2RML

Solution structure of the N-terminal soluble domains of Bacillus subtilis CopA

Summary for 2RML

• Entry DOI: 10.2210/pdb2rml/pdb
• Related: 1OQ3
• NMR Information: BMRB: 11011
• Descriptor: Copper-transporting P-type ATPase copA (1 entity in total)
• Functional Keywords: copa, p-type atpase, atp-binding, copper, copper transport, hydrolase, ion transport, magnesium, membrane, metal-binding, nucleotide-binding, phosphorylation, transmembrane, transport
• Biological source: Bacillus subtilis
• Cellular location: Cell membrane; Multi-pass membrane protein: O32220
• Total number of polymer chains: 1
• Total formula weight: 15932.17

Authors

Singleton, C.,Banci, L.,Bertini, I.,Ciofi-Baffoni, S.,Tenori, L.,Kihlken, M.A.,Boetzel, R.,Le Brun, N.E. (deposition date: 2007-10-30, release date: 2008-02-26, Last modification date: 2024-05-29)

Primary citation

Singleton, C.,Banci, L.,Ciofi-Baffoni, S.,Tenori, L.,Kihlken, M.A.,Boetzel, R.,Le Brun, N.E.
Structure and Cu(I)-binding properties of the N-terminal soluble domains of Bacillus subtilis CopA
Biochem.J., 411:571-579, 2008

PubMed Abstract: CopA, a P-type ATPase from Bacillus subtilis, plays a major role in the resistance of the cell to copper by effecting the export of the metal across the cytoplasmic membrane. The N-terminus of the protein features two soluble domains (a and b), that each contain a Cu(I)-binding motif, MTCAAC. We have generated a stable form of the wild-type two-domain protein, CopAab, and determined its solution structure. This was found to be similar to that reported previously for a higher stability S46V variant, with minor differences mostly confined to the Ser(46)-containing beta3-strand of domain a. Chemical-shift analysis demonstrated that the two Cu(I)-binding motifs, located at different ends of the protein molecule, are both able to participate in Cu(I) binding and that Cu(I) is in rapid exchange between protein molecules. Surprisingly, UV-visible and fluorescence spectroscopy indicate very different modes of Cu(I) binding below and above a level of 1 Cu(I) per protein, consistent with a major structural change occurring above 1 Cu(I) per CopAab. Analytical equilibrium centrifugation and gel filtration results show that this is a result of Cu(I)-mediated dimerization of the protein. The resulting species is highly luminescent, indicating the presence of a solvent-shielded Cu(I) cluster.

PubMed: 18215122
DOI: 10.1042/BJ20071620

Experimental method

SOLUTION NMR