1D SDS-PAGE of ab88348 before and after treatment with glycosidases to remove oligosaccharides. Lane 1: ab88348 Lane 2: ab88348 treated with PNGase F to remove potential N-linked glycans Lane 3: ab88348 treated with a glycosidase cocktail to remove potential N- and O-linked glycans. The absence of a drop in MWt after treatment with PNGase F indicates that there are no N-linked glycans attached to the protein. A subsequent drop in MWt after treatment with the glycosidase cocktail indicates the presence of O-linked glycans. Additional bands in lane 2 and lane 3 are glycosidase enzymes.
A sample of ab88348 without carrier protein was reduced and alkylated and focused on a 3-10 IPG strip then run on a 4-20% Tris-HCl 2D gel. Approximately 40 µg of protein was load. Multiple spot trains indicate the presence of multiple isoforms of ab88348. Spots within both spot trains were cut from the gel and identified as ab88348 by protein mass fingerprinting.
Densitometry of protein isoforms visualised by 2-DE. The densitometry scan demonstrates the purified human cell expressed protein exists in multiple isoforms, which differ according to their level of post-translational modification. The triangle indicates the theoretical MWt and pI of the protein.