Effect of light on germinating spores of Streptomyces viridosporus

Our study showed that the effect of light on germinating spores of Streptom yces was variable: some species were indifferent, whereas others, such as S treptomyces viridosporus, displayed a marked inhibition of CFU numbers on g rowth medium. A special study with S. viridosporus showed that light only h ad an impact during the first few hours of spore incubation. The effects of scavengers of toxic forms of oxygen and of photosensitizers, along with th e oxidative stress of illuminated spores evidenced by the superoxide dismut ase levels, suggested that light and oxygen had a combined action. (C) 1999 Federation of European Microbiological Societies. Published by Elsevier Sc ience B.V. All rights reserved.