A Novel Metal Adsorbent Composed of a Hexa-histidine Tag and a Carbohydrate-binding Module on Cellulose

Abstract We developed a novel metal adsorbent composed of bio-based materials, cellulose and a protein. The approach involved the immobilization of a hexa-histidine tag ($ His_{6} $), which shows an affinity for an intermediate acid (metal ion) in Hard and Soft Acids and Bases (HSAB) theory, on cell...
Ausführliche Beschreibung

Abstract We developed a novel metal adsorbent composed of bio-based materials, cellulose and a protein. The approach involved the immobilization of a hexa-histidine tag ($ His_{6} $), which shows an affinity for an intermediate acid (metal ion) in Hard and Soft Acids and Bases (HSAB) theory, on cellulose by fusing with a carbohydrate-binding module (CBM). The results show that CBM-His6-bound cellulose has adsorption selectivity reflecting the original properties of $ His_{6} $. Additionally, we prepared three configurations of CBM-$ His_{6} $ proteins, which were subsequently immobilized on filter paper for $ Ni^{2+} $ ion adsorption. Of these configurations, we found that the protein containing two $ His_{6} $ tags at each terminus (N- and C-) of CBM exhibited the highest metal adsorption ability. Furthermore, XPS analysis confirmed the binding of $ Ni^{2+} $ ions on the cellulose. Ausführliche Beschreibung