Intraspecific variation in gamma-radiation resistance and genomic structure in the filamentous fungus Alternaria alternata: A case study of strains inhabiting Chernobyl reactor No. 4

This is probably the first report on intraspecific variation in radiation r esistance for filamentous fungi. It was revealed that natural (" field") st rains of the filamentous fungus Alternaria alternata are extremely variable in response to gamma-irradiation ranging from supersensitive to highly res istant to radiation. At the same time nearly all strains originating from t he highly radiation-polluted reactor of the Chernobyl (Ukraine) Nuclear Pow er Plant possessed high radiation resistance. The genome structure of strai ns studied by universally primed polymerase chain reaction (UP-PCR) was fou nd to be well conserved in " reactor " but not in "control" strains. The "r eactor" strains appear to be genetically adapted to this high radiation hab itat by means of selection, thus providing a natural source of genetically homogeneous fungal lineages. (C) 2000 Academic Press.