Conjugative Transfer of Dioxin-Catabolic Megaplasmids and Bioaugmentation Prospects of a Rhodococcus sp
Conjugative Transfer of Dioxin-Catabolic Megaplasmids and Bioaugmentation Prospects of a Rhodococcus sp
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二恶英分解代谢巨质粒的接合转移和红球菌属的生物增强前景
DOI：
10.1021/acs.est.7b00188
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发表时间：
2017
影响因子：
11.4
通讯作者：
Li Li
中科院分区：
文献类型：
--
作者：
Sun Jiao;Qiu Yilun;Ding Pengfei;Peng Peng;Yang Haiyan;Li Li
基因生物强化是一种很有前途的修复二恶英污染环境的策略，它利用携带接合质粒的细菌提供分解代谢功能。本文研究了红球菌（Rhodococcussp.）携带的二恶英分解代谢质粒pDF 01和pDF 02的接合转移。菌株p52。以p52菌株为供体的交配试验表明，pDF 01和pDF 02可同时接合转移到铜绿假单胞菌受体中，接合频率为3 × 10- 4个菌落/受体。pDF 01和pDF 02是从P.通过Southern杂交对铜绿假单胞菌转接合子进行鉴定，并通过荧光原位杂交将它们定位在转接合子细胞中。此外，分解代谢质粒在接合子中起作用，接合子获得了利用二苯并呋喃和氯二苯并呋喃生长的能力，并且它们在50%的接合子细胞中保持了30代而没有选择压力。此外，检测到分解代谢质粒到活性污泥细菌的接合转移。pDF 01和pDF 02的测序揭示了质粒接合转移和稳定维持的遗传基础，以及它们在二恶英催化过程中的协同作用。因此，携带pDF 01和pDF 02的菌株p52具有在二恶英污染环境中进行遗传生物强化的潜力。
Genetic bioaugmentation, in which bacteria harboring conjugative plasmids provide catabolic functions, is a promising strategy to restore dioxin-contaminated environments. Here we examined the conjugative transfer of the dioxin–catabolic plasmids pDF01 and pDF02 harbored byRhodococcussp. strain p52. A mating experiment using strain p52 as a donor showed that pDF01 and pDF02 were concomitantly and conjugatively transferred from strain p52 to aPseudomonas aeruginosarecipient at a conjugation frequency of 3 × 10–4colonies per recipient. pDF01 and pDF02 were isolated from theP. aeruginosatransconjugant and identified by Southern hybridization, and they were localized in the transconjugant cells by fluorescence in situ hybridization. Moreover, the catabolic plasmids functioned in the transconjugant, which gained the ability to use dibenzofuran and chlorodibenzofuran for growth, and they were maintained in 50% of the transconjugant cells for 30 generations without selective pressure. Furthermore, conjugative transfer of the catabolic plasmids to activated sludge bacteria was detected. Sequencing of pDF01 and pDF02 revealed the genetic basis for the plasmids’ conjugative transfer and stable maintenance, as well as their cooperation during dioxin catabolism. Therefore, strain p52 harboring pDF01 and pDF02 has potential for genetic bioaugmentation in dioxin-contaminated environments.