Crystal structure of the met repressor-operator complex at 2.8 A resolution reveals DNA recognition by beta-strands

Nature. 1992 Oct 1;359(6394):387-93. doi: 10.1038/359387a0.


The crystal structure of the met repressor-operator complex shows two dimeric repressor molecules bound to adjacent sites 8 base pairs apart on an 18-base-pair DNA fragment. Sequence specificity is achieved by insertion of double-stranded antiparallel protein beta-ribbons into the major groove of B-form DNA, with direct hydrogen-bonding between amino-acid side chains and the base pairs. The repressor also recognizes sequence-dependent distortion or flexibility of the operator phosphate backbone, conferring specificity even for inaccessible base pairs.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Bacterial Proteins / chemistry*
  • Bacterial Proteins / metabolism*
  • Base Sequence
  • Crystallography*
  • DNA, Bacterial / chemistry
  • Escherichia coli / genetics
  • Escherichia coli Proteins*
  • Gene Expression Regulation, Bacterial / physiology*
  • Genes, Regulator*
  • Methionine / biosynthesis*
  • Molecular Conformation
  • Molecular Sequence Data
  • Operator Regions, Genetic / genetics*
  • Repressor Proteins / chemistry*
  • Repressor Proteins / metabolism*


  • Bacterial Proteins
  • DNA, Bacterial
  • Escherichia coli Proteins
  • Repressor Proteins
  • methionine repressor protein, Bacteria
  • methionine repressor protein, E coli
  • Methionine