Off-campus UMass Amherst users: To download dissertations, please use the following link to log into our proxy server with your UMass Amherst user name and password.

Non-UMass Amherst users, please click the view more button below to purchase a copy of this dissertation from Proquest.

(Some titles may also be available free of charge in our Open Access Dissertation Collection, so please check there first.)

Mass spectrometry methods for studying protein-metal binding

Jia Dong, University of Massachusetts Amherst


This dissertation focuses on the mass spectrometric based methods for studying protein-metal binding. Identifying metal-protein interaction is a key step in understanding metal-binding protein structure and function. A phenomenon associated with gas phase dissociation behavior of metal-peptide complexes has been investigated. A positive correlation was found between the number of strong coordination groups in the peptide sequence and the degree of c and z ion formation after electron transfer dissociation of the peptide-metal complexes. Establishing thermochemical cycle enables a theoretical understanding of the process. A new mass spectrometric method has been developed to identify Zn-bound His residues in Zn-metalloproteins relies on variations in the hydrogen deuterium exchange of the C2 hydrogen of His side chains. We show that this approach can be used to study the Zn-bound His residue in human &beta-2-microglobulin; (&beta2m;), a monomeric protein that has been shown to aggregate into amyloid fibrils in dialysis patients leading to dialysis-related amyloidosis. The different effect of three divalent transition metals including Cu(II), Ni(II) and Zn(II) on &beta2m; oligomerization and fibril formation under physiological conditions is described. We found that Cu(II) can induced &beta2m; oligomerization and amyloidosis. In contrast, no oligomeric species can be formed with Ni(II), and only oligomers can be formed with Zn(II). A combination of metal catalyzed oxidation (MCO)-MS, hydrogen deuterium exchange (HDX)-MS and other spectroscopic techniques is utilized to obtain insights into the mechanism of Cu(II)-induced &beta2m; amyloidosis. We elucidate the different ways that these metals bind &beta2m;, thereby identifying key features of the &beta2m-Cu;(II) interaction that are essential for enabling this protein to form amyloid fibrils.^

Subject Area

Chemistry|Analytical chemistry

Recommended Citation

Dong, Jia, "Mass spectrometry methods for studying protein-metal binding" (2014). Doctoral Dissertations Available from Proquest. AAI3615409.