Peptide-Level Interactions between Proteins and Small-Molecule Drug Candidates by Two Hydrogen-Deuterium Exchange MS-Based Methods: The Example of Apolipoprotein E3.

ABSTRACT: We describe a platform utilizing two methods based on hydrogen-deuterium exchange (HDX) coupled with mass spectrometry (MS) to characterize interactions between a protein and a small-molecule ligand. The model system is apolipoprotein E3 (apoE3) and a small-molecule drug candidate. We extended PLIMSTEX (protein-ligand interactions by mass spectrometry, titration, and H/D exchange) to the regional level by incorporating enzymatic digestion to acquire binding information for peptides. In a single experiment, we not only identified putative binding sites, but also obtained affinities of 6.0, 6.8, and 10.6 μM for the three different regions, giving an overall binding affinity of 7.4 μM. These values agree well with literature values determined by accepted methods. Unlike those methods, PLIMSTE

SUBMITTER: Wang H 

PROVIDER: S-EPMC5655995 | biostudies-literature | 2017 Oct

REPOSITORIES: biostudies-literature