| Literature DB >> 15274929 |
Catherine L Lawson1, Brian Benoff, Tatyana Berger, Helen M Berman, Jannette Carey.
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.Entities:
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Year: 2004 PMID： 15274929 PMCID： PMC3228604 DOI： 10.1016/j.str.2004.03.019
Source DB: PubMed Journal: Structure ISSN： 0969-2126 Impact factor: 5.006