“…Concurrently, other methods for structural determination, such as X-ray crystallography, nuclear magnetic resonance (NMR), and infrared broad spectrum, along with biochemical assays, also provide a robust and complementary boost to the characterization and understanding of macromolecular dynamics and interactions [12,13]. Si-Bo Chen et al 2023 [12] revealed that a novel bacterial dipeptidyl peptidase III (CoDPP III) exists in a dimeric and closed conformation in the absence of a ligand and accumulates peptides and amino acids to serve as an A-signal, as evidenced by biochemical characterization and crystallization.…”