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E. coli trp repressor forms a domain-swapped array in aqueous alcohol.

Catherine L Lawson·Brian Benoff·Tatyana Berger·Helen M Berman·Jannette Carey
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Abstract

The E. coli trp repressor (trpR) homodimer recognizes its palindromic DNA binding site through a pair of flexible helix-turn-helix (HTH) motifs displayed on an intertwined helical core. Flexible N-terminal arms mediate association between dimers bound to tandem DNA sites. The 2.5 A X-ray structure of trpR crystallized in 30% (v/v) isopropanol reveals a substantial conformational rearrangement of HTH motifs and N-terminal arms, with the protein appearing in the unusual form of an ordered 3D domain-swapped supramolecular array. Small angle X-ray scattering measurements show that the self-association properties of trpR in solution are fundamentally altered by isopropanol.

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2-PropanolAlcoholsAmino Acid MotifsAmino Acid SequenceAnimalsBacterial ProteinsBinding SitesCrystallography, X-RayDimerizationEscherichia coliModels, MolecularMolecular Sequence DataProtein ConformationProtein Structure, SecondaryProtein Structure, TertiaryRepressor ProteinsScattering, RadiationX-RaysEscherichia coli ProteinsJournal ArticleResearch Support, U.S. Gov't, Non-P.H.S.Research Support, U.S. Gov't, P.H.S.

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Catherine L Lawson, Brian Benoff, Tatyana Berger, Helen M Berman, Jannette Carey. 2004. E. coli trp repressor forms a domain-swapped array in aqueous alcohol.. https://doi.org/10.1016/j.str.2004.03.019

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