Sheets in Proteins
From Proteopedia
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A β-pleated sheet contains multiple peptide strands that are positioned adjacent to one another (such as the one <scene name='Sheets_in_Proteins/Syn sheet1/2'>shown</scene> on the right). The planes of the <scene name='Sheets_in_Proteins/Syn_sheet2/2'>pleats</scene> are formed by the planes of the peptide bond. The alpha carbons of the peptide chain are at the valleys and peaks of the pleats. The peptides are <scene name='Sheets_in_Proteins/Syn_sheet3/3'>rainbow colored</scene> (blue amino end changing to red carboxy end) to show that the adjacent peptides are running in opposite directions making the sheet antiparallel. Another way of detecting the <scene name='Sheets_in_Proteins/Syn_sheet7/1'>antiparallel sheet</scene> is by displaying as cartoon. The adjacent chains align so that <scene name='Sheets_in_Proteins/Syn_sheet4/1'>hydrogne bonds</scene> are formed between the imino hydrogens of one chain and the carbonyl oxygens of an adjacent chain. Psi and phi values that permit this alignment in antiparallel sheets have <scene name='Sheets_in_Proteins/Syn_sheet5/1'>mean values</scene> of 135<sup>0</sup> and -139<sup>0</sup>, respectively. The mean values for a parallel sheet are . | A β-pleated sheet contains multiple peptide strands that are positioned adjacent to one another (such as the one <scene name='Sheets_in_Proteins/Syn sheet1/2'>shown</scene> on the right). The planes of the <scene name='Sheets_in_Proteins/Syn_sheet2/2'>pleats</scene> are formed by the planes of the peptide bond. The alpha carbons of the peptide chain are at the valleys and peaks of the pleats. The peptides are <scene name='Sheets_in_Proteins/Syn_sheet3/3'>rainbow colored</scene> (blue amino end changing to red carboxy end) to show that the adjacent peptides are running in opposite directions making the sheet antiparallel. Another way of detecting the <scene name='Sheets_in_Proteins/Syn_sheet7/1'>antiparallel sheet</scene> is by displaying as cartoon. The adjacent chains align so that <scene name='Sheets_in_Proteins/Syn_sheet4/1'>hydrogne bonds</scene> are formed between the imino hydrogens of one chain and the carbonyl oxygens of an adjacent chain. Psi and phi values that permit this alignment in antiparallel sheets have <scene name='Sheets_in_Proteins/Syn_sheet5/1'>mean values</scene> of 135<sup>0</sup> and -139<sup>0</sup>, respectively. The mean values for a parallel sheet are . | ||
| - | Twisted | + | Twisted sheets are found in globular proteins. Unlike the <scene name='Sheets_in_Proteins/Syn_sheet6/1'>above two types</scene> of sheets the valleys and the peaks of a <scene name='Sheets_in_Proteins/Gly_phosyl2/1'>twisted sheet</scene><ref>Sheet present in domain 2 of [[1abb]].</ref> do not fall on parallel lines. Observe that the sheet is <scene name='Sheets_in_Proteins/Gly_phosyl/4'>parallel</scene>, and showing <scene name='Sheets_in_Proteins/Gly_phosyl3/1'>hydrogen bonds</scene>. |
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| + | == Notes and References == | ||
| + | <references/> | ||
Revision as of 18:26, 16 February 2011
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A β-pleated sheet contains multiple peptide strands that are positioned adjacent to one another (such as the one on the right). The planes of the are formed by the planes of the peptide bond. The alpha carbons of the peptide chain are at the valleys and peaks of the pleats. The peptides are (blue amino end changing to red carboxy end) to show that the adjacent peptides are running in opposite directions making the sheet antiparallel. Another way of detecting the is by displaying as cartoon. The adjacent chains align so that are formed between the imino hydrogens of one chain and the carbonyl oxygens of an adjacent chain. Psi and phi values that permit this alignment in antiparallel sheets have of 1350 and -1390, respectively. The mean values for a parallel sheet are .
Twisted sheets are found in globular proteins. Unlike the of sheets the valleys and the peaks of a [1] do not fall on parallel lines. Observe that the sheet is , and showing .
Notes and References
Proteopedia Page Contributors and Editors (what is this?)
Karl Oberholser, Karsten Theis, Jaime Prilusky, Eric Martz, Angel Herraez
