Role of metal-binding domains of the copper pump from Archaeoglobus fulgidus.

CopA from the extreme thermophile Archaeoglobus fulgidus is a P-type ATPase that transports Cu(+) and Ag(+) and has individual metal-binding domains (MBDs) at both N- and C-termini. We expressed and purified full-length CopA as well as constructs with MBDs deleted either individually or collectively. Cu(+) and Ag(+)-dependent ATPase assays showed that full-length CopA had submicromolar affinity for both ions, but was inhibited by concentrations above 1muM.