Figure 1

Schematic representation of the domain structure of the OSM fusion variants. The eight OSM fusion variants were designed using the Gateway cloning method. His6, hexa(poly)histidine; Trx, thioredoxin; Sumo, small ubiquitin-related modifier; GST, glutathione-S-transferase; PDIb‘a’, b‘a’ domain of full-length human PDI; MBP, maltose-binding protein; Nusa, N-utilisation substance protein A; PDI, full-length human PDI. His6 tag was fused to the N-terminus of Trx, GST, MBP and Nusa; His8 tag was fused to the N-terminus of Sumo, PDIb′a′ and PDI. Fusion protein expression is driven by the IPTG-inducible T7 promoter, with ampicillin as the selection marker. The arrow indicates the TEV protease cleavage site.