Unknown

Dataset Information

0

Chaperone-mediated Cu+ delivery to Cu+ transport ATPases: requirement of nucleotide binding.


ABSTRACT: Cu(+)-ATPases drive the efflux of Cu(+) from the cell cytoplasm. During their catalytic/transport cycle, cytoplasmic Cu(+)-chaperones deliver the metal to the two transmembrane metal-binding sites (TM-MBSs) responsible for Cu(+) translocation. Here, using Archaeoglobus fulgidus Cu(+)-ATPase CopA and the C-terminal Cu(+)-chaperone domain of CopZ (Ct-CopZ), we describe the mechanism of Cu(+) transfer to both TM-MBSs. In absence of other ligands, Ct-CopZ transfers Cu(+) to wild-type CopA and to various CopA constructs lacking or having mutated cytoplasmic metal-binding domains, in a fashion consistent with occupancy of a single TM-MBS. Similar experiments performed in the presence of 2.5 mm ADP-Mg(2+), stabilizing an E1.ADP, lead to full occupancy of both TM-MBSs. In both cases, the transfer is largely stoichiometric, i.e. equimolar amounts of Ct-CopZ.Cu(+) saturated the TM-MBSs. Experiments performed with CopA mutants lacking either TM-MBS showed that both sites are loaded independently, and nucleotide binding does not affect their availability. The nucleotide-induced E2-->E1 transition is structurally characterized by a large displacement of the A and N domains opening the cytoplasmic region of P-type ATPases. Then, it is apparent that, whereas the first Cu(+)-chaperone can bind an ATPase form available in the absence of ligands, the second requires the E1.nucleotide intermediary to interact and deliver the metal. Interestingly, independent of TM-MBS Cu(+) loading, nucleotide binding also prevents the regulatory interaction of the N-terminal cytoplasmic metal-binding domain with the nucleotide binding domain.

SUBMITTER: Gonzalez-Guerrero M 

PROVIDER: S-EPMC2742845 | biostudies-literature | 2009 Jul

REPOSITORIES: biostudies-literature

altmetric image

Publications

Chaperone-mediated Cu+ delivery to Cu+ transport ATPases: requirement of nucleotide binding.

González-Guerrero Manuel M   Hong Deli D   Argüello José M JM  

The Journal of biological chemistry 20090612 31


Cu(+)-ATPases drive the efflux of Cu(+) from the cell cytoplasm. During their catalytic/transport cycle, cytoplasmic Cu(+)-chaperones deliver the metal to the two transmembrane metal-binding sites (TM-MBSs) responsible for Cu(+) translocation. Here, using Archaeoglobus fulgidus Cu(+)-ATPase CopA and the C-terminal Cu(+)-chaperone domain of CopZ (Ct-CopZ), we describe the mechanism of Cu(+) transfer to both TM-MBSs. In absence of other ligands, Ct-CopZ transfers Cu(+) to wild-type CopA and to var  ...[more]

Similar Datasets

| S-EPMC4467857 | biostudies-literature
| S-EPMC3537068 | biostudies-literature
| S-EPMC2573086 | biostudies-literature
| S-EPMC2329688 | biostudies-literature
| S-EPMC5924815 | biostudies-literature
| S-EPMC3092005 | biostudies-literature
| S-EPMC4064014 | biostudies-literature
| S-EPMC6484131 | biostudies-literature
| S-EPMC5025381 | biostudies-literature
| S-EPMC8233418 | biostudies-literature