Center for Biomedical Engineering, School of Engineering, Brown University, Providence, Rhode Island, United States of America.
University of Rhode Island, Kingston, Rhode Island, United States of America.
PLoS One. 2020 Jul 1;15(7):e0232745. doi: 10.1371/journal.pone.0232745. eCollection 2020.
Microplastics or plastic particles less than 5 mm in size are a ubiquitous and damaging pollutant in the marine environment. However, the interactions between these plastic particles and marine microorganisms are just starting to be understood. The objective of this study was to measure the responses of a characteristic marine organism (Synechococcus sp. PCC 7002) to an anthropogenic stressor (polyethelene nanoparticles and microparticles) using molecular techniques. This investigation showed that polyethylene microparticles and nanoparticles have genetic, enzymatic and morphological effects on Synechococcus sp. PCC 7002. An RT-PCR analysis showed increases in the expression of esterase and hydrolase genes at 5 days of exposure to polyethylene nanoparticles and at 10 days of exposure to polyethylene microparticles. A qualitative enzymatic assay also showed esterase activity in nanoparticle exposed samples. Cryo-scanning electron microscopy was used to assess morphological changes in exopolymer formation resulting from exposure to polyethylene microparticles and nanoparticles. The data from this paper suggests that microplastic and nanoplastics could be key microbial stressors and should be investigated in further detail.
微塑料或粒径小于 5 毫米的塑料颗粒是海洋环境中普遍存在且具有危害性的污染物。然而，这些塑料颗粒与海洋微生物之间的相互作用才刚刚开始被人们所理解。本研究旨在使用分子技术来测量一种典型的海洋生物（聚球藻 PCC 7002）对人为胁迫（聚乙烯纳米颗粒和微颗粒）的反应。这项研究表明，聚乙烯微颗粒和纳米颗粒对聚球藻 PCC 7002 具有遗传、酶和形态学效应。RT-PCR 分析显示，在暴露于聚乙烯纳米颗粒 5 天后和暴露于聚乙烯微颗粒 10 天后，酯酶和水解酶基因的表达增加。定性酶分析还显示纳米颗粒暴露样品中有酯酶活性。使用冷冻扫描电子显微镜评估了由于暴露于聚乙烯微颗粒和纳米颗粒而导致的胞外聚合物形成的形态变化。本文的数据表明，微塑料和纳米塑料可能是关键的微生物胁迫因素，应进一步详细研究。
