Strong Uranium(VI) Binding onto Bovine Milk Proteins, Selected Protein Sequences, and Model Peptides

Research output: Contribution to journalResearch articleContributedpeer-review

Contributors

  • Harald Zaenker - , Helmholtz-Zentrum Dresden-Rossendorf (HZDR) (Author)
  • Katja Heine - , Berliner Glas (Author)
  • Stephan Weiss - , Helmholtz-Zentrum Dresden-Rossendorf (HZDR) (Author)
  • Vinzenz Brendler - , Helmholtz-Zentrum Dresden-Rossendorf (HZDR) (Author)
  • Richard Husar - , Helmholtz-Zentrum Dresden-Rossendorf (HZDR) (Author)
  • Gert Bernhard - , Helmholtz-Zentrum Dresden-Rossendorf (HZDR) (Author)
  • Karsten Gloe - , TUD Dresden University of Technology (Author)
  • Thomas Henle - , Chair of Food Chemistry, TUD Dresden University of Technology (Author)
  • Astrid Barkleit - , Helmholtz-Zentrum Dresden-Rossendorf (HZDR) (Author)

Abstract

Hexavalent uranium is ubiquitous in the environment. In view of the chemical and radiochemical toxicity of uranium(VI), a good knowledge of its possible interactions in the environment is crucial. The aim of this work was to identify typical binding and sorption characteristics of uranium(VI) with both the pure bovine milk protein beta-casein and diverse related protein mixtures (caseins, whey proteins). For comparison, selected model peptides representing the amino acid sequence 13-16 of beta-casein and dephosphorylated beta-casein were also studied. Complexation studies using potentiometric titration and time-resolved laser-induced fluorescence spectroscopy revealed that the phosphoryl-containing proteins form uranium(VI) complexes of higher stability than the structure-analog phosphoryl-free proteins. That is in agreement with the sorption experiments showing a significantly higher affinity of caseins toward uranium(VI) in comparison to whey proteins. On the other hand, the total sorption capacity of caseins is lower than that of whey proteins. The discussed binding behavior of milk proteins to uranium(VI) might open up interesting perspectives for sustainable techniques of uranium(VI) removal from aqueous solutions. This was further demonstrated by batch experiments on the removal of uranium(VI) from mineral water samples.

Details

Original languageEnglish
Pages (from-to)4173-4189
Number of pages17
JournalInorganic chemistry
Volume58
Issue number7
Publication statusPublished - 1 Apr 2019
Peer-reviewedYes

External IDs

Scopus 85063097465

Keywords

Keywords

  • HIGHLY PHOSPHORYLATED PROTEIN, GLUTAMYL RESIDUES, URANYL BINDING, DRINKING-WATER, IONS BINDING, METAL-IONS, CASEIN, COMPLEXES, RECOVERY, ACTINIDE