Protein L from Peptostreptococcus magnus binds immunoglobulins (Ig) primarily through kappa light chain interactions without interfering with the antigen binding sites of Ig′s. This means that Protein L binds to a wider range of Ig classes and subclasses from a variety of species than any other commercially available Ig binding protein. It contains four Ig binding domains (B-domains). It may be used for the purification of IgG, IgM, IgA, IgE and IgD containing κ light chains and for the purification of Fab and scFv fragments containing κ light chains. It may be conjugated to a solid support for affinity purification or conjugated to marker molecules for use in detection. Protein L does not bind to bovine, sheep or goat immunoglobulins. For this reason it may be used for the purification of monoclonal antibodies from media supplemented with bovine serum albumin or fetal calf serum. It can also be used to purify human or mouse antibodies from goat, bovine or sheep proteins. A comprehensive list of binding properties is found in the product data sheet.
