Abstract：
Plastic pollution in the marine realm is a severe environmental problem. Nevertheless, plastic may also serve as a potential carbon and energy source for microbes, yet the contribution of marine microbes, especially marine fungi to plastic degradation is not well constrained. We isolated the fungus Parengyodontium album from floating plastic debris in the North Pacific Subtropical Gyre and measured fungal-mediated mineralization rates (conversion to CO2) of polyethylene (PE) by applying stable isotope probing assays with 13C-PE over 9 days of incubation. When the PE was pretreated with UV light, the biodegradation rate of the initially added PE was 0.044 %/day. Furthermore, we traced the incorporation of PE-derived 13C carbon into P. album biomass using nanoSIMS and fatty acid analysis. Despite the high mineralization rate of the UV-treated 13C-PE, incorporation of PE-derived 13C into fungal cells was minor, and 13C incorporation was not detectable for the non-treated PE. Together, our results reveal the potential of P. album to degrade PE in the marine environment and to mineralize it to CO2. However, the initial photodegradation of PE is crucial for P. album to metabolize the PE-derived carbon.
摘要：
海洋领域的塑料污染是一个严重的环境问题。然而，塑料还可以作为微生物的潜在碳源和能源，然而海洋微生物的贡献，特别是海洋真菌对塑料的降解没有很好的约束。我们从北太平洋亚热带环流的漂浮塑料碎片中分离出真菌Parengyodontium专辑，并通过在9天的孵育中使用13C-PE进行稳定的同位素探测测定法，测量了聚乙烯（PE）的真菌介导的矿化率（转化为CO2）。当PE用UV光预处理时,最初添加的PE的生物降解率为0.044%/天。此外，我们使用nanoSIMS和脂肪酸分析追踪了PE衍生的13C-碳在P.baler生物质中的掺入。尽管紫外线处理的13C-PE的矿化率高，PE衍生的13C掺入真菌细胞是次要的，未处理的PE未检测到13C掺入。一起,我们的结果揭示了P.album在海洋环境中降解PE并将其矿化为CO2的潜力。然而,PE的初始光降解对于P.alum代谢PE衍生的碳至关重要。
