Department of Environmental Biotechnology, Helmholtz Centre for Environmental Research - UFZ, Leipzig, Germany.
The Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, 2800, Kgs, Lyngby, Denmark.
Sci Rep. 2022 Feb 17;12(1):2666. doi: 10.1038/s41598-022-06558-0.
The continuing reports of plastic pollution in various ecosystems highlight the threat posed by the ever-increasing consumption of synthetic polymers. Therefore, Pseudomonas capeferrum TDA1, a strain recently isolated from a plastic dump site, was examined further regarding its ability to degrade polyurethane (PU) compounds. The previously reported degradation pathway for 2,4-toluene diamine, a precursor and degradation intermediate of PU, could be confirmed by RNA-seq in this organism. In addition, different cell fractions of cells grown on a PU oligomer were tested for extracellular hydrolytic activity using a standard assay. Strikingly, purified outer membrane vesicles (OMV) of P. capeferrum TDA1 grown on a PU oligomer showed higher esterase activity than cell pellets. Hydrolases in the OMV fraction possibly involved in extracellular PU degradation were identified by mass spectrometry. On this basis, we propose a model for extracellular degradation of polyester-based PUs by P. capeferrum TDA1 involving the role of OMVs in synthetic polymer degradation.
各种生态系统中不断有塑料污染的报告，这凸显了不断增加的合成聚合物消费所带来的威胁。因此，最近从一个塑料倾倒场分离出的假单胞菌 capeferrum TDA1 被进一步研究其降解聚氨酯（PU）化合物的能力。通过 RNA-seq 可以在该生物中证实先前报道的 2,4-甲苯二胺（PU 的前体和降解中间体）的降解途径。此外，使用标准测定法测试了在 PU 低聚物上生长的细胞的不同细胞级分的细胞外水解活性。惊人的是，在 PU 低聚物上生长的假单胞菌 capeferrum TDA1 的纯化外膜囊泡（OMV）显示出比细胞沉淀更高的酯酶活性。通过质谱鉴定了 OMV 部分中可能参与细胞外 PU 降解的水解酶。在此基础上，我们提出了假单胞菌 capeferrum TDA1 对聚酯基 PU 的细胞外降解模型，涉及 OMV 在合成聚合物降解中的作用。
