The heterologous production of the industrially relevant fungal enzyme pyranose 2-oxidase in the prokaryotic host E. coli was investigated using 3 different expression systems, i.e. the well-studied T7 RNA polymerase based pET21d+, the L-arabinose inducible pBAD and the pCOLD system. Preliminary experiments were done in shaking flasks at 25C and optimized induction conditions to compare the productivity levels of the different expression systems. The pET21d+ and the pCOLD system gave 29 U/L·h and 14 U/L·h of active pyranose 2-oxidase, respectively, whereas the pBAD system only produced 6 U/L·h. Process conditions for batch fermentations were optimized for the pET21d+ and the pCOLD systems in order to reduce the formation of inactive inclusion bodies. The highest productivity rate with the pET21d+ expression system in batch fermentations was determined at 25C with 32 U/L·h. The pCOLD system showed the highest productivity rate (19 U/L·h) at 25C and induction from the start of the cultivation. Using the pCOLD system in a fed batch fermentation at 25C with a specific growth rate of = 0.15 h-1resulted in the highest productivity rate of active pyranose oxidase with 206 U/L·h.