The crystal structure of trp aporepressor at 1.8 A shows how binding tryptophan enhances DNA affinity

Nature. 1987 Jun;327(6123):591-7. doi: 10.1038/327591a0.

Abstract

Comparison of the crystal structure of inactive unliganded trp aporepressor with that of trp repressor shows that binding tryptophan activates the dimer a thousandfold by moving two symmetrically-disposed flexible bihelical motifs. These flexible 'DNA-reading heads' flank a highly inflexible core domain formed by an unusual arrangement of interlocking alpha-helices from both subunits.

Publication types

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

MeSH terms

  • Apoproteins / metabolism*
  • Bacterial Proteins*
  • Binding Sites
  • DNA / genetics*
  • DNA / metabolism
  • Escherichia coli Proteins*
  • Models, Molecular
  • Nucleic Acid Conformation
  • Protein Binding
  • Protein Conformation
  • Repressor Proteins / metabolism*
  • Transcription Factors / metabolism*
  • Tryptophan*

Substances

  • Apoproteins
  • Bacterial Proteins
  • Escherichia coli Proteins
  • Repressor Proteins
  • TRPR protein, E coli
  • Transcription Factors
  • Tryptophan
  • DNA