PMID: 20347989

Authors:

Han YH, Seo HA, Kim GH, Lee CK, Kang YK, Ryu KH, Chung YJ

Title:

A histidine substitution confers metal binding affinity to a Schistosoma japonicum Glutathione S-transferase.

Journal:

Protein Expr Purif. 2010 Sep;73(1):74-7. Epub 2010 Mar 27.

Abstract:

Glutathione S-transferases (GSTs) are multifunctional enzymes that are used as fusion tags on recombinant proteins in mammalian and Escherichia coli expression systems. We recently found that the Schistosoma japonicum GST (SjGST) displays weak Ni(2+) ion binding affinity. Glu26 and His79 were assumed to be its Ni(2+) binding sites based on the structure of the 26-kDa Clonorchis sinensis GST. To enhance SjGST Ni(2+) binding affinity, Glu26 was mutated to His. SjGST-E26H was expressed and purified at a high concentration of imidazole to a higher purity than wild type SjGST. In addition, human biotin protein ligase fused to SjGST-E26H was purified with a immobilized Ni affinity column.