Photoinduction of carotenoid biosynthesis inGibberella fujikuroi

Carotenoid biosynthesis is photoinducible in Gibberella fujikuroi, an organism used in the fermentive production of the gibberellins. The light exposed needed for an appreciable response is higher than those required for other fungi, such as Fusarium aquaeductuum and Neurospora crassa, under identical conditions. Time course of the accumulation of carotenoids is very similar to that for Fusarium aquaeductuum. Growth in one of the culture media used increases the carotenoid content in the dark but does not affect photoinduction. Three mutants with enhanced carotenoid synthesis in the dark show the same response to light as the wild-type. Our results suggest that photoinduction of carotenogenesis in Gibberella fujikori is independent of the carotenoid content already present in dark-grown cultures.