title: Molecular characterization of microbial mutations induced by ion beam irradiation.
abstract: A positive selection system for gene disruption using a sucrose-sensitive transgenic rhizobium was established and used for the molecular characterization of mutations induced by ion beam irradiations. Single nucleotide substitutions, insertions, and deletions were found to occur in the sucrose sensitivity gene, sacB, when the reporter line was irradiated with highly accelerated carbon and iron ion beams. In all of the insertion lines, fragments of essentially the same sequence and of approximately 1188bp in size were identified in the sacB regions. In the deletion lines, iron ions showed a tendency to induce larger deletions than carbon ions, suggesting that higher LET beams cause larger deletions. We found also that ion beams, particularly "heavier" ion beams, can produce single gene disruptions and may present an effective alternative to transgenic approaches.
authors: Graduate School of Science and Technology, Chiba University, Matsudo, Chiba 271-8510, Japan. ichida@riken.jp
authors: Hiroyuki
authors: H
authors: Ichida
authors: Tomoki
authors: T
authors: Matsuyama
authors: Hiromichi
authors: H
authors: Ryuto
authors: Yoriko
authors: Y
authors: Hayashi
authors: Nobuhisa
authors: N
authors: Fukunishi
authors: Tomoko
authors: T
authors: Abe
authors: Takato
authors: T
authors: Koba
mesh_terms: D001483:Base Sequence; D004252:DNA Mutational Analysis; D004269:DNA, Bacterial / Q000528:radiation effects; D020450:Heavy Ions / Q000009:adverse effects; D008969:Molecular Sequence Data; D009154:Mutation / Q000528:radiation effects*; D011829:Radiation Dosage; D011839:Radiation, Ionizing; D012231:Rhizobium / Q000235:genetics* / Q000528:radiation effects*
chemical_list: D004269:DNA, Bacterial