Anion-Facilitated Hydrogen-Deuterium Exchange as a Tool to Probe Weak Anion-Protein Interactions Responsible for Hofmeister Effects.

ABSTRACT: Impeded by the complexity of proteinaceous structure and the very weak nature of the noncovalent interactions involved, the detailed mechanisms by which anions induce salting-in Hofmeister effects in proteins and peptides remain unclear. Here, using β-hairpin peptides as models, we examine two approaches to qualify (map) anion binding: ¹H NMR chemical shifts and hydronium-catalyzed hydrogen-deuterium exchange (HDX) rate changes. We demonstrate that each salt investigated─despite an affinity too weak to quantify accurately, caused denaturation to an extent that is both peptide and anion-specific, with more charge-diffuse anions inducing a greater degree of unfolding. Our studies reveal that the HDX mapping provides more detail than chemical shift data. Thus, HDX mapping reveals t

SUBMITTER: Tran TH 

PROVIDER: S-EPMC11873968 | biostudies-literature | 2025 Feb

REPOSITORIES: biostudies-literature