Abstract
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 1 μM. Deletion of both MBDs had no effect on affinity but resulted in loss of this inhibition. Individual deletions implicated the N-terminal MBD in causing the inhibition at concentrations >1 μM. Rates of phosphoenzyme decay indicated that neither the dephosphorylation step, nor the E1P–E2P equilibrium accounted for this inhibition, suggesting the involvement of a different catalytic step. Alternative hypotheses are discussed by which the N-terminal MBD could influence the catalytic activity of CopA.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callMore From: Biochemical and Biophysical Research Communications
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
