The key role of chlorocatechol 1,2-dioxygenase in phytoremoval and degradation of catechol by transgenic arabidopsis
The key role of chlorocatechol 1,2-dioxygenase in phytoremoval and degradation of catechol by transgenic arabidopsis
复制标题
DOI：
10.1104/pp.106.085936
复制
发表时间：
2006-10-01
期刊：
影响因子：
7.4
通讯作者：
Kuai, Benke
中科院分区：
文献类型：
--
作者：
Liao, Yang;Zhou, Xiao;Kuai, Benke
利用植物中的细菌降解基因来降解环境中的有机污染物已被认为是一种有利的策略。这些污染物的芳香环特性是它们难以降解的主要原因。在这项研究中，邻单胞菌衍生的氯儿茶酚1，2-双加氧酶（TfdC）基因（tfdC），能够切割的芳香环，被引入到拟南芥（拟南芥）。转基因植物的形态和生长与野生型植物没有区别。相反，它们显示出对邻苯二酚的显著增强的耐受性。转基因植物还表现出显著更高的从其培养基中去除儿茶酚的能力和将儿茶酚转化为顺式，顺式-粘康酸的高效率。由于远低于计算量的顺式，顺式粘康酸内积累的转基因植物，存在的内源性TfdD和TfdE样的活动被假定，随后，推定的直向同源物的细菌tfdD和tfdE在拟南芥中检测。然而，没有TfdC活性，也没有鉴定出tfdC或tfdF的推定直系同源物。这项工作表明，TfdC活性，赋予转基因拟南芥中的tfdC，是植物去除和降解邻苯二酚的关键要求，也表明，微生物降解基因可能被转基因利用植物中的芳香族污染物的生物修复环境中。
Transgenic exploitation of bacterial degradative genes in plants has been considered a favorable strategy for degrading organic pollutants in the environment. The aromatic ring characteristic of these pollutants is mainly responsible for their recalcitrance to degradation. In this study, a Plesiomonas-derived chlorocatechol 1,2-dioxygenase (TfdC) gene (tfdC), capable of cleaving the aromatic ring, was introduced into Arabidopsis (Arabidopsis thaliana). Morphology and growth of transgenic plants are indistinguishable from those of wild-type plants. In contrast, they show significantly enhanced tolerances to catechol. Transgenic plants also exhibit strikingly higher capabilities of removing catechol from their media and high efficiencies of converting catechol to cis, cis-muconic acid. As far-less-than-calculated amounts of cis, cis-muconic acid were accumulated within the transgenic plants, existence of endogenous TfdD- and TfdE-like activities was postulated and, subsequently, putative orthologs of bacterial tfdD and tfdE were detected in Arabidopsis. However, no TfdC activity and no putative orthologs of either tfdC or tfdF were identified. This work indicates that the TfdC activity, conferred by tfdC in transgenic Arabidopsis, is a key requirement for phytoremoval and degradation of catechol, and also suggests that microbial degradative genes may be transgenically exploited in plants for bioremediation of aromatic pollutants in the environment.