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Hydrophobic side-chain size is a determinant of the three-dimensional structure of the p53 oligomerization domain.

ABSTRACT: The p53 tumor suppressor oligomerization domain, a dimer of two primary dimers, is an independently folding domain whose subunits consist of a beta-strand, a tight turn and an alpha-helix. To evaluate the effect of hydrophobic side-chains on three-dimensional structure, we substituted residues Phe341 and Leu344 in the alpha-helix with other hydrophobic amino acids. Substitutions that resulted in residue 341 having a smaller side-chain than residue 344 switched the stoichiometry of the domain from tetrameric to dimeric. The three-dimensional structure of one such dimer was determined by multidimensional NMR spectroscopy. When compared with the primary dimer of the wild-type p53 oligomerization domain, the mutant dimer showed a switch in alpha-helical packing from anti-parallel to parallel and rotation of the alpha-helices relative to the beta-strands. Hydrophobic side-chain size is therefore an important determinant of a protein fold.

SUBMITTER: McCoy M

PROVIDER: S-EPMC1326307 | biostudies-other | 1997 Oct

REPOSITORIES: biostudies-other

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Hydrophobic side-chain size is a determinant of the three-dimensional structure of the p53 oligomerization domain.

McCoy M M Stavridi E S ES Waterman J L JL Wieczorek A M AM Opella S J SJ Halazonetis T D TD

The EMBO journal 19971001 20

The p53 tumor suppressor oligomerization domain, a dimer of two primary dimers, is an independently folding domain whose subunits consist of a beta-strand, a tight turn and an alpha-helix. To evaluate the effect of hydrophobic side-chains on three-dimensional structure, we substituted residues Phe341 and Leu344 in the alpha-helix with other hydrophobic amino acids. Substitutions that resulted in residue 341 having a smaller side-chain than residue 344 switched the stoichiometry of the domain fro ...[more]

PMID: 9321402

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Dataset Information

Hydrophobic side-chain size is a determinant of the three-dimensional structure of the p53 oligomerization domain.

Publications

Hydrophobic side-chain size is a determinant of the three-dimensional structure of the p53 oligomerization domain.

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