Interaction of cysteine with Cu²⁺ and group IIb (Zn²⁺, Cd²⁺, Hg²⁺) metal cations: a theoretical study

Abstract

The structure and energetics of complexes obtained upon interaction between cysteine and Zn2+, Cd2+, Hg2+ and Cu2+ cations were studied using quantum chemical density functional theory calculations with the 6-311++G** orbital basis set and relativistic pseudopotentials for the cations. Different coordination sites for metal ions on several cysteine conformers were considered. In their lowest energy complexes with the amino acid, the Zn2+ and Cd2+ cations appear to be three-coordinated to carbonyl oxygen, nitrogen and sulfur atoms, whereas the Cu2+ and Hg2+ ions are coordinated to both the carbonyl oxygen and sulfur atoms of one of the zwitterion forms of the amino acid. Bonds of metal cations with the coordination sites are mainly ionic except those established with sulfur, which show a small covalent character that become most significant when Cu2+ and Hg2+ are involved. The order of metal ion affinity proposed is Cu>Zn>Hg>Cd.

Characterization of a novel marine microbial esterase and its use to make D-methyl lactate

“…PHE14 was also quite stable in the presence of multiple organic solvents, surfactants and metal ions, thus making it a very good esterase candidate for organic synthesis that requires an organic solvent, surfactant or metal ion. Similar behavior was observed with other microbial esterases [18][19][20][21]. PHE14 was also characterized to be a salt-tolerant microbial esterase.…”

Structural characterization of gas-phase cysteine and cysteine methyl ester complexes with zinc and cadmium dications by infrared multiple photon dissociation spectroscopy

“…These structures are similar to the GSs found in previous work for H + (Cys), 39 M + (Cys) where M = Li and Na, 20 as well as predictions by Russo et al of M 2+ (Cys) where M = Cu, Zn, Cd and Hg. 8 Previous theoretical work in the Armentrout group has found that the CS structures The IRMPD action spectra shown correspond to the fractional yield of the product ions as a function of free electron laser wavenumber.…”

Probing the coordination properties of glutathione with transition metal ions (Cr2+,Mn2+,Fe2+,Co2+, Ni2+,Cu2+,Zn2+,Cd2+,Hg2+) by density functional theory

“…Nevertheless, it is difficult to explain the structures of the complexes at the atomic and electronic level. Computational studies can fill this gap and provide thermochemical, kinetic and structural information [33]. Furthermore, the different affinities of a specific ligand for different metal cations, which play a key role in the function and properties of metal-containing biomolecules, can also be obtained directly by quantum-chemical computations [34,35].…”