Protein A (Recombinant)
Recombinant protein A binds immunoglobulins (primarily IgG) at the Fc region with high affinity. In some cases, IgM and IgA will also bind. This property provides a rapid, simple and economical method for purification and analysis of a broad-spectrum of antibodies. Fractionation of IgG subclasses can also be performed using recombinant protein A. Because of its high affinity for immunoglobulins of many species and its low level of non-specific binding, recombinant protein A is useful for the study of cell surface antigens and receptors, and for detecting antibody-secreting cells. Recombinant protein A is produced in an E. coli strain which contains the gene for mature protein A from Staphylococcus aureus Cowan I strain.