Polychlorinated biphenyl (PCB)-degrading bacteria associated with trees in a PCB-contaminated site
Polychlorinated biphenyl (PCB)-degrading bacteria associated with trees in a PCB-contaminated site
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DOI：
10.1128/aem.72.4.2331-2342.2006
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发表时间：
2006-04-01
影响因子：
4.4
通讯作者：
Fletcher, JS
中科院分区：
文献类型：
--
作者：
Leigh, MB;Prouzová, P;Fletcher, JS
为确定能提高土壤中多氯联苯（PCB）微生物降解潜力的植物，对5种自然生长的树木中土著PCB降解菌的丰度、种类和降解能力进行了研究。可培养的PCB降解剂与每一种植物的根际和根区，这被定义为在植物扎根的散装土壤检查。在某些季节和某些土壤深度，在奥地利松（黑松）和山羊杨柳（沙柳）的根区中检测到的PCB降解物数量明显高于其他植物或非根土壤的根区（2.7- 56.7倍）。大多数可培养的PCB降解整个网站和大多数可培养的PCB降解与植物被确定为成员的属红球菌16 S rRNA基因序列分析。多氯联苯降解菌的其他分类群包括Luteibacter属和Williamsia属的成员，这些细菌以前没有被证明包括多氯联苯降解菌。多氯联苯降解试验表明，从网站的一些分离株具有广泛的同源特异性，这些分离株包括一个红球菌菌株表现出类似的降解能力的伯克霍尔德氏菌LB 400。具有广泛同源特异性的分离株在现场广泛分布，包括杨柳的生物刺激根区。某些植物物种与本地多氯联苯降解剂，包括具有突出降解能力的生物体，在整个根区增加丰度的明显关联支持的概念，即通过根修复的生物刺激是一个有前途的战略，提高多氯联苯原位降解。
The abundance, identities, and degradation abilities of indigenous polychlorinated biphenyl (PCB)-degrading bacteria associated with five species of mature trees growing naturally in a contaminated site were investigated to identify plants that enhance the microbial PCB degradation potential in soil. Culturable PCB degraders were associated with every plant species examined in both the rhizosphere and root zone, which was defined as the bulk soil in which the plant was rooted. Significantly higher numbers of PCB degraders (2.7- to 56.7-fold-higher means) were detected in the root zones of Austrian pine (Pinus nigra) and goat willow (Salix caprea) than in the root zones of other plants or non-root-containing soil in certain seasons and at certain soil depths. The majority of culturable PCB degraders throughout the site and the majority of culturable PCB degraders associated with plants were identified as members of the genus Rhodococcus by 16S rRNA gene sequence analysis. Other taxa of PCB-degrading bacteria included members of the genera Luteibacter and Williamsia, which have not previously been shown to include PCB degraders. PCB degradation assays revealed that some isolates from the site have broad congener specificities; these isolates included one Rhodococcus strain that exhibited degradation abilities similar to those of Burkholderia xenovorans LB400. Isolates with broad congener specificity were widespread at the site, including in the biostimulated root zone of willow. The apparent association of certain plant species with increased abundance of indigenous PCB degraders, including organisms with outstanding degradation abilities, throughout the root zone supports the notion that biostimulation through rhizoremediation is a promising strategy for enhancing PCB degradation in situ.