The remediation of soil contaminated by 1,1,1-trichloro-2,2-bis(4-chlorophenyl)ethane (DDT) remains an important issue in environmental research. Although our previous studies demonstrated that earthworms could enhance the degradation of DDT in soils, the underlying mechanisms and microorganisms involved in these transformation processes are still not clear. Here we studied the transformation of DDT in sterilized/non-sterilized drilosphere and non-drilosphere matrices and identified DDT degraders using the technique of DNA-stable isotope probing. The results show that DDT degradation in non-sterilized drilosphere was quicker than that in their non-drilosphere counterparts. Earthworms enhance DDT removal mainly by improving soil properties, thus stimulating indigenous microorganisms rather than abiotic degradation or tissue accumulating. Ten new genera, including Streptomyces, Streptacidiphilus, Dermacoccus, Brevibacterium, Bacillus, Virgibacillus, were identified as DDT ring cleavage degrading bacteria in the five matrices tested. Bacillus and Dermacoccus may also play vital roles in the dechlorination of DDTs as they were highly enriched during the incubations. The results of this study provide robust evidence for the application of earthworms in remediating soils polluted with DDT and highlight the importance of using combinations of cultivation-independent techniques together with process-based measurements to examine the function of microbes degrading organic pollutants in drilosphere matrices.

修复被1,1,1-三氯-2,2-双（4-氯苯基）乙烷（DDT）污染的土壤仍然是环境研究中的重要问题。尽管我们先前的研究表明worm可以促进土壤中DDT的降解，但这些转化过程涉及的潜在机制和微生物仍不清楚。在这里，我们研究了DDT在无菌/非无菌小球层和非小球层基质中的转化，并使用DNA稳定同位素探测技术鉴定了DDT降解剂。结果表明，非灭菌小球体中的滴滴涕降解速度要快于非小球体中的滴滴涕。mainly主要通过改善土壤特性，从而刺激本地微生物而不是非生物降解或组织积累，来增强DDT的去除。链霉菌，Streptacidiphilus，Dermacoccus，短杆菌属，芽孢杆菌属，Virgibacillus，被确定为在测试的5点矩阵DDT环切割降解菌。芽孢杆菌和皮肤球菌也可能在DDT的脱氯中起重要作用，因为它们在培养过程中高度富集。这项研究的结果为for在修复被DDT污染的土壤中的应用提供了有力的证据，并强调了结合使用独立于耕作的技术与基于过程的测量方法来检查微生物降解小球层基质中有机污染物的功能的重要性。