A strain of the bacterium Serratia marcescens, isolated from sewage sludge, can oxidise the terpene hydrocarbon α-pinene to produce rans-verbenol as the major product, with verbeone and trans-sobrerol as minor products. A change in nitrogen source and inclusion of glucose as a second carbon source caused the bacterium to produce α-terpineol as the major oxidation product. Products were identified by gas liquid chromatography and mass spectrometry.