Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
1904451 | Biochimica et Biophysica Acta (BBA) - Molecular Basis of Disease | 2016 | 12 Pages |
•Study of common E3 of human α-ketoglutarate and pyruvate dehydrogenase complexes.•Effects of ten pathogenic mutations on human E3 structure examined by HDX-MS.•Structural changes identified account for loss in cofactor binding and activity.•Mutations lead to dysfunctional complexes and alter interactions in variants.•HDX-MS results suggest structural sources of elevated ROS-generating capacities.
Pathogenic amino acid substitutions of the common E3 component (hE3) of the human alpha-ketoglutarate dehydrogenase and the pyruvate dehydrogenase complexes lead to severe metabolic diseases (E3 deficiency), which usually manifest themselves in cardiological and/or neurological symptoms and often cause premature death. To date, 14 disease-causing amino acid substitutions of the hE3 component have been reported in the clinical literature. None of the pathogenic protein variants has lent itself to high-resolution structure elucidation by X-ray or NMR. Hence, the structural alterations of the hE3 protein caused by the disease-causing mutations and leading to dysfunction, including the enhanced generation of reactive oxygen species by selected disease-causing variants, could only be speculated. Here we report results of an examination of the effects on the protein structure of ten pathogenic mutations of hE3 using hydrogen/deuterium-exchange mass spectrometry (HDX-MS), a new and state-of-the-art approach of solution structure elucidation. On the basis of the results, putative structural and mechanistic conclusions were drawn regarding the molecular pathogenesis of each disease-causing hE3 mutation addressed in this study.
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