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Low nitrogen minimal medium (per liter, 2.0 g KH2PO4, 1.18 g succinic acid, 0.1 g NH4SO4, pH adjusted to 7.0 with solid KOH, after autoclaving add 20 ml of sterilized 2% MgSO4) was used in experiments with A. calcoaceticus strain BD413 to induce wax ester formation. High nitrogen minimal medium was the same as the above except that it also contained 1.0 g NH4SO4 per liter. For other purposes such as DNA isolation, A. calcoaceticus was grown and maintained on LB medium (10 g bactotryptone, 5 g bacto-yeast extract and 10 g NaCl per liter, pH 7.0). For chemical feeding experiments in which compounds such as hexadecane, hexadecanol and cis-11-hexadecenal were provided as carbon sources, the above minimal media were used with the addition of 0.3% of the substrate. Hexadecane and hexadecanol were sonicated for approximately 2 minutes in the media to generate a suspension. A. calcoaceticus cultures were typically grown overnight at 30° C. In the case of larger volume cultures(i.e. 50 mls and larger), 3 ml overnight cultures were collected by centrifugation, the cell pellet was washed in new media, recentrifuged and then added to the fresh media, before being incubated at 30° C. overnight. Maintenance and growth of Escherichia coli stains was on LB with appropriate antibiotics. Antibiotics were used in the following concentrations: Ampicillin 100 μg/ml, Chloramphenicol 50 μg/ml, Kanamycin 25 μg/ml, Rifampicin 50 μg/ml and Tetracycline 15 μg/ml.