High-resolution structure of an α-spectrin SH3-domain mutant with a redesigned hydrophobic core

Departamento de Química-Física, Bioquímica y Química Inorgánica, Universidad de Almería, Carretera Sacramento, Almería 04120, Spain.
Acta Crystallographica Section F Structural Biology and Crystallization Communications (Impact Factor: 0.53). 09/2010; 66(Pt 9):1023-7. DOI: 10.1107/S1744309110030095
Source: PubMed


The alpha-spectrin SH3 domain (Spc-SH3) is a small modular domain which has been broadly used as a model protein in folding studies and these studies have sometimes been supported by structural information obtained from the coordinates of Spc-SH3 mutants. The structure of B5/D48G, a multiple mutant designed to improve the hydrophobic core and as a consequence the protein stability, has been solved at 1 A resolution. The crystals belonged to the orthorhombic space group P2(1)2(1)2(1), with unit-cell parameters a=24.79, b=37.23, c=62.95 A. This mutant also bears a D48G substitution in the distal loop and this mutation has also been reported to increase the stability of the protein by itself. The structure of the B5/D48G mutant shows a highly packed hydrophobic core and a more ordered distal loop compared with previous Spc-SH3 structures.

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