Physics Commons^™

Structure And Metal Binding Properties Of Znua, A Periplasmic Zinc Transporter From Escherichia Coli, Liliya A. Yatsunyk, J. Allen Easton, Lydia R. Kim, Stacy A. Sugarbaker, Brian Bennett, Robert M. Breece, Ivan I. Vorontsov, David L. Tierney, Michael W. Crowder, Amy C. Rosenzweig

Physics Faculty Research and Publications

ZnuA is the periplasmic Zn²⁺-binding protein associated with the high-affinity ATP-binding cassette ZnuABC transporter from Escherichia coli. Although several structures of ZnuA and its homologs have been determined, details regarding metal ion stoichiometry, affinity, and specificity as well as the mechanism of metal uptake and transfer remain unclear. The crystal structures of E. coli ZnuA (Eco-ZnuA) in the apo, Zn²⁺-bound, and Co²⁺-bound forms have been determined. ZnZnuA binds at least two metal ions. The first, observed previously in other structures, is coordinated tetrahedrally by Glu59, His60, His143, and His207. Replacement of Zn^{2+ …}