In addition to the cryo-EM structure of OR51E2 and propionate, the authors of deposited a 500 ns molecular dynamics (MD) trajectory at 310 K to the GPCRmd repository (Record 1245) . The simulation did not include the associated G protein, but was placed in a simulated lipid bilayer surrounded by water. We sampled twenty-six coordinate snapshots at 20 ns intervals from the trajectory, including the starting structure, to simulate thermal fluctuations in the system, and computed infrared spectra via quantum mechanics/molecular mechanics (QM/MM) in the harmonic approximation.