Abstract. In experiments at LLB and ILL we have measured low-resolution INS spectra and elastic scans for H2O- and D2O-hydrated samples of a 15-residue oligopeptide between 30 and 280 K. For a comprehensive interpretation of the peculiar changes in proton mobility observed between ~150 K and ~235 K, it would be highly informative to use OSIRIS or IRIS to obtain quasielastic data allowing detailed shape analyses along the lines of those for interfacial water on Vycor (Zanotti et al., 2005). The oligopeptide studied is an antibacterial drug prepared by means of step-by-step synthesis, thus offering much scope for future work on samples incorporating perdeuterated residues.