Enzymatic oxidation of aromatics with recombinant organisms expressing toluene dioxygenase (TDO) provides valuable synthons for asymmetric synthesis. Several hundreds of cyclohexadiene cis-diols are already known 1 and many have found application in total synthesis of natural products. 1c and 2 Reliable procedures have been published for the whole-cell fermentation of arenes using either a recombinant organism 3 (Escherichia coli JM 109 pDTG601) or a ...