The acquisition of indigenous plasmids by a genetically marked pseudomonad population colonizing the sugar beet phytosphere is related to local environmental conditions
The acquisition of indigenous plasmids by a genetically marked pseudomonad population colonizing the sugar beet phytosphere is related to local environmental conditions
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DOI：
10.1128/aem.63.4.1577-1583.1997
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发表时间：
1997-04-01
影响因子：
4.4
通讯作者：
Bailey, MJ
中科院分区：
文献类型：
--
作者：
Lilley, AK;Bailey, MJ
已经观察到天然存在的接合质粒从土著微生物区系转移到定殖于植物的植圈的遗传修饰的细菌群体。标记的菌株（荧光假单胞菌SBW 25 EeZY 6 KX）作为种子敷料甜菜（甜菜变种，紫水晶）作为田间试验的一部分，以评估故意释放的细菌接种物的生态和遗传稳定性。持续的人口引进的菌株，其中殖民化的植物圈，在整个生长季节进行了评估收购的质粒赋予耐汞性（汞-r）。Transconjugants分离，只有从根和叶样品收集在一个狭窄的时间窗口内与作物的季节成熟，共轭转移事件记录在这段时间内在两个独立的田间释放实验进行了连续的西尔斯。有一次，9株植物中有7株支持转接合子荧光假单胞菌SBW 25 EeZY 6 KX，这表明在特定的环境条件下，植物圈中细菌种群之间的接合基因转移可能是一种常见的事件。通过定殖接种物原位获得的质粒被鉴定为限制性消化模式组I、III或TV质粒的天然变体，所述质粒来自已知持续存在于田间甜菜植物圈中的5个遗传上不同的大的接合性汞抗性质粒组，这些数据表明，不仅基因转移可能是一个共同的事件，而且接种物的遗传和表型稳定性释放到自然界中，环境无法预测。
The transfer of naturally occurring conjugative plasmids from the indigenous microflora to a genetically modified population of bacteria colonizing the phytospheres of plants has been observed. The marked strain (Pseudomonas fluorescens SBW25EeZY6KX) was introduced as a seed dressing to sugar beets (Beta vulgaris var, Amethyst) as part of a field experiment to assess the ecology and genetic stability of deliberately released bacterial inocula. The sustained populations of the introduced strain, which colonized the phytosphere, were assessed throughout the growing season for the acquisition of plasmids conferring mercury resistance (Hg-r). Transconjugants were isolated only from root and leaf samples collected within a narrow temporal window coincident with the midseason maturation of the crop, Conjugal-transfer events were recorded during this defined period in two separate field release experiments conducted over consecutive Sears. On one occasion seven of nine individual plants sampled supported transconjugant P. fluorescens SBW25EeZY6KX, demonstrating that conjugative gene transfer between bacterial populations in the phytosphere may be a common event under specific environmental conditions. The plasmids acquired in situ by the colonizing inocula were identified as natural variants of restriction digest pattern group I, III, or TV plasmids from five genetically distinct groups of large, conjugative mercury resistance plasmids known to persist in the phytospheres of sugar beets at the field site, These data demonstrate not only that gene transfer may be a common event but also that the genetic and phenotypic stability of inocula released into the natural environment cannot be predicted.