1lli
From Proteopedia
| Line 1: | Line 1: | ||
[[Image:1lli.gif|left|200px]] | [[Image:1lli.gif|left|200px]] | ||
| - | + | <!-- | |
| - | + | The line below this paragraph, containing "STRUCTURE_1lli", creates the "Structure Box" on the page. | |
| - | + | You may change the PDB parameter (which sets the PDB file loaded into the applet) | |
| - | + | or the SCENE parameter (which sets the initial scene displayed when the page is loaded), | |
| - | | | + | or leave the SCENE parameter empty for the default display. |
| - | | | + | --> |
| - | + | {{STRUCTURE_1lli| PDB=1lli | SCENE= }} | |
| - | + | ||
| - | + | ||
| - | }} | + | |
'''THE CRYSTAL STRUCTURE OF A MUTANT PROTEIN WITH ALTERED BUT IMPROVED HYDROPHOBIC CORE PACKING''' | '''THE CRYSTAL STRUCTURE OF A MUTANT PROTEIN WITH ALTERED BUT IMPROVED HYDROPHOBIC CORE PACKING''' | ||
| Line 29: | Line 26: | ||
[[Category: Richards, F M.]] | [[Category: Richards, F M.]] | ||
[[Category: Sauer, R T.]] | [[Category: Sauer, R T.]] | ||
| - | [[Category: | + | [[Category: Double helix]] |
| - | [[Category: | + | [[Category: Protein-dna complex]] |
| - | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Sat May 3 00:02:18 2008'' | |
| - | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on | + | |
Revision as of 21:02, 2 May 2008
THE CRYSTAL STRUCTURE OF A MUTANT PROTEIN WITH ALTERED BUT IMPROVED HYDROPHOBIC CORE PACKING
Overview
The dense packing observed in protein interiors appears to be crucial for stabilizing the native structure--even subtle internal substitutions are usually destabilizing. Thus, steric complementarity of core residues is thought to be an important criterion for "inverse folding" predictive methods, which judge whether a newly determined sequence is consistent with any known folds. A major problem in the development of useful core packing evaluation algorithms, however, is that there are occasional mutations that are predicted to disrupt native packing but that yield an equally or more stable protein. We have solved the crystal structure of such a variant of lambda repressor, which, despite having three larger core substitutions, is more stable than the wild type. The structure reveals that the protein accommodates the potentially disruptive residues with shifts in its alpha-helical arrangement. The variant is apparently more stable because its packing is improved--the core has a higher packing density and little geometric strain. These rearrangements, however, cause repositioning of functional residues, which result in reduced DNA binding activity. By comparing these results with the predictions of two core packing algorithms, it is clear that the protein possesses a relatively high degree of main-chain flexibility that must be accounted for in order to predict the full spectrum of compatible core sequences. This study also shows how, in protein evolution, a particular set of core residue identities might be selected not because they provide optimal stability but because they provide sufficient stability in addition to the precise structure required for optimal activity.
About this Structure
1LLI is a Single protein structure of sequence from Enterobacteria phage lambda. Full crystallographic information is available from OCA.
Reference
The crystal structure of a mutant protein with altered but improved hydrophobic core packing., Lim WA, Hodel A, Sauer RT, Richards FM, Proc Natl Acad Sci U S A. 1994 Jan 4;91(1):423-7. PMID:8278404 Page seeded by OCA on Sat May 3 00:02:18 2008
