title: Mutagenic effects of heavy ions in bacteria.
abstract: Various mutagenic effects by heavy ions were studied in bacteria, irradiated at accelerators in Dubna, Prague, Berkeley or Darmstadt. Endpoints investigated are histidine reversion (B. subtilis, S. typhimurium), azide resistance (B. subtilis), mutation in the lactose operon (E. coli), SOS chromotest (E. coli) and lambda-prophage induction (E. coli). It was found that the cross sections of the different endpoints show a similar dependence on energy. For light ions (Z < or = 4) the cross section decreases with increasing energy. For ions of Z = 10, it is nearly independent of energy. For heavier ions (Z > or = 26) it increases with energy up to a maximum or saturation. The increment becomes steeper with increasing Z. This dependence on energy suggests a "mutagenic belt" inside the track that is restricted to an area where the density of departed energy is low enough not to kill the cell, but high enough to induce mutations.
authors.affiliation: DLR, Institute of Aerospace Medicine, Biophysics Division, Koln, Germany.
authors.forename: G
authors.initials: G
authors.lastname: Horneck
authors.forename: E A
authors.initials: EA
authors.lastname: Krasavin
authors.forename: S
authors.initials: S
authors.lastname: Kozubek
mesh_terms: D001386:Azides / Q000494:pharmacology; D001412:Bacillus subtilis / Q000235:genetics / Q000528:radiation effects*; D003359:Cosmic Radiation; D017357:Cyclotrons; D004307:Dose-Response Relationship, Radiation; D004926:Escherichia coli / Q000235:genetics / Q000528:radiation effects*; D005798:Genes, Bacterial / Q000528:radiation effects; D006639:Histidine / Q000528:radiation effects; D007763:Lac Operon / Q000528:radiation effects; D018499:Linear Energy Transfer; D016296:Mutagenesis / Q000528:radiation effects*; D009153:Mutagens; D009154:Mutation / Q000187:drug effects / Q000528:radiation effects; D010315:Particle Accelerators; D011836:Radiation Tolerance; D011839:Radiation, Ionizing; D013014:SOS Response, Genetics; D012486:Salmonella typhimurium / Q000235:genetics / Q000528:radiation effects*; D019810:Sodium Azide; D013171:Spores, Bacterial / Q000528:radiation effects
chemical_list: D001386:Azides; D009153:Mutagens; D006639:Histidine; D019810:Sodium Azide