Understanding copper trafficking in bacteria: interaction between the copper transport protein CopZ and the N-terminal domain of the copper ATPase CopA from Bacillus subtilis.
In this paper the interaction of cytoplasmic CopZ and the N-terminal domain of the CopA ATPase from Bacillus subtilis has been studied by NMR through (15)N-(1)H HSQC experiments in order to understand the role of the two proteins in the whole copper trafficking mechanism of the bacteria. It appears that the two proteins interact in a fashion similar to that of the yeast homologue proteins [Arnesano, F., Banci, L., Bertini, I., Cantini, F., Ciofi-Baffoni, S., Huffman, D. L., and O'Halloran, T. V. (2001) J. Biol. Chem. 276, 41365-41376], although the surface potentials are reversed. A structural model for the interaction is proposed. (15)N mobility studies on the free proteins and on their complex are also reported. From these data, it appears that copper is largely transferred from CopZ to CopA, thus suggesting their possible involvement in a detoxification process. Comparing functional data of homologous proteins of other bacteria, it can be concluded that this class of proteins is involved in copper homeostasis but the specific roles are species dependent.
Banci
Lucia
L
Department of Chemistry, University of Florence, Via Luigi Sacconi 6, 50019 Sesto Fiorentino (Florence), Italy.
Bertini
Ivano
I
Ciofi-Baffoni
Simone
S
Del Conte
Rebecca
R
Gonnelli
Leonardo
L
D000251:Adenosine Triphosphatases / Q000737:chemistry / Q000378:metabolism*; D001059:Apoproteins / Q000737:chemistry; D001412:Bacillus subtilis / Q000201:enzymology / Q000378:metabolism*; D001426:Bacterial Proteins / Q000737:chemistry / Q000378:metabolism*; D001692:Biological Transport; D027682:Cation Transport Proteins / Q000737:chemistry / Q000378:metabolism*; D003300:Copper / Q000032:analysis / Q000378:metabolism*; D019281:Dimerization; D046911:Macromolecular Substances; D018832:Molecular Chaperones; D019906:Nuclear Magnetic Resonance, Biomolecular; D010446:Peptide Fragments / Q000737:chemistry / Q000378:metabolism*; D011485:Protein Binding; D017434:Protein Structure, Tertiary; D013816:Thermodynamics; D017186:Titrimetry; D015534:Trans-Activators / Q000737:chemistry / Q000378:metabolism*
D001059:Apoproteins; D001426:Bacterial Proteins; D027682:Cation Transport Proteins; C071263:CopA protein, Bacteria; C092379:CopZ protein, Enterococcus hirae; D046911:Macromolecular Substances; D018832:Molecular Chaperones; D010446:Peptide Fragments; D015534:Trans-Activators; C042514:cuprous ion; D003300:Copper; D000251:Adenosine Triphosphatases