Avidity for Polypeptide Binding by Nucleotide-Bound Hsp104 Structures

Biochemistry. 2017 Apr 18;56(15):2071-2075. doi: 10.1021/acs.biochem.7b00225. Epub 2017 Apr 10.

Abstract

Recent Hsp104 structural studies have reported both planar and helical models of the hexameric structure. The conformation of Hsp104 monomers within the hexamer is affected by nucleotide ligation. After nucleotide-driven hexamer formation, Hsp104-catalyzed disruption of protein aggregates requires binding to the peptide substrate. Here, we examine the oligomeric state of Hsp104 and its peptide binding competency in the absence of nucleotide and in the presence of ADP, ATPγS, AMPPNP, or AMPPCP. Surprisingly, we found that only ATPγS facilitates avid peptide binding by Hsp104. We propose that the modulation between high- and low-peptide affinity states observed with these ATP analogues is an important component of the disaggregation mechanism of Hsp104.

Publication types

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

MeSH terms

  • Adenosine Triphosphate / analogs & derivatives
  • Adenosine Triphosphate / metabolism
  • Heat-Shock Proteins / metabolism*
  • Peptides / metabolism*
  • Protein Binding
  • Saccharomyces cerevisiae Proteins / metabolism*

Substances

  • Heat-Shock Proteins
  • Peptides
  • Saccharomyces cerevisiae Proteins
  • adenosine 5'-O-(3-thiotriphosphate)
  • Adenosine Triphosphate