1.20.1.1 by small-scale protein purification 691424 1.20.1.1 Ni Sepharose column chromatography 744126 1.20.1.1 Ni2+-affinity column chromatography and Superdex 200 gel filtration 746256 1.20.1.1 on Ni2+ affinity resin 690884 1.20.1.1 recombinant and native protein 287854 1.20.1.1 recombinant enzymes using His-tag 657956, 658120 1.20.1.1 recombinant protein 287853, 726694