Structure of the cro repressor from bacteriophage lambda and its interaction with DNA

Nature. 1981 Apr 30;290(5809):754-8. doi: 10.1038/290754a0.


The three-dimensional structure of the 66-amino acid cro repressor protein of bacteriophage lambda suggests how it binds to its operator DNA. We propose that a dimer of cro protein is bound to the B-form of DNA with the 2-fold axis of the dimer coincident with the 2-fold axis of DNA. A pair of 2-fold-related alpha-helices of the repressor, lying within successive major grooves of the DNA, seem to be a major determinant in recognition and binding. In addition, the C-terminal residues of the protein, some of which are disordered in the absence of DNA, appear to contribute to the binding.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Bacteriophage lambda
  • Carrier Proteins*
  • DNA*
  • DNA, Viral / metabolism*
  • DNA-Binding Proteins
  • Macromolecular Substances
  • Nucleic Acid Conformation
  • Protein Binding
  • Protein Conformation
  • Repressor Proteins*
  • Structure-Activity Relationship
  • Transcription Factors*
  • Viral Proteins
  • X-Ray Diffraction


  • Carrier Proteins
  • DNA, Viral
  • DNA-Binding Proteins
  • Macromolecular Substances
  • Repressor Proteins
  • Transcription Factors
  • Viral Proteins
  • DNA