MEAP purification by Ni Sepharose 6 Fast Flow. Lane 1: Supernatant. Lane 2: Flow-through. Lane 3: Elution. Lane 4: Sumo-MEAP digested by sumo protease. Lane 5: Purified MEAP. Lane M: Protein marker. Note: Red, blue and black arrow indicate the purified the sumo-MEAP, the MEAP and the sumo tag, respectively.