Widespread polybrominated diphenyl ethers (PBDEs) contamination poses risks to human health and ecosystems. Bioremediation is widely considered to be a less ecologically disruptive strategy for remediation of organohalide contamination, but bioremediation of PBDE-contaminated sites is limited by a lack of knowledge about PBDE-dehalogenating microbial populations. Here we report anaerobic PBDE debromination in microcosms established from geographically distinct e-waste recycling sites. Complete debromination of a penta-BDE mixture to diphenyl ether was detected in 16 of 24 investigated microcosms; further enrichment of these 16 microcosms implicated microbial populations belonging to the bacterial genera Dehalococcoides, Dehalogenimonas, and Dehalobacter in PBDE debromination. Debrominating microcosms tended to contain either both Dehalogenimonas and Dehalobacter or Dehalococcoides alone. Separately, complete debromination of a penta-BDE mixture was also observed by axenic cultures of Dehalococcoides mccartyi strains CG1, CG4, and 11a5, suggesting that this phenotype may be fairly common amongst Dehalococcoides. PBDE debromination in these isolates was mediated by four reductive dehalogenases not previously known to debrominate PBDEs. Debromination of an octa-BDE mixture was less prevalent and less complete in microcosms. The PBDE reductive dehalogenase homologous genes in Dehalococcoides genomes represent plausible molecular markers to predict PBDE debromination in microbial communities via their prevalence and transcriptions analysis.

广泛的多溴二苯醚（PBDE）污染对人类健康和生态系统构成风险。生物修复被广泛认为是一种对生态破坏较小的有机卤化物污染修复策略，但由于缺乏对 PBDE 脱卤微生物种群的了解，PBDE 污染场地的生物修复受到限制。在这里，我们报告了在地理位置不同的电子废物回收站建立的微观世界中的厌氧 PBDE 脱溴。在 24 个研究的微观世界中，有 16 个检测到五溴二苯醚混合物完全脱溴为二苯醚；对这 16 个微观世界的进一步富集表明，属于Dehalococcoides、Dehalogenimonas和Dehalobacter细菌属的微生物种群参与了 PBDE 脱溴反应。脱溴微观世界往往含有脱卤单胞菌和脱卤杆菌，或单独含有脱卤球菌。另外，在Dehalococcoides mccartyi菌株 CG1、CG4 和 11a5 的无菌培养物中也观察到五溴二苯醚混合物的完全脱溴，表明这种表型在Dehalococcoides中可能相当常见。这些分离株中的 PBDE 脱溴是由四种还原性脱卤酶介导的，之前未知这些还原脱卤酶可以脱溴 PBDE。八溴二苯醚混合物的脱溴在微观世界中不太普遍且不太完全。Dehalococcoides基因组中的 PBDE 还原脱卤酶同源基因代表了通过其流行率和转录分析来预测微生物群落中 PBDE 脱溴的合理分子标记。