In this study, the bacterium XZ-A was genetically modified using atmospheric and room temperature plasma mutagenesis (ARTP) to increase the degradation efficiency of polyethylene microplastics (PE-MPs) by up to 53.65 %. After 50 d of biodegradation, the mutagenized bacterium XZ-60S caused significant changes in the morphology, structure, thermal stability, and molecular weight of PE-MPs. The number average molecular weights and weight average molecular weights of the PE-MPs were significantly reduced by approximately 15.21 % and 4.80 %, respectively. Comparative genomic and transcriptomic analyses showed that XZ-60S had a total of 106 single nucleotide polymorphic sites, and the expression of genes encoding laccases was significantly increased; this may explain the improved degradation of PE-MPs by XZ-60S. In this study, the degradation of PE-MPs by bacteria was improved through ARTP mutagenesis, which provides a reference for selecting and breeding bacteria that are highly efficient at degrading PE-MPs.

中文翻译：

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使用常压和室温等离子体诱变提高聚乙烯微塑料的细菌降解效率


在这项研究中，使用常压和室温等离子体诱变 （ARTP） 对细菌 XZ-A 进行基因改造，将聚乙烯微塑料 （PE-MP） 的降解效率提高高达 53.65 %。经过 50 d 的生物降解后，诱变细菌 XZ-60S 导致 PE-MPs 的形态、结构、热稳定性和分子量发生显著变化。PE-MPs 的数均分子量和重均分子量分别显著降低了约 15.21 % 和 4.80 %。比较基因组和转录组学分析显示，XZ-60S 共有 106 个单核苷酸多态性位点，编码漆酶的基因表达显著增加;这可能解释了 XZ-60S 对 PE-MPs 降解的改善。本研究通过 ARTP 诱变改善了细菌对 PE-MPs 的降解，为选择和培育高效降解 PE-MPs 的细菌提供了参考。