Copper(I) Coordination by Two Plant Metallothioneins

The plant metallothioneins (MTs) show high sequence diversity. Proposed to function mainly in metal ion homeostasis and detoxification these small cysteine‐rich proteins exhibit pronounced affinities to metal ions with the electron configuration d10. Having previously studied the coordination abilities of two MTs from Cicerarietinum (chickpea) for divalent metal ions we now aim to expand the knowledge to the binding characteristics for CuI. Performing titration studies followed by UV and circular dichroism spectroscopy distinct differences between the two proteins are revealed.