2.5.1.144	ammonium sulfate precipitation, DE52 column chromatography, hydroxyapatite column chromatography, and Sephadex G 100 gel filtration	
2.5.1.144	ammonium sulfate precipitation, DEAE-cellulose DE-32 column chromatography, DEAE-Sepharose CL-6B column chromatography, DEAE-cellulose DE-53 column chromatography, hydroxylapatite column chromatography, and Sephacryl S-200 gel filtration	
2.5.1.144	Ni-NTA column chromatography	
2.5.1.144	recombinant His-tagged enzyme from Escherichia coli by nickel affinity chromatography