, inhibitor-bound dengue virus NS2B/NS3 protease (two binding modes, 2m9p and 2m9q) , pro-islet amyloid polypeptide in detergent micelles (6ucj and 6uck) , E. coli tryptophan repressor (two states combined as pdb ID 5tm0) , and the membrane-bound SARS-CoV-2 spike protein HR1 ectodomain (two states combined as 7r95) . Also shown is the three-state model of influenza hemagglutinin fusion peptide A (combined as 2lwa) (C and D). Schematic representations for the data organization required for deposition of multiple-state models into the PDB and BMRB: (C) Fast or intermediate exchange between the conformers yields population-averaged chemical shifts, resulting in one or more sets of restraints and corresponding PDB coordinate sets. (D) Slow exchange between conformers leads to distinct chemical shifts, with multiple chemical shift entries from a single NMR dataset that are then used to calculate multiple sets of PDB coordinates. As in the fast/intermediate exchange case, a single set of chemical shifts arising from one slow-exchange ensemble may generate multiple restraints, leading to multiple coordinate sets, depending on the data analysis method. Multiple-state models may also be generated from a single restraint set in certain cases.