Wu Yuejin

Transferring Gus gene into intact rice cells by low energy ion beam

Abstract A new technique of transferring genes by low energy ion beam has been reported in this paper. The Gus and CAT (chloramphenicol acetyltransferase) genes, as “foreign” genetic materials, were introduced into the suspension cells and ripe embryos or rice by implantation of 20–30 keV Ar + at doses ranging from 1 × 10 15 to 4 × 10 15 ions/cm 2 . The activities of CAT and Gus were detected in the cells and embryos after several weeks. The results indicate that the transfer was a success.

Mutagenic Effects of BM302:GO112 Induced by Low-Energy Ion Beam Implantation

Mutant strains of GO112 and BM302 with a high 2-keto-L-gulonic acid (2KLG) transformation rate induced by ion beam implantation were separately and combinatorially compared with the original strains GO29 and BM80 to study the mutagenic effects of ion beam implantation. Both the sole GO112 and mixed BM302:GO112 demonstrated improved SNDH activity and 2KLG yield compared to the original strains. The mutant combinations of BM302:GO112 showed a longer stationary phase and higher biomass than BM80:GO29. The mutant BM302 exhibited a stronger capacity to maintain a stable pH environment at mixed fermentation with Gluconobacter oxydans (G. oxydans) for 2KLG transformation and facilitated the growth of G. oxydans compared with the original strain BM80. The promotive capacity to L-sorbosone dehydrogenase (L-SNDH) from the supernate of BM302 was 1.6-fold higher than that of BM80. Genes encoded SNDH in GO29 and GO112 were amplified and sequenced, and mutations including three transitions (CG → TA, CG → TA, GC → AT) and one transversion (AT → TA) were confirmed from GO29 to GO112. The corresponding amino acid was changed as Leu → Phe, Arg → Gln and Asn → Lys.