Examining the Effect of an Anion-Binding Reagent on the Structure of Deprotonated Leucine Enkephalin Using Cryogenic-Ion Infrared Action Spectroscopy.

Biomolecular systems feature a complex interaction network comprising numerous intra- and intermolecular interactions. By isolating biomolecules under vacuum conditions, the intricate balance between specific interaction motifs can be characterized with precise control over conditions. In this study, we apply cryogenic-ion infrared action spectroscopy and electronic structure methods to examine the structural changes in the deprotonated form of the model peptide leucine enkephalin (YGGFL) upon complexation with diserinol isophthalamide (DIP), an anion-binding reagent.