HypA, a nickel accessory protein from H. pylori, binds a zinc ion in it's structural site, a loop with two conserved CXXC motifs (Ac-ELECKDCSHVFKPNALDYGVCEKCHS-NH(2)). There are at least three hypotheses on the binding mode of this ion. In this paper, we try to understand how Zn(2+) binds to this fragment and why Ni(2+), a metal with quite a high affinity towards thiolic sites, doesn't compete with zinc in the binding to this motif. Potentiometric titrations, mass spectrometry, NMR, UV-Vis and CD spectroscopy help us to compare the coordination modes in both metal complexes and discuss their thermodynamic stabilities.
Rowinska Zyrek, M., Potocki, S., Witkowska, D., Valensin, D., Kozlowski, H. (2013). The zinc-binding fragment of HypA from Helicobacter pylori: a tempting site also for nickel ions. DALTON TRANSACTIONS, 42(17), 6012-6020 [10.1039/c2dt32195e].
The zinc-binding fragment of HypA from Helicobacter pylori: a tempting site also for nickel ions
VALENSIN, DANIELA;
2013-01-01
Abstract
HypA, a nickel accessory protein from H. pylori, binds a zinc ion in it's structural site, a loop with two conserved CXXC motifs (Ac-ELECKDCSHVFKPNALDYGVCEKCHS-NH(2)). There are at least three hypotheses on the binding mode of this ion. In this paper, we try to understand how Zn(2+) binds to this fragment and why Ni(2+), a metal with quite a high affinity towards thiolic sites, doesn't compete with zinc in the binding to this motif. Potentiometric titrations, mass spectrometry, NMR, UV-Vis and CD spectroscopy help us to compare the coordination modes in both metal complexes and discuss their thermodynamic stabilities.
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https://hdl.handle.net/11365/973781