Anti-ySUMO Antibody - Western Blot. Western blot of ySUMO fusion protein. Anti-ySUMO antibody, generated by immunization with recombinant yeast SUMO, was tested by western blot against a SUMO-GFP fusion protein (lane 2). While the actual molecular weight of the fusion protein is 39 kD, the protein migrates as a 49 kD band (arrowhead). No reactivity is seen for lane 1 which contains His-tagged GFP protein. The membrane was blocked using BLOTTO. Primary antibody was used at a 1:1000 dilution in BLOTTO. The membrane was washed and reacted with a 1:10000 dilution of IRDye 800 Conjugated Affinity Purified Goat-anti-Mouset IgG (H&L) MX10 (800 nm channel). Molecular weight estimation was made by comparison to prestained MW markers indicated at the right (lane M, 700 nm channel). Other detection systems will yield similar results.