||P.453 right column 2nd paragraph: "Elemental Composition and Heat of Combustion of the Dry Biomass: The elemental composition of the cells showed small variations during batch growth between different physiological states (data not shown). Consequently, the heat of combustion values, calculated from the elemental composition (refs 9, 14) , showed a small standard deviation (SD ±0.38 kJ/g(af) dry weight, n = 4), which were within the same range as for the standard deviation between parallel samples from a specific physiological state (see below). This variation in the heat of combustion of the biomass affected the energy balance calculations by maximally 1%. Therefore, the experimentally determined heat of combustion value of -21.39±0.33 kJ/g(af) dry weight (±SD, n = 4) of stationary phase cells has been used for all energy balance calculations. The corresponding elemental composition of stationary phase cells (CH1.71O0.52N0.17), which gives a unit carbon formula weight (UCFW) of 24.4 g/C-mol, was used in the continuous substrate and product calculations presented later. These values are in agreement with data previously reported in the literature (refs 5, 9)."