Protein G and Related Products
Protein G is an immunoglobulin-binding protein expressed in group C and G Streptococcal bacteria much like Protein A but with differing specificities. It is a 65-kDa (G148 protein G) and a 58 kDa (C40 protein G) cell surface protein that has found application in purifying antibodies through its binding to the Fab and Fc region. The native molecule also binds albumin, however, because serum albumin is a major contaminant of antibody sources, the albumin binding site has been removed from recombinant forms of Protein G. BioVision is very excited to introduce Protein G related products. We have pure Protein G, Protein G Antibodies, Protein G coated plates, Protein G-Agarose, Protein G-Biotin, Protein G-Sepharose and Protein G Magnetic beads. These genetically engineered proteins contain only the IgG binding regions and have 6X His-tag on their N-terminus. Other non-specific domains have been eliminated to ensure the maximum specific IgG binding. The 6X His-tag on their N-terminus can be used for affinity purification or for protein A/G detection using anti-His-tag antibody (Cat. # 3998-100). These unique, high quality recombinant Proteins are produced in E. coli, and purified using multiple chromatographic steps (not affinity purified with human IgG). Purity is > 98% by SDS-PAGE and HPLC. Endotoxin level is < 0.05 EU/mg of Protein. These proteins bind to most mammalian immunoglobulins in their Fc binding domains and therefore are ideal for purification of polyclonal or monoclonal IgG antibodies.