Western blot detection of recombinant SUMO-1 protein using Sheep antibody to SUMO-1 (6-21): ws, (catalogue no. S-064-100) at a dilution of 1:8000. The protein sample was 1 µl of E.Coli cell lysate containing approximately 50 ng of recombinant SUMO-1 protein. This antibody recognises a major band of approximately 17 kDa corresponding to SUMO-1, as well as a smaller minor band of 8 kDa.