Analysis of the plasma metalloproteome by SEC-ICP-AES: bridging proteomics and metabolomics

Abstract

Although blood plasma inherently contains protein biomarkers for human disease diagnosis, their determination is difficult since more than 3700 proteins are commonly present. The associated protein-separation problem can, however, be dramatically simplified by analyzing plasma for a subproteome, such as those proteins that contain bound metals. To this end, the analysis of plasma by size-exclusion chromatography (SEC) coupled with an inductively coupled plasma atomic-emission spectrometer (ICP-AES), which served as the simultaneous Cu-, Fe- and Zn-specific detector, revealed the presence of approximately 12 metalloproteins within 25 min. In the context of modern proteomics research, SEC-ICP-AES therefore represents a viable proteomic approach that can be applied to diagnose human diseases that are associated with increased or decreased concentrations of certain plasma metalloproteins. Furthermore, SEC-ICP-AES can be employed to probe the effect of environmental chemicals or drugs in blood at the metalloprotein level, which makes it a versatile research tool for applications in toxicology, applied medicine, pharmacology and nutritional science.