摘要
将含有三叶草条基因的重组质粒pT2TFXK和pT2TX3K以接合转移的方式导入快生型大豆根瘤菌H12－2。转移接合子H12－2（pXK）能产三叶草素并具有抑菌活性；H12－2（P3K）表现出对三叶草素的抗性。抑菌谱试验结果表明：82％的供试快生型大豆根瘤菌菌株对三叶草素敏感；所有供试慢生型大豆根瘤菌则表现抗性。稳定性检测结果表明：在共生与人工培养条件下，导入的pXK和p3K质粒均可在宿主菌中稳定存在和表达。
wo plasmids, pT2TFXK (or pXK) and PT2TX3K (p3K) containing tfx genes weretransfered into S. fredii H12 - 2 by transconjugant.One transconjugant, H12 - 2 (pXK), could produce trifolitoxin and form a growth in-hibition zone against trifolitoxin - sensitive strains. The other transconjugant, H12 - 2(p3K), showed resistance to trifolitoxin, but faired to produce it.82% of 100 tested strains of S. fredii were sensitive to trifolitoxin produced by Hl2 -2 (pXK), while all 19 tested strains of Bradyrhizobium japonicum were resistant.The results of stability experiments showed that: either pXK or p3K could stablely in-herited in S. fredii H12 - 2 in the free - living and symbiotic conditions.
出处
《微生物学杂志》
CAS
CSCD
1998年第2期7-12,共6页
Journal of Microbiology
基金
国家科委863高技术研究发展计划经费资助
