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

Protein Expr Purif. 2010 Sep;73(1):74-7. doi: 10.1016/j.pep.2010.03.014. 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.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Amino Acid Substitution
  • Animals
  • Biotin / genetics
  • Chromatography, Affinity / methods*
  • Cloning, Molecular
  • Electrophoresis, Polyacrylamide Gel
  • Escherichia coli / genetics
  • Glutathione Transferase / chemistry
  • Glutathione Transferase / genetics
  • Glutathione Transferase / metabolism*
  • Histidine / chemistry
  • Histidine / genetics
  • Histidine / metabolism*
  • Humans
  • Models, Molecular
  • Molecular Sequence Data
  • Nickel / metabolism*
  • Recombinant Fusion Proteins / chemistry
  • Recombinant Fusion Proteins / genetics
  • Recombinant Fusion Proteins / metabolism*
  • Schistosoma japonicum / enzymology*
  • Schistosoma japonicum / genetics
  • Sequence Alignment
  • Structure-Activity Relationship

Substances

  • Recombinant Fusion Proteins
  • Histidine
  • Biotin
  • Nickel
  • Glutathione Transferase