4.1.3.16 - 2159, 5237, 5238, 5243, 5252, 5253, 5255 4.1.3.16 kidney enzyme 5255 4.1.3.16 Ni-NTA column chromatography 746867 4.1.3.16 phenyl Sepharose column chromatography, Sepharose Q column chromatography, and Superdex 200 gel filtration 746641