Protein-DNA conformational changes in the crystal structure of a lambda Cro-operator complex.

Journal Article (Journal Article)

The structure of a complex of bacteriophage lambda Cro protein with a 17-base-pair operator has been determined at 3.9-A resolution. Isomorphous derivatives obtained by the synthesis of site-specific iodinated DNA oligomers were of critical importance in solving the structure. The crystal structure contains three independent Cro-operator complexes that have very similar, although not necessarily identical, conformations. In the complex, the protein dimer undergoes a large conformational change relative to the crystal structure of the free protein. One monomer rotates by about 40 degrees relative to the other, this being accomplished primarily by a twisting of the two beta-sheet strands that connect one monomer with the other. In the complex, the DNA is bent by about 40 degrees into the shape of a boomerang but maintains essentially Watson-Crick B-form. In contrast to other known protein-DNA complexes, the DNA is not stacked end-to-end. The structure confirms the general features of the model previously proposed for the interaction of Cro with DNA.

Full Text

Duke Authors

Cited Authors

  • Brennan, RG; Roderick, SL; Takeda, Y; Matthews, BW

Published Date

  • October 1990

Published In

Volume / Issue

  • 87 / 20

Start / End Page

  • 8165 - 8169

PubMed ID

  • 2146682

Pubmed Central ID

  • PMC54913

International Standard Serial Number (ISSN)

  • 0027-8424

Digital Object Identifier (DOI)

  • 10.1073/pnas.87.20.8165


  • eng

Conference Location

  • United States