2.9.1.1 - 22913 2.9.1.1 ammonium sulfate precipitation, hydroxyapatite column chromatography, Hi Trap Q column chromatography, and Superdex 200 gel filtration 739586 2.9.1.1 centrifugation at 150000 xg, followed by succesive chromatography of the supernatant on DEAE-cellulose, Sephacryl S-300 and Heparin-Toyopearl 661290 2.9.1.1 recombinant C-terminally His6-tagged SecS from Escherichia coli strain Rosetta2(DE3) by nickel affinity chromatography and gel filtration to over 95% purity 693212 2.9.1.1 recombinant SelA from Escherichia coli strain DH5alpha by anion exchange chromatography, ammonium sulfate fractionation, and gel filtration 691146