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1p7i
From Proteopedia
CRYSTAL STRUCTURE OF ENGRAILED HOMEODOMAIN MUTANT K52A
Overview
We report the crystal structures and biophysical characterization of two stabilized mutants of the Drosophila Engrailed homeodomain that have been engineered to minimize electrostatic repulsion. Four independent copies of each mutant occupy the crystal lattice, and comparison of these structures illustrates variation that can be partly ascribed to networks of correlated conformational adjustments. Central to one network is leucine 26 (Leu26), which occupies alternatively two side chain rotameric conformations (-gauche and trans) and different positions within the hydrophobic core. Similar sets of conformational substates are observed in other Engrailed structures and in another homeodomain. The pattern of structural adjustments can account for NMR relaxation data and sequence co-variation networks in the wider homeodomain family. It may also explain the dysfunction associated with a P26L mutation in the human ARX homeodomain protein. Finally, we observe a novel dipolar interaction between a conserved tryptophan and a water molecule positioned along the normal to the indole ring. This interaction may explain the distinctive fluorescent properties of the homeodomain family.
About this Structure
1P7I is a Single protein structure of sequence from Drosophila melanogaster. Full crystallographic information is available from OCA.
Reference
Crystal structures of engrailed homeodomain mutants: implications for stability and dynamics., Stollar EJ, Mayor U, Lovell SC, Federici L, Freund SM, Fersht AR, Luisi BF, J Biol Chem. 2003 Oct 31;278(44):43699-708. Epub 2003 Aug 15. PMID:12923178 Page seeded by OCA on Sat May 3 04:46:56 2008
