Fig. 3
From: Simplified cloning and isolation of peptides from “sandwiched” SUMO-peptide-intein fusion proteins
Isolation and purification of LeuA as a SPI fusion protein. (A) SDS-PAGE results over the course of LeuA purification. MW = molecular weight in kilodaltons; 1 = molecular weight protein ladder; 2 = pooled fractions of first Ni-NTA column; 3 = after overnight incubation in 100 mM βME; 4 = after dialysis; 5 = second Ni-NTA column flow through; 6 = second Ni-NTA column 5 mM imidazole wash; 7 = second Ni-NTA column 500 mM imidazole wash; 8 = molecular weight protein ladder. (B) MALDI-TOF MS after intein cleavage. (C) MALDI-TOF MS of pure LeuA after HPLC. The inlaid purple box shows an expansion of the LeuA mass peak