- Trehalose mycolates are fundamental characteristics of the outer membrane (mycomembrane) of Mycobacterium tuberculosis and they are supposed to play a key role in the low permeability and high resistance of mycobacteria to many antibiotics; however, still, the molecular characteristics making mycolates so effective in their biological function are not fully understood. This work aims to investigate by quasi-elastic neutron scattering the diffusive dynamical properties of trehalose mycolates in water mixtures as a function of temperature, energy and exchanged wavevector Q in order to elucidate the dynamics-function relation in the mycomembrane. A comparison with lecithin lipids in water mixtures is performed since they are considered among the most rigid and resistant lipids. From the analysis of the data collected as a function of temperature, a lower temperature dependence of the mobility as well as a higher rigidity of trehalose mycolates in comparison with lecithin lipids are highlighted. The present findings provide detailed molecular information which allows to go ahead in the understanding at a molecular level of the resistance to stress and antibiotics by corynebacteria and mycobacteria. |