Patent ID: 7223550

Claim:
A biosensor comprising a yeast expressing the following elements: (a) at least one olfactory receptor protein for binding olfactant; (b) at least one exogenous signaling pathway coupled to the at least one olfactory receptor for transducing a signal produced by the at least one olfactory receptor upon olfactant binding; and (c) at least one signal reporter coupled to the signaling pathway for producing a detectable phenomenon upon transduction of the olfactant binding signal by the signaling pathway, wherein the at least one olfactory receptor protein comprises: (i) an olfactory receptor hypervariable segment which contains at least one olfactant binding site; (ii) a processing/transport segment which directs the processing and transport of the receptor in the yeast, wherein the processing/transport segment is located N-terminal to the olfactory receptor hypervariable segment; and (iii) a coupling segment which couples the receptor to the at least one exogenous signaling pathway in the yeast, wherein the coupling segment is located C-terminal to the olfactory receptor hypervariable segment.