PDZ-like domains mediate binding specificity in the Clp/Hsp100 family of chaperones and protease regulatory subunits

Cell. 1997 Dec 26;91(7):939-47. doi: 10.1016/s0092-8674(00)80485-7.


ClpX, a molecular chaperone and the regulatory subunit of the ClpXP protease, is shown to contain tandem modular domains that bind to the C-terminal sequences of target proteins in a manner that parallels functional specificity. Nuclear magnetic resonance studies show that these C-terminal sequences are displayed as disordered peptides on the surface of otherwise folded proteins. The ClpX substrate-binding domains are homologous to sequences in other Clp/Hsp100 proteins and are related more distantly to PDZ domains, which also mediate C-terminal specific protein-protein interactions. Conservation of these binding domains indicates that the mode of substrate recognition characterized here for ClpX will be a conserved feature among Clp/Hsp100 family members and a distinguishing characteristic between this chaperone family and the Hsp70 chaperones.

Publication types

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

MeSH terms

  • ATPases Associated with Diverse Cellular Activities
  • Adenosine Triphosphatases / metabolism*
  • Amino Acid Sequence
  • Binding Sites
  • Endopeptidase Clp
  • Escherichia coli
  • Escherichia coli Proteins
  • Heat-Shock Proteins / metabolism*
  • Magnetic Resonance Spectroscopy
  • Molecular Chaperones / metabolism*
  • Molecular Sequence Data
  • Protein Binding
  • Protein Conformation
  • Protein Folding
  • Protozoan Proteins / metabolism*
  • Serine Endopeptidases / metabolism*


  • Escherichia coli Proteins
  • Heat-Shock Proteins
  • Molecular Chaperones
  • Protozoan Proteins
  • Serine Endopeptidases
  • Endopeptidase Clp
  • Adenosine Triphosphatases
  • ClpB protein, Leishmania
  • ClpX protein, E coli
  • ATPases Associated with Diverse Cellular Activities

Associated data

  • PDB/P03815
  • PDB/P15716
  • PDB/P23865
  • PDB/P31007
  • PDB/P31016
  • PDB/P31539