Environmental and Developmental Regulation of Carotenogenesis in the Dimorphic Fungus Mucor rowcii

摘要

Aerobic mycelium of wild-type Mucor roudi accumulated about ten times higher amounts of the carotenoid pigment β-carotene when grown continuously in the presence of light than the corresponding cultures grown in the dark. Carotenoid accumulation wasdependent on light intensity, with the threshold located at about 10~(-2) W.m~(-2). Photocarotenogenesis in complex medium was more efficient with glucose as a carbon source. Caiotenoid synthesis by M. rowdi mycelium was unaffected by both retinol acetate and retinal, which are stimulators of carotenogen-esis in other zygomycetes. Carotenogenesis was significant in aerobic mycelium but was almost undetectable in anaerobic mycelium as well as in aerobic or anaerobic yeast cells, This suggested an involvement of oxygen in carotenoid synthesis by M. rowdi and the existence of developmental regulation of the expression or operation of the pathway.