The Three-Dimensional Structure of an Olfactory Receptor

Researchers have long sought to see in detail how the interaction between receptor and odor molecules plays out. Researchers think that human noses possess about 400 types of olfactory receptors, which are tasked with detecting a vastly larger number of odoriferous volatiles. One recent estimate put the number of possible odor bearing compounds out 40 billion or more. The complexity of the chemistry that the nose detects has made olfaction particularly difficult to explain.