Structure of the ATP binding domain from the Archaeoglobus fulgidus Cu+-ATPase.
The P-type ATPases translocate cations across membranes using the energy provided by ATP hydrolysis. CopA from Archaeoglobus fulgidus is a hyperthermophilic ATPase responsible for the cellular export of Cu+ and is a member of the heavy metal P1B-type ATPase subfamily, which includes the related Wilson and Menkes diseases proteins. The Cu+-ATPases are distinct from their P-type counter-parts in ion binding sequences, membrane topology, and the presence of cytoplasmic metal binding domains, suggesting that they employ alternate forms of regulation and novel mechanisms of ion transport. To gain insight into Cu+-ATPase function, the structure of the CopA ATP binding domain (ATPBD) was determined to 2.3 A resolution. Similar to other P-type ATPases, the ATPBD includes nucleotide binding (N-domain) and phosphorylation (P-domain) domains. The ATPBD adopts a closed conformation similar to the nucleotide-bound forms of the Ca2+-ATPase. The CopA ATPBD is much smaller and more compact, however, revealing the minimal elements required for ATP binding, hydrolysis, and enzyme phosphorylation. Structural comparisons to the AMP-PMP-bound form of the Escherichia coli K+-transporting Kdp-ATPase and to the Wilson disease protein N-domain indicate that the five conserved N-domain residues found in P1B-type ATPases, but not in the other families, most likely participate in ATP binding. By contrast, the P-domain includes several residues conserved among all P-type ATPases. Finally, the CopA ATPBD structure provides a basis for understanding the likely structural and functional effects of various mutations that lead to Wilson and Menkes diseases.
Department of Biochemistry, Molecular Biology, and Cell Biology, Northwestern University, Evanston, Illinois 60208, USA.
Matthew H
MH
Sazinsky
Atin K
AK
Mandal
José M
JM
Argüello
Amy C
AC
Rosenzweig
D000251:Adenosine Triphosphatases / Q000737:chemistry* / Q000378:metabolism; D000255:Adenosine Triphosphate / Q000737:chemistry*; D000595:Amino Acid Sequence; D019611:Archaeoglobus fulgidus / Q000201:enzymology*; D001692:Biological Transport; D002118:Calcium / Q000378:metabolism; D027682:Cation Transport Proteins / Q000737:chemistry; D003001:Cloning, Molecular; D003300:Copper / Q000737:chemistry / Q000378:metabolism; D003593:Cytoplasm / Q000378:metabolism; D004926:Escherichia coli / Q000378:metabolism; D006527:Hepatolenticular Degeneration / Q000378:metabolism; D006801:Humans; D006868:Hydrolysis; D007706:Menkes Kinky Hair Syndrome / Q000378:metabolism; D008958:Models, Molecular; D008969:Molecular Sequence Data; D011188:Potassium / Q000737:chemistry; D011485:Protein Binding; D011487:Protein Conformation; D017433:Protein Structure, Secondary; D017434:Protein Structure, Tertiary; D017386:Sequence Homology, Amino Acid
D027682:Cation Transport Proteins; D003300:Copper; D000255:Adenosine Triphosphate; D000251:Adenosine Triphosphatases; D011188:Potassium; D002118:Calcium