Metal Binding Ability of Small Peptides Containing Cysteine Residues

Abstract

The Cd(II)‐, Pb(II)‐, Ni(II)‐ and Zn(II)‐complexes of small terminally protected peptides containing CXXX, XXXC, XCCX, CX n C ( n =1–3) sequences have been studied with potentiometric, UV/Vis and CD spectroscopic techniques. The cysteine thiolate group is the primary binding site for all studied metal ions, but the presence of a histidyl or aspartyl side chain in the molecule contributes to the stability of the complexes. For two‐cysteine containing peptides the (S − ,S − ) coordinated species are formed in the physiological pH range and the stability increases in the Ni(II)<Zn(II)<Pb(II)<Cd(II) order. As a conclusion, the inserting of −CXXC− sequence into the peptide makes the synthesis of peptides with high selectivity to toxic Cd(II) or Pb(II) ion possible. In addition, the spectroscopic characterization of these complexes can contribute to the discovery of the exact binding site and binding mode of longer peptides mimicking the biologically important proteins.

Histidine Ligated Iron‐Sulfur Peptides

“…To investigate the ability of small peptides containing both Cys and His to coordinate metal ions similarly to proteins, fourteen different peptides and N‐acetyl Cys methyl ester (N−Ac‐Cys‐OMe) and N‐acetyl His methyl ester (N−Ac‐His‐OMe) were incubated with Fe 2+ , Co 2+ , and Zn 2+ and spectroscopically evaluated. Cys‐containing peptides, but not peptides that contained both Cys and His, were previously demonstrated to coordinate transition metals [16,17] . Here, we focused on the binding of Fe 2+ because iron ions were easily accessible before the great oxidation event, [18] are frequently found in model prebiotic pathways, [19–22] and are exploited throughout extant metabolism.…”

“…Cys-containing peptides, but not peptides that contained both Cys and His, were previously demonstrated to coordinate transition metals. [16,17] Here, we focused on the binding of Fe 2 + because iron ions were easily accessible before ChemBioChem the great oxidation event, [18] are frequently found in model prebiotic pathways, [19][20][21][22] and are exploited throughout extant metabolism. Zn 2 + was investigated because this metal ion can bind to the same motifs as iron-sulfur clusters, [2] and Zn 2 + has been hypothesized to be important in early evolution.…”

Physiological and Molecular Effects of Calcium and Salicylic Acid on Fusarium graminearum-Infected Wheat Seedlings

“…These peptides with low molecular weight are abundant in cysteine residues (Cys) and frequently have a characteristic pattern of sulfurcontaining amino acids. MTs were reported to be involved in ROS scavenging and metal homeostasis (Lukács et al 2021). In wheat seedlings inoculated with F. graminearum, the acquired data showed that the expression of the MT gene was significantly upregulated.…”

Upcycling of spent functional biocarbon adsorbents to catalysts for the conversion of C5/C6 carbohydrates into platform chemicals

“…Optimized structures of complex with hydroxy and amino groups had complexes with bifurcated coordination bonds from Ni 2+ ion to hydroxy and amino groups (Figure S8d and Figure S8f). The combination effect among functional groups can form bifurcated coordination structures, which would increase adsorption capacity, but not necessarily increase adsorption efficiency, because ligand formation with cysteine is a function of pH [39] and is favored with cysteine at high pH according to studies with small peptides [40].…”

“…The combination effect among functional groups can form bifurcated coordination structures, which would increase the adsorption capacity, but not necessarily increase the adsorption efficiency, because ligand formation with cysteine is a function of pH 39 and is favored with cysteine at high pH according to the studies with small peptides. 40 The effect of functional groups on the equilibrium amount of Ni 2+ adsorbed onto the biocarbon adsorbent (HC, B-HC, N-HC and BN-HC) was evaluated by varying the initial Ni 2+ ion solution concentration. Langmuir and Freundlich adsorption isothermal curves (Fig.…”