<P><B>Abstract</B></P> <P>Butane is an abundant side product of oil and gas production and is mostly burned for energy and heat production. The alkane monooxygenase enzyme system <I>AlkBGT</I> expressed in <I>E. coli</I> offers a robust model system with a fast butane uptake for microbial oxidation at low temperatures (25–40 °C) and pressures (1.1–1.5 bar). The process is established in a two liter bubble column under strict safety requirements obligatory for butane/air mixtures. Detailed characterization of the transport limited process regarding the relevant process parameters gassing rate / superficial velocity (0.25–1.5 L·min<SUP>−1</SUP>/ 0.8 – 5 cm·s<SUP>−1</SUP>), butane content (14–28 % v/v), pressure as well as temperature is carried out. Classical k<SUB>L</SUB>a-transferability is shown inside the selected process window. The determined optimum (1.5 L·min<SUP>−1</SUP>/ 5 cm·s<SUP>−1</SUP>; 1.5 bar; 35 °C and 14 % v/v) is validated and a first scale up to 5 L is approximated. The potential is discussed as a first step to a fermentative oxidation of butane on industrial scale.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Volumetric productivity is driven by butane gas to liquid mass transfer. </LI> <LI> Gassing rate dominates volumetric productivity over pressure and temperature. </LI> <LI> Increasing butane content is no key to significantly rise volume productivity. </LI> <LI> k<SUB>L</SUB>a transferability demonstrated for different bubble column geometries. </LI> </UL> </P>