1.1.1.81 recombinant His-tag protein from Escherichia coli 1.1.1.81 recombinant His-tagged enzyme from Escherichia coli strain Rose-gami B (DE3) by nickel affinity chromatography and desalting gel filtration 1.1.1.81 recombinant His-tagged wild-type and mutant enzymes from Escherichia coli by nickel affinity chromatography, the His-tag is cleaved by thrombin followed by gel filtration, over 95% purity 1.1.1.81 recombinant protein from Escherichia coli 1.1.1.81 recombinant tagged enzyme HPR2 from hpr1-knockout mutant Arabidopsis thaliana strain by ammonium sulfate fractionation, ion-exchange and affinity chromatography 1.1.1.81 Resource Q column chromatography and Superose 12 column chromatography