FIG. 1.
Carotenoid production by S. coelicolor A3(2). (A) Colonies of wild-type S. coelicolor harboring pKM284. Colonies grown for 4 days on Bennett's glucose solid medium under light and dark conditions are shown. This strain is defective in the production of blue- and red-pigmented antibiotics due to the unknown effect of pKM284; consequently, it clearly exhibits the accumulation of yellow carotenoid pigments in the cells. (B) UV-visible spectrum of the purified carotenoid fraction extracted from S. coelicolor wild-type cells grown for 2 days under light (red line) and dark (black line) conditions. The same fraction extracted from the crtEIBV mutant cultured under light conditions was also analyzed (blue line). (C) Thin-layer chromatography analysis of the purified carotenoid fraction from S. coelicolor wild-type cells grown for 2 days under blue light illumination. The spots identified as β-carotene (Rf = 0.54) (b) and isorenieratene (Rf = 0.24) (i) by HPLC analysis are indicated.