The conversion of 2-phenoxyethanol to phenol and acetate by the anaerobic bacterium Acetobacterium sp. strain LuPhet1 proceeds through acetaldehyde with concomitant migration of a H-atom from C(1) to C(2) of the glycolic moiety. Separate feeding experiments with (R)- and (S)-2-phenoxy(1-2H)ethanol, prepared via chemoenzymatic syntheses, indicate that the H-atom involved in the 1,2-shift is the pro-S one of the enantiotopic couple of the alcohol function.