Protein L is a multi-domain protein found on the surface of Peptostreptococcus magnus, also known as Peptostreptococcus magnusProtein L (PPL). Unlike Protein A or Protein G, Protein L primarily binds to the kappa light chains of antibodies without interfering with the antigen-binding site. This unique binding mechanism enables Protein L to interact with a broader range of antibody classes and subtypes, including human IgG, IgM, IgA, and IgD containing kappa light chains, as well as mouse IgG and IgM, rat IgG, Fab fragments, single-chain variable fragments (ScFv), and more. The recombinant Protein L is engineered by expressing five antibody-binding domains derived from the native protein, retaining the complete antibody-binding functionality of natural Protein L.Molecular Weight: 41.5 kDa