Interaction of the CopZ copper chaperone with the CopA copper ATPase of Enterococcus hirae assessed by surface plasmon resonance

Biochem Biophys Res Commun. 2001 Oct 19;288(1):172-7. doi: 10.1006/bbrc.2001.5757.

Abstract

Intracellular copper routing in Enterococcus hirae can be accomplished by the CopZ metallochaperone. Using surface plasmon resonance analysis, we show here that CopZ interacts with the CopA copper ATPase. The binding affinity of CopZ for CopA was increased in the presence of copper, due to a 15-fold lower dissociation rate constant. Mutating the N-terminal copper binding motif of CopA from CxxC to SxxS abolished this copper-induced effect. Moreover, CopZ failed to show an interaction with an unrelated copper binding protein used as a control. These results show that (i) the CopA copper ATPase specifically interacts with the CopZ chaperone, (ii) this interaction is based on protein-protein interaction, and (iii) surface plasmon resonance is a novel tool for quantitative analysis of metallochaperone-target interactions.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adenosine Triphosphatases / metabolism
  • Bacterial Proteins / metabolism*
  • Copper / pharmacology
  • Enterococcus / enzymology
  • Enterococcus / metabolism*
  • Kinetics
  • Molecular Chaperones / metabolism
  • Surface Plasmon Resonance
  • Trans-Activators / metabolism*

Substances

  • Bacterial Proteins
  • CopA protein, Bacteria
  • CopZ protein, Enterococcus hirae
  • Molecular Chaperones
  • Trans-Activators
  • Copper
  • Adenosine Triphosphatases