Recombinant Protein A

Description:
Recombinant Protein A is an immunoglobulin-binding protein derived from the cell wall of the bacterium Staphylococcus aureus. It is composed of five homologous Ig-binding domains that fold into a three-helix bundle. Each domain is able to bind proteins from many of mammalian species, most notably IgGs. Protein A binds with high affinity to human IgG1 and IgG2 as well as mouse IgG2a and IgG2b. Protein A binds with moderate affinity to human IgM, IgA and IgE as well as to mouse IgG3 and IgG1. It does not react with human IgG3 or IgD, nor will it react to mouse IgM, IgA or IgE. It binds the heavy chain with the Fc region of most immunoglobulins and also within the Fab region in the case of the human VH3 family. Through these interactions in serum, where IgG molecules are bound in the wrong orientation (in relation to normal antibody function), the bacteria disrupts opsonization and phagocytosisties.

Applications:

• Antibody purification
• Protein purification
• Isolates immune complexes

Source:
Purified from E.coli that carries the protein A gene of Staphylococcus aureus.

Purity:
>98% by SDS-PAGE and HPLC analyses.

Recommended Storage Conditions:
-20ºC. Avoid freeze / thaw cycles.