Halophilic Metal Binding Protein and Its His-Asp Repeating Peptides as Fusion Partners for High Solubility and Affinity-Purification of Fusion Proteins

Abstract

Histidine-rich metal binding protein（HP）has been found to have high binding capacity to several heavy metal ions and was expressed in Escherichia coli cytoplasm as soluble form in large amount. Here, we employed properties of this halophilic HP as a solubility-enhancing partner protein for soluble expression and for immobilized metal ion affinity purification. We also demonstrated that a novel insertion sequence（HD50）of HP containing His-Asp repeating sequence exhibited metal binding capacity.