary_structure\|secondary structures]]. [[Helices_in_Proteins\|Helices]], [[Sheets in Proteins\|β-sheets]] and [[Turns in Proteins\|turns]] are three important types of secondary structures. Turns are classified as a secondary structure even though their structures are ordered but not repetitive. The tertiary structure is the overall 3D structure of a globular protein and is produced by folding the helices and sheets upon themselves with turns and [[Loops in Proteins\|loops]] forming the folds. Non-covalent molecular attractions are important forces in maintaining the folded conformation of a globular protein. For the most part, these attractions are between the atoms of the side chains but can be between the side chains and a bound ligand. Hydrogen bonds between back bone atoms are important in maintaining secondary structures, and those between side chains are involved in maintaining the tertiary structure. Examples of finding and visualizing both types in globular proteins are at [[Hydrogen bonds \|hydrogen bonds]]. The attractive forces of [[Salt_bridges \|salt bridges]] are important in maintaining some tertiary structures, but they also can be involved in the binding of ligands. The Disulfide bond is the one covalent bond that can play an important role in maintaining the tertiary structure as well as connecting two or more peptide chains together. Links to structures that illustrate disulfide bonds are at [[Cystine]]. Some globular proteins have a quaternary structure, and it is formed when two or more globular protein molecules (monomer) join together and form a multimeric unit. [[Hemoglobin]] is a good example of a protein that has a quarternary structure. The tertiary structure of many globular proteins can be characterized by the number of layers of peptide backbone which are present and the attractive forces which are generated by these layers.<ref name='Garret'>Biochemistry, 4th ed., R. H. Garrett & C. M. Grisham, Thomson/Brooks/Cole, pages 167-170.</ref> Other important characteristics in the absence of backbone layers are the presence of disulfice bonds, of chelated metal ions or of intrinsically unstructured segments <ref name='Garret'/>. The objective of this page is to introduce the tertiary structures of globular proteins by illustrating these characteristics of globular proteins.	+	Globular proteins have a 3D molecular structure that has a shape that is anywhere from a sphere to a cigar. Usually the structure of a globular protein is divided into three or four levels. The primary structure is simply the sequence of amino acids forming the peptide chain. The peptide chain can be folded in an ordered and repetitive fashion, and the structures with ordered and repetitive conformations are called [[Secondary_structure\|secondary structures]]. [[Helices_in_Proteins\|Helices]], [[Sheets in Proteins\|β-sheets]] and [[Turns in Proteins\|turns]] are three important types of secondary structures. Turns are classified as a secondary structure even though their structures are ordered but not repetitive. The tertiary structure is the overall 3D structure of a globular protein and is produced by folding the helices and sheets upon themselves with turns and [[Loops in Proteins\|loops]] forming the folds. Non-covalent molecular attractions are important forces in maintaining the folded conformation of a globular protein. For the most part, these attractions are between the atoms of the side chains but can be between the side chains and a bound ligand. Hydrogen bonds between back bone atoms are important in maintaining secondary structures, and those between side chains are involved in maintaining the tertiary structure. Examples of finding and visualizing both types in globular proteins are at [[Hydrogen bonds \|hydrogen bonds]]. The attractive forces of [[Salt_bridges \|salt bridges]] are important in maintaining some tertiary structures, but they also can be involved in the binding of ligands. The Disulfide bond is the one covalent bond that can play an important role in maintaining the tertiary structure as well as connecting two or more peptide chains together. Links to structures that illustrate disulfide bonds are at [[Cystine]].
		+
		+	Some globular proteins have a quaternary structure, and it is formed when two or more globular protein molecules (monomer) join together and form a multimeric unit. [[Hemoglobin]] is a good example of a protein that has a quarternary structure. The tertiary structure of many globular proteins can be characterized by the number of layers of peptide backbone which are present and the attractive forces which are generated by these layers.<ref name='Garret'>Biochemistry, 4th ed., R. H. Garrett & C. M. Grisham, Thomson/Brooks/Cole, pages 167-170.</ref> Other important characteristics in the absence of backbone layers are the presence of disulfice bonds, of chelated metal ions or of intrinsically unstructured segments <ref name='Garret'/>. The objective of this page is to introduce the tertiary structures of globular proteins by illustrating these characteristics of globular proteins.

	== Layers of Backbone Present in the Structure ==		== Layers of Backbone Present in the Structure ==

Karl Oberholser at 21:29, 25 June 2011

Karl Oberholser — Sat, 25 Jun 2011 21:29:39 GMT

←Older revision		Revision as of 21:29, 25 June 2011
Line 1:		Line 1:
-	Globular proteins have a 3D molecular structure that has a shape that is anywhere from a sphere to a cigar. Usually the structure of a globular protein is divided into three or four levels. The primary structure is simply the sequence of amino acids forming the peptide chain. The peptide chain can be folded in an ordered and repetitive fashion, and the structures with ordered and repetitive conformations are called [[Secondary_structure\|secondary structures]]. [[Helices_in_Proteins\|Helices]], [[Sheets in Proteins\|β-sheets]] and [[Turns in Proteins\|turns]] are three important types of secondary structures. Turns are classified as a secondary structure even though their structures are ordered but not repetitive. The tertiary structure is the overall 3D structure of a globular protein and is produced by folding the helices and sheets upon themselves with turns and [[Loops in Proteins\|loops]] forming the folds. Non-covalent molecular attractions are important forces in maintaining the folded conformation of a globular protein. For the most part, these attractions are between the atoms of the side chains but can be between the side chains and a bound ligand. Hydrogen bonds between back bone atoms are important in maintaining secondary structures, and those between side chains are involved in maintaining the tertiary structure. Examples of finding and visualizing both types in globular proteins are at [[Hydrogen bonds \|hydrogen bonds]]. The attractive forces of [[Salt_bridges \|salt bridges]] are important in maintaining some tertiary structures, but they also can be involved in the binding of ligands. Some globular proteins have a quaternary structure, and it is formed when two or more globular protein molecules (monomer) join together and form a multimeric unit. [[Hemoglobin]] is a good example of a protein that has a quarternary structure. The tertiary structure of many globular proteins can be characterized by the number of layers of peptide backbone which are present and the attractive forces which are generated by these layers.<ref name='Garret'>Biochemistry, 4th ed., R. H. Garrett & C. M. Grisham, Thomson/Brooks/Cole, pages 167-170.</ref> Other important characteristics in the absence of backbone layers are the presence of disulfice bonds, of chelated metal ions or of intrinsically unstructured segments <ref name='Garret'/>. The objective of this page is to introduce the tertiary structures of globular proteins by illustrating these characteristics of globular proteins.	+	Globular proteins have a 3D molecular structure that has a shape that is anywhere from a sphere to a cigar. Usually the structure of a globular protein is divided into three or four levels. The primary structure is simply the sequence of amino acids forming the peptide chain. The peptide chain can be folded in an ordered and repetitive fashion, and the structures with ordered and repetitive conformations are called [[Secondary_structure\|secondary structures]]. [[Helices_in_Proteins\|Helices]], [[Sheets in Proteins\|β-sheets]] and [[Turns in Proteins\|turns]] are three important types of secondary structures. Turns are classified as a secondary structure even though their structures are ordered but not repetitive. The tertiary structure is the overall 3D structure of a globular protein and is produced by folding the helices and sheets upon themselves with turns and [[Loops in Proteins\|loops]] forming the folds. Non-covalent molecular attractions are important forces in maintaining the folded conformation of a globular protein. For the most part, these attractions are between the atoms of the side chains but can be between the side chains and a bound ligand. Hydrogen bonds between back bone atoms are important in maintaining secondary structures, and those between side chains are involved in maintaining the tertiary structure. Examples of finding and visualizing both types in globular proteins are at [[Hydrogen bonds \|hydrogen bonds]]. The attractive forces of [[Salt_bridges \|salt bridges]] are important in maintaining some tertiary structures, but they also can be involved in the binding of ligands. The Disulfide bond is the one covalent bond that can play an important role in maintaining the tertiary structure as well as connecting two or more peptide chains together. Links to structures that illustrate disulfide bonds are at [[Cystine]]. Some globular proteins have a quaternary structure, and it is formed when two or more globular protein molecules (monomer) join together and form a multimeric unit. [[Hemoglobin]] is a good example of a protein that has a quarternary structure. The tertiary structure of many globular proteins can be characterized by the number of layers of peptide backbone which are present and the attractive forces which are generated by these layers.<ref name='Garret'>Biochemistry, 4th ed., R. H. Garrett & C. M. Grisham, Thomson/Brooks/Cole, pages 167-170.</ref> Other important characteristics in the absence of backbone layers are the presence of disulfice bonds, of chelated metal ions or of intrinsically unstructured segments <ref name='Garret'/>. The objective of this page is to introduce the tertiary structures of globular proteins by illustrating these characteristics of globular proteins.

	== Layers of Backbone Present in the Structure ==		== Layers of Backbone Present in the Structure ==