A tale of tails: deciphering the contribution of terminal tails to the biochemical properties of two Dps proteins from Streptomyces coelicolor

Cell Mol Life Sci. 2014 Dec;71(24):4911-26. doi: 10.1007/s00018-014-1658-4. Epub 2014 Jun 11.

Abstract

Dps proteins are members of an extensive family of proteins that oxidise and deposit iron in the form of ferric oxide, and are also able to bind DNA. Ferroxidation centres are formed at the interface of anti-parallel dimers, which further assemble into dodecameric nanocages with a hollow core where ferric oxide is deposited. Streptomyces coelicolor encodes three Dps-like proteins (DpsA, B and C). Despite sharing the conserved four-helix bundle organisation observed in members of the Dps family, they display significant differences in the length of terminal extensions, or tails. DpsA possess both N- and C-terminal tails of different lengths, and their removal affects quaternary structure assembly to varying degrees. DpsC quaternary structure, on the other hand, is heavily dependent on its N-terminal tail as its removal abolishes correct protein folding. Analysis of the crystal structure of dodecamers from both proteins revealed remarkable differences in the position of tails and interface surface area; and provides insight to explain the differences in biochemical behaviour observed while comparing DpsA and DpsC.

MeSH terms

  • Bacterial Proteins / chemistry*
  • Bacterial Proteins / genetics
  • Bacterial Proteins / metabolism
  • Crystallization
  • Crystallography, X-Ray
  • DNA-Binding Proteins / chemistry*
  • DNA-Binding Proteins / genetics
  • DNA-Binding Proteins / metabolism
  • Electrophoresis, Polyacrylamide Gel
  • Escherichia coli / genetics
  • Iron / chemistry
  • Iron / metabolism
  • Models, Molecular
  • Mutation
  • Protein Binding
  • Protein Isoforms / chemistry
  • Protein Isoforms / genetics
  • Protein Isoforms / metabolism
  • Protein Multimerization
  • Protein Structure, Quaternary
  • Protein Structure, Secondary
  • Protein Structure, Tertiary
  • Recombinant Proteins / chemistry*
  • Streptomyces coelicolor / genetics
  • Streptomyces coelicolor / metabolism*

Substances

  • Bacterial Proteins
  • DNA-Binding Proteins
  • DPS protein, Bacteria
  • Protein Isoforms
  • Recombinant Proteins
  • Iron