Nielsen K M, van Elsas J D, Smalla K
Unigen and Department of Botany, Norwegian University of Science and Technology, 7491 Trondheim, Norway.
Appl Environ Microbiol. 2000 Mar;66(3):1237-42. doi: 10.1128/AEM.66.3.1237-1242.2000.
Here we show that horizontal transfer of DNA, extracted from transgenic sugar beets, to bacteria, based on homologous recombination, can occur in soil. Restoration of a 317-bp-deleted nptII gene in Acinetobacter sp. strain BD413(pFG4) cells incubated in sterile soil microcosms was detected after addition of nutrients and transgenic plant DNA encoding a functional nptII gene conferring bacterial kanamycin resistance. Selective effects of the addition of kanamycin on the population dynamics of Acinetobacter sp. cells in soil were found, and high concentrations of kanamycin reduced the CFU of Acinetobacter sp. cells from 10(9) CFU/g of soil to below detection. In contrast to a chromosomal nptII-encoded kanamycin resistance, the pFG4-generated resistance was found to be unstable over a 31-day incubation period in vitro.
在此我们表明,基于同源重组,从转基因甜菜中提取的DNA向细菌的水平转移可在土壤中发生。在无菌土壤微宇宙中培养的不动杆菌属菌株BD413(pFG4)细胞中,添加营养物质和编码赋予细菌卡那霉素抗性的功能性nptII基因的转基因植物DNA后,检测到缺失317 bp的nptII基因得以恢复。发现添加卡那霉素对土壤中不动杆菌属细胞群体动态有选择作用,高浓度卡那霉素使不动杆菌属细胞的菌落形成单位从每克土壤10⁹ CFU降至检测限以下。与染色体编码的nptII卡那霉素抗性不同,发现pFG4产生的抗性在体外31天的培养期内不稳定。