Molecular mechanisms of copper resistance and accumulation in bacteria

FEMS Microbiol Rev. 1994 Aug;14(4):381-6. doi: 10.1111/j.1574-6976.1994.tb00112.x.


An unusual mechanism of metal resistance is found in certain plant pathogenic strains of Pseudomonas syringae that are exposed to high levels of copper compounds used in disease control on agricultural crops. These bacteria accumulate blue Cu2+ ions in the periplasm and outer membrane. At least part of this copper sequestering activity is determined by copper-binding protein products of the copper resistance operon (cop). Potential copper-binding sites of the periplasmic CopA protein show conservation with type-1, type-2, and type-3 copper sites of several eukaryotic multi-copper oxidases. In addition to compartmentalization of copper in the periplasm, two components of the cop operon, copC and copD, appear to function in copper uptake into the cytoplasm. Copper resistance operons related to cop have been described in the related plant pathogen Xanthomonas campestris and in Escherichia coli, but these resistance systems may differ functionally from the Pseudomonas syringae system.

Publication types

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

MeSH terms

  • Amino Acid Sequence
  • Bacteria / drug effects
  • Bacteria / genetics
  • Bacteria / metabolism*
  • Bacterial Proteins / genetics
  • Chromosomes, Bacterial
  • Copper / pharmacokinetics*
  • Copper / pharmacology
  • Drug Resistance, Microbial
  • Molecular Sequence Data
  • Operon


  • Bacterial Proteins
  • CopA protein, Bacteria
  • Copper