Show simple item record

dc.contributor.authorXiao, Z
dc.contributor.authorBrose, J
dc.contributor.authorSchimo, S
dc.contributor.authorAckland, SM
dc.contributor.authorLa Fontaine, S
dc.contributor.authorWedd, AG
dc.identifierpii: S0021-9258(20)53726-5
dc.identifier.citationXiao, Z., Brose, J., Schimo, S., Ackland, S. M., La Fontaine, S. & Wedd, A. G. (2011). Unification of the Copper(I) Binding Affinities of the Metallo-chaperones Atx1, Atox1, and Related Proteins DETECTION PROBES AND AFFINITY STANDARDS. JOURNAL OF BIOLOGICAL CHEMISTRY, 286 (13), pp.11047-11055.
dc.descriptionC1 - Journal Articles Refereed
dc.description.abstractLiterature estimates of metal-protein affinities are widely scattered for many systems, as highlighted by the class of metallo-chaperone proteins, which includes human Atox1. The discrepancies may be attributed to unreliable detection probes and/or inconsistent affinity standards. In this study, application of the four Cu(I) ligand probes bicinchoninate, bathocuproine disulfonate, dithiothreitol (Dtt), and glutathione (GSH) is reviewed, and their Cu(I) affinities are re-estimated and unified. Excess bicinchoninate or bathocuproine disulfonate reacts with Cu(I) to yield distinct 1:2 chromatophoric complexes [Cu(I)L(2)](3-) with formation constants β(2) = 10(17.2) and 10(19.8) m(-2), respectively. These constants do not depend on proton concentration for pH ≥7.0. Consequently, they are a pair of complementary and stable probes capable of detecting free Cu(+) concentrations from 10(-12) to 10(-19) m. Dtt binds Cu(I) with K(D) ∼10(-15) m at pH 7, but it is air-sensitive, and its Cu(I) affinity varies with pH. The Cu(I) binding properties of Atox1 and related proteins (including the fifth and sixth domains at the N terminus of the Wilson protein ATP7B) were assessed with these probes. The results demonstrate the following: (i) their use permits the stoichiometry of high affinity Cu(I) binding and the individual quantitative affinities (K(D) values) to be determined reliably via noncompetitive and competitive reactions, respectively; (ii) the scattered literature values are unified by using reliable probes on a unified scale; and (iii) Atox1-type proteins bind Cu(I) with sub-femtomolar affinities, consistent with tight control of labile Cu(+) concentrations in living cells.
dc.subjectBioinorganic Chemistry; Expanding Knowledge in the Chemical Sciences
dc.titleUnification of the Copper(I) Binding Affinities of the Metallo-chaperones Atx1, Atox1, and Related Proteins DETECTION PROBES AND AFFINITY STANDARDS
dc.typeJournal Article
melbourne.peerreviewPeer Reviewed
melbourne.affiliationThe University of Melbourne
melbourne.source.titleJournal of Biological Chemistry
melbourne.contributor.authorXiao, Zhiguang
melbourne.contributor.authorBROSE, JENS
melbourne.contributor.authorWedd, Anthony
melbourne.accessrightsAccess this item via the Open Access location

Files in this item


There are no files associated with this item.

This item appears in the following Collection(s)

Show simple item record