[Intrinsic luminescence and differentiation in Actinomyces lucensis--producer of etruscomycin].

The luminescence of Actinomyces lucensis producing etruscomycin was found to be caused not by the antibiotic but by additional luminescent substances. No direct correlation has been established between the content of the luminescent substances and the intensity of the luminscence. The latter depends on the differentiation of the colonies, i.e. on the presence of a dark layer that screens the luminescence of the colonial mycelium and is localized under the aerial mycelium. The dark layer contains pigments of the melanin type.