MOE Laboratory of Biosystem Homeostasis and Protection, College of Life Sciences, Zhejiang University, Hangzhou, 310058, PR China.
MOE Laboratory of Biosystem Homeostasis and Protection, College of Life Sciences, Zhejiang University, Hangzhou, 310058, PR China. Electronic address: http://
Chemosphere. 2019 Sep;231:173-183. doi: 10.1016/j.chemosphere.2019.05.137. Epub 2019 May 19.
Our understanding of the tetrahydrofuran (THF) degradation in complex environment is limited. The majority of THF degrading genes reported are group V soluble diiron monooxygenases and share greater than 95% homology with one another. In this study, we used sole-carbon-source incubation combined with high-throughput metagenomic sequencing to investigate this contaminant's degradation in environmental samples. We identified as-yet-uncultivated microbe from the genera Pseudonocardia and fungi Scedosporium sp. (Scedosporium sp. was successfully isolated) as THF degraders as containing THF degradation genes, while microbes from the genera Bordetella, Pandoraea and Rhodanobacter functioned as main cooperators by utilizing acidic intermediates and providing anti-acid mechanisms. Furthermore, a 9387-bp THF degradation cluster designated thmX from the as-yet-uncultivated Pseudonocardia (with 6 main ORFs and with 79-93% amino acid sequence identity with previously reported clusters) was discovered. We also found a THF-degrading related cytochrome P450 monooxygenase from the genus Scedosporium and predicted its cognate reductase for the first time. All the genes and clusters mentioned above were successfully amplified from samples and cloned into the suitable expression vectors. This study will provide novel insights for understanding of THF degradation mechanisms under acid stress conditions and mining new THF degradation genes.
我们对四氢呋喃（THF）在复杂环境中的降解了解有限。大多数报道的 THF 降解基因属于 V 组可溶性二铁单加氧酶，彼此之间具有大于 95%的同源性。在这项研究中，我们使用单一碳源孵育结合高通量宏基因组测序来研究环境样品中这种污染物的降解。我们从诺卡氏菌属和枝顶孢属真菌（成功分离出枝顶孢属真菌）中鉴定出尚未培养的微生物作为 THF 降解菌，它们含有 THF 降解基因，而博德特氏菌属、潘多拉菌属和罗达杆菌属的微生物则通过利用酸性中间产物并提供抗酸机制作为主要的合作者。此外，我们还从尚未培养的假诺卡氏菌属中发现了一个 9387 碱基对的 THF 降解簇，命名为 thmX（有 6 个主要的 ORF，与先前报道的簇有 79-93%的氨基酸序列同一性）。我们还首次从枝顶孢属中发现了一个与 THF 降解相关的细胞色素 P450 单加氧酶，并预测了其对应的还原酶。上述所有基因和簇均成功地从样品中扩增出来，并克隆到合适的表达载体中。这项研究将为在酸性胁迫条件下理解 THF 降解机制和挖掘新的 THF 降解基因提供新的见解。
