Protein A

Protein A is a cell wall protein deriving from Staphylococcus aureus which exhibits unique binding properties for IgG from a variety of mammalian species and for some IgM and IgA as well. It binds with the Fc region of immunoglobulins through interaction with the heavy chain. It couples to a wide variety of reporter molecules including fluorescent dyes, enzyme markers, biotin, colloidal gold and radioactive iodine without affecting the antibody binding site. Recombinant Protein A was developed to increase the specificity of the molecule for IgG and is widely used both in research and bioprocessing. The recombinant protein A is produced by expressing a modified protein A gene in E.coli. A specific purification process with strict quality control was taken to get the recombinant protein A with the purity of more than 98% , no human IgG affinity step is used during validated fermentation and purification and devoid of bacterial contaminant found normally in native Protein A. (Free of Staphylococcus endotoxins and hemolysin).