Incubations of isotopically pure [2-(2)H(1)](E,E)-farnesyl diphosphate with recombinant patchoulol synthase (PTS) from Pogostemon cablin afforded a 65:35 mixture of monodeuterated and dideuterated patchoulols as well as numerous sesquiterpene hydrocarbons. Extensive NMR analyses ((1)H and (13)C NMR,