Crystal structure of the homo-tetrameric DNA binding domain of Escherichia coli single-stranded DNA-binding protein determined by multiwavelength x-ray diffraction on the selenomethionyl protein at 2.9-A resolution

Proc Natl Acad Sci U S A. 1997 Jun 24;94(13):6652-7. doi: 10.1073/pnas.94.13.6652.

Abstract

The crystal structure of the tetrameric DNA-binding domain of the single-stranded DNA binding protein from Escherichia coli was determined at a resolution of 2.9 A using multiwavelength anomalous dispersion. Each monomer in the tetramer is topologically similar to an oligomer-binding fold. Two monomers each contribute three beta-strands to a single six-stranded beta-sheet to form a dimer. Two dimer-dimer interfaces are observed within the crystal. One of these stabilizes the tetramer in solution. The other interface promotes a superhelical structure within the crystal that may reflect tetramer-tetramer interactions involved in the positive cooperative binding of the single-stranded DNA-binding protein to single-stranded DNA.

Publication types

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

MeSH terms

  • Amino Acid Sequence
  • Binding Sites
  • Crystallography, X-Ray
  • DNA, Single-Stranded / metabolism
  • DNA-Binding Proteins / chemistry*
  • DNA-Binding Proteins / metabolism
  • Escherichia coli / chemistry*
  • Models, Molecular
  • Molecular Sequence Data
  • Protein Conformation

Substances

  • DNA, Single-Stranded
  • DNA-Binding Proteins

Associated data

  • PDB/1KAW