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2b22
From Proteopedia
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[[Image:2b22.gif|left|200px]] | [[Image:2b22.gif|left|200px]] | ||
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'''Antiparallel four-stranded coiled coil specified by a 3-3-1 hydrophobic heptad repeat''' | '''Antiparallel four-stranded coiled coil specified by a 3-3-1 hydrophobic heptad repeat''' | ||
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[[Category: Lu, M.]] | [[Category: Lu, M.]] | ||
[[Category: Zheng, Q.]] | [[Category: Zheng, Q.]] | ||
| - | [[Category: | + | [[Category: Ala coil]] |
| - | [[Category: | + | [[Category: Antiparallel tetramer]] |
| - | [[Category: | + | [[Category: Coiled coil]] |
| - | [[Category: | + | [[Category: Protein design]] |
| - | [[Category: | + | [[Category: Protein structure]] |
| - | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Sat May 3 19:45:21 2008'' | |
| - | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on | + | |
Revision as of 16:45, 3 May 2008
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. 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 Sat May 3 19:45:21 2008
