ABSTRACT

The structural heterogeneity exhibited by immunoglobulin light chains (LC) involved in amyloidosis has been a subject of interest in establishing a pathogenesis of the disease. Dimerization of the light chain is hypothesized to be the first step in the polymerization of the protein to amyloid fibrils. The use of reduction agents in the purification and/or sample preparation of light chain proteins for structural analysis may destroy relevant post-translational modifications. The mass spectrometry methods presented here enable high-sensitivity determination of post-translational modifications. Post-translational modifications, such as cysteinylation, of these amyloidogenic LCs may have been altered. The use of reduction agents in the purification and/or sample preparation of light chain proteins for structural analysis may destroy relevant post-translational modifications.