Protein L is a bacterial surface protein isolated from Peptostreptoccocus magnus, and recombinant protein L is produced in E.coli. Unlike Protein A and Protein G, which bind primarily through Fc regions of immunoglobilins, Protein L binds Igs through interactions with the light kappa chain of all classes of immunoglobulin such as IgG, IgM, IgA, IgE, IgD, and Fab fragments. It also binds to single-chain antibody fragments (scFv).
PurKine™ Protein L Resin 4FF has been designed to purify mammalian IgG that contain specific kappa light chains from serum, ascites fluid, cell culture supernantant and other antibody samples.The Resin consists of 90μm beads of cross-linked 4% agarose, to which Recombinant protein L has been coupled. More than 15mg human lgG can be captured by per mL of this resin. No decrease in performance occurs after at least five repeated uses. In addition, its high flow properties make it excellent for scaling-up.
In a word, PurKine™ Protein L Resin 4FF is a versatile affinity resin which can be apply in purifying monoclonal and polyclonal antibodies which bind poorly to Protein A or Protein G, monoclonal antibodies from culture supernatants supplemented with bovine serum ( it does not bind bovine immunoglobilins), immunoprecipitation and co-immunoprecipitation assays, ScFv and Fab fragments containing kappa light chains.