Genome analysis of a high temperature tolerant mutant of USDA110 generated by ion-beam irradiation

Takeda, Kiyoko; Sato, Katsuya; Narumi, Issey*; Otsu, Naoko*; Yokoyama, Tadashi*

With the aims of utilization as a biofertilizer inoculant and elucidation of high-temperature tolerance mechanism of soybean nodule bacteria, we had applied the ion beam breeding technology to a strain () USDA110. Consequently, we obtained a mutant named M14 which was able to maintain high viable cell numbers under high-temperature (42 degrees) for at least 7 days. Genome comparison with USDA110 revealed that (1) 1.27 Mbp inversion mutagenesis and (2) 18 single base mutations were occurred in M14. This study was the first attempt to apply the ion beam breeding technology to a prokaryote and succeeded in proving the effectiveness of it.