1.17.1.8 | cells grown in M9 medium containing 2H, 15N, and 13C-labeled sources, collected, lysed, and protein purified with a QA52 anion exchange column and a Blue Trisacryl affinity column with gravity gradient chromatography, fractions with activity pooled and concentrated using an Amicon ultrafiltration device with YM10 membrane, desalted and loaded onto the Blue Trisacryl affinity column and eluted with a linear gradient of 0-2 M NaCl, 25 mM Tris buffer, pH 7.5, pooled, concentrated and buffer ecxchanged |