In order to elucidate the role of trehalose in conferring to the mycomembrane of corynebacteria and mycobacteria its extraordinary stability and rigidity and then to go ahead in the understanding of the molecular cofactors responsible for the resistance and virulence of these bacteria, we propose to use the IN4 spectrometer for investigating the dynamical properties of different mixtures of mono- and di-mycolates of glucose and trehalose. More specifically, since trehalose is a disaccharide composed by two glucose units linked by an Ñ-Ñ C1-C1 glycosidic bond, the systems to be investigated are: trehalose monomycolates/trehalose dimycolates at a ratio of 1:1, trehalose monomycolates/glucose monomycolates at a ratio of 1:2. By taking into account that we will collect data on 4 samples at the 5 temperature values of 20-140-260-300-340K (about 4 hours for each temperature), the calibration runs (empty can, transmission and Vanadium), the sample change and temperature stabilization time, we estimate for the required statistics a total of 5 days of beamtime on IN4.