From a molecule towards an odour: the molecular basis of the first olfactory steps

From a molecule towards an odour: the molecular basis of the first olfactory steps. The 2004 Nobel Prize in medicine or physiology awarded the 1991 discovery of the American scientists Richard Axel and Linda Buck on the olfactory receptor gene family and the first levels of data processing by the olfactory system. We take the opportunity of this highlight given to researches devoted to the study of olfaction to get a progress report, originating a better knowledge of the molecular aspects of chemoreception, from chemistry to cognitive sciences, through molecular biology, physiology and neurophysiology. Starting with the description of odorant molecules, we recall the first classical approaches, such as odour/structure relationships. In order to tackle the chemoreception of the sense of smell, we will then describe the olfactory system's physiology and the interaction between odorants and receptors, focusing more particularly on the resulting combinatorial aspects of the coding scheme. Finally, we discuss the consequences on the chemists' community of the knowledge recently acquired about olfaction, predicting some potential applications. Such a multi-disciplinary and fundamental field of research could potentially originate numerous applications, where chemists of all specialities will have to play a crucial role.