Relative Interchain Disulfide Bond Labilities in Human F(ab') 2μ Fragments 1

Summary

IgM was prepared from the plasma of a patient suffering with Waldenström's macroglobulinemia. The protein was fragmented with trypsin and F(ab')_2μ was isolated from the digestion mixture. The fragments readily dissociated into Fab' after treatment with 0.004 M mercaptoethylamine. The μ-light chain disulfide bonds were not broken. In F(ab')_2μ fragments, the inter-μ, chain disulfide bond is more susceptible to reduction with mercaptoethylamine than μ-light chain bonds.