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2b22
From Proteopedia
(New page: 200px<br /><applet load="2b22" size="450" color="white" frame="true" align="right" spinBox="true" caption="2b22, resolution 2.00Å" /> '''Antiparallel four-st...) |
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| - | [[Image:2b22.gif|left|200px]]<br /><applet load="2b22" size=" | + | [[Image:2b22.gif|left|200px]]<br /><applet load="2b22" size="350" color="white" frame="true" align="right" spinBox="true" |
caption="2b22, resolution 2.00Å" /> | caption="2b22, resolution 2.00Å" /> | ||
'''Antiparallel four-stranded coiled coil specified by a 3-3-1 hydrophobic heptad repeat'''<br /> | '''Antiparallel four-stranded coiled coil specified by a 3-3-1 hydrophobic heptad repeat'''<br /> | ||
==Overview== | ==Overview== | ||
| - | Coiled-coil sequences in proteins commonly share a seven-amino acid repeat | + | Coiled-coil sequences in proteins commonly share a seven-amino acid repeat with nonpolar side chains at the first (a) and fourth (d) positions. We investigate here the role of a 3-3-1 hydrophobic repeat containing nonpolar amino acids at the a, d, and g positions in determining the structures of coiled coils using mutants of the GCN4 leucine zipper dimerization domain. When three charged residues at the g positions in the parental sequence are replaced by nonpolar alanine or valine side chains, stable four-helix structures result. The X-ray crystal structures of the tetramers reveal antiparallel, four-stranded coiled coils in which the a, d, and g side chains interlock in a combination of knobs-into-knobs and knobs-into-holes packing. Interfacial interactions in a coiled coil can therefore be prescribed by hydrophobic-polar patterns beyond the canonical 3-4 heptad repeat. The results suggest that the conserved, charged residues at the g positions in the GCN4 leucine zipper can impart a negative design element to disfavor thermodynamically more stable, antiparallel tetramers. |
==About this Structure== | ==About this Structure== | ||
| - | 2B22 is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Saccharomyces_cerevisiae Saccharomyces cerevisiae] with NA as [http://en.wikipedia.org/wiki/ligand ligand]. Full crystallographic information is available from [http:// | + | 2B22 is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Saccharomyces_cerevisiae Saccharomyces cerevisiae] with <scene name='pdbligand=NA:'>NA</scene> as [http://en.wikipedia.org/wiki/ligand ligand]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=2B22 OCA]. |
==Reference== | ==Reference== | ||
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[[Category: Deng, Y.]] | [[Category: Deng, Y.]] | ||
[[Category: Eliezer, D.]] | [[Category: Eliezer, D.]] | ||
| - | [[Category: Kallenbach, N | + | [[Category: Kallenbach, N R.]] |
[[Category: Liu, J.]] | [[Category: Liu, J.]] | ||
[[Category: Lu, M.]] | [[Category: Lu, M.]] | ||
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[[Category: protein structure]] | [[Category: protein structure]] | ||
| - | ''Page seeded by [http:// | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 16:33:21 2008'' |
Revision as of 14:33, 21 February 2008
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Antiparallel four-stranded coiled coil specified by a 3-3-1 hydrophobic heptad repeat
Overview
Coiled-coil sequences in proteins commonly share a seven-amino acid repeat with nonpolar side chains at the first (a) and fourth (d) positions. We investigate here the role of a 3-3-1 hydrophobic repeat containing nonpolar amino acids at the a, d, and g positions in determining the structures of coiled coils using mutants of the GCN4 leucine zipper dimerization domain. When three charged residues at the g positions in the parental sequence are replaced by nonpolar alanine or valine side chains, stable four-helix structures result. The X-ray crystal structures of the tetramers reveal antiparallel, four-stranded coiled coils in which the a, d, and g side chains interlock in a combination of knobs-into-knobs and knobs-into-holes packing. Interfacial interactions in a coiled coil can therefore be prescribed by hydrophobic-polar patterns beyond the canonical 3-4 heptad repeat. The results suggest that the conserved, charged residues at the g positions in the GCN4 leucine zipper can impart a negative design element to disfavor thermodynamically more stable, antiparallel tetramers.
About this Structure
2B22 is a Single protein structure of sequence from Saccharomyces cerevisiae with as ligand. Full crystallographic information is available from OCA.
Reference
Antiparallel four-stranded coiled coil specified by a 3-3-1 hydrophobic heptad repeat., Deng Y, Liu J, Zheng Q, Eliezer D, Kallenbach NR, Lu M, Structure. 2006 Feb;14(2):247-55. PMID:16472744
Page seeded by OCA on Thu Feb 21 16:33:21 2008
