Fig. 7

Isoprene production rates by different Synechocystis strains, which carry the ispS gene under the control of different promoters (see Table 1), in the open-cultivation system at 0 % NaCl. Isoprene production, measured by SPI-MS system, is expressed in relation to optical density (OD₇₅₀; a measure of cell density) over 24 h of phototrophic growth. Mean values and standard deviation from three independent growth experiments with each two technical replicates are shown. Statistical significant differences (***p < 0.001) to the strain # 642 are marked by asterisk