Promoter activity in developing spores. Derivatives of S. coelicolor strain M145 carrying different putative promoters fused to a promoterless mCherry were grown on MS agar to form spores. Spores were analyzed by phase contrast (left panel) and fluorescence microscopy (right panel), to detect the mCherry signal derived from activity of the specific promoters. As controls for hyphal autofluorescence, strain M145 carrying the empty vector pKF210 (A) was also investigated. The investigated putative promoter regions are localized immediately upstream of genes SCO0934 (B), SCO1773 (C), SCO1774 (D), SCO3857 (E), SCO4157 (F), SCO4421 (G), and SCO7449 (H). Representative images are shown here, and quantitative analysis in Table 1. Scale bar, 4μm.