Villegas Vanderville, Rajarajan Amruta, Funke Elisabeth, Mbedi Susan, Sparmann Sarah, Perez Jeffrey Paulo H, Schupp Benjamin, Wolinska Justyna
Leibniz Institute of Freshwater Ecology and Inland Fisheries (IGB), Berlin, Germany; Institute of Biology, Freie Universität Berlin, Germany.
Leibniz Institute of Freshwater Ecology and Inland Fisheries (IGB), Berlin, Germany.
Environ Pollut. 2025 Oct 1;382:126698. doi: 10.1016/j.envpol.2025.126698. Epub 2025 Jun 18.
Nanoplastics (NPs) are emerging contaminants of concern that may interact with natural biotic stressors (such as parasites) to disrupt host-associated microbiomes, which play a crucial role in the health and ecological dynamics of aquatic animals. Here, we investigate the effects of polystyrene NP beads and parasite infection on the microbiome diversity and composition of the model plankton organism Daphnia magna. We exposed D. magna to two NP sizes (50 nm and 100 nm) at two concentrations (1 mg L and 5 mg L), both with and without infection by the yeast parasite Metschnikowia bicuspidata and sequenced the microbiomes of gut and body tissues using 16S rRNA gene sequencing. High concentrations of 50 nm NPs significantly increased bacterial richness in both gut and body tissue, with shifts exceeding those induced by parasite infection. In the gut, the relative abundances of Burkholderiales and Chitinophagales decreased, while Caulobacterales, Rhizobiales, and Salinisphaerales increased. In body tissues, Chitinophagales declined, whereas Burkholderiales, Caulobacterales, Rhizobiales, and Salinisphaerales were enriched. NP size, concentration and interaction with infection, significantly influenced gut and body microbiome alpha diversity. Bray-Curtis dissimilarity analysis confirmed that 50 nm NPs drove distinct shifts in bacterial community composition, independent of parasite infection. Overall, NP-size and concentration had a stronger influence on the Daphnia microbiome than parasite infection. Given the critical roles of the Daphnia microbiome in nutritional support and stress tolerance, our findings highlight the potential ecological impacts of NPs on aquatic ecosystems.
纳米塑料（NPs）是新出现的受关注污染物，可能与天然生物应激源（如寄生虫）相互作用，破坏与宿主相关的微生物群，而这些微生物群在水生动物的健康和生态动态中起着关键作用。在此，我们研究了聚苯乙烯NP珠和寄生虫感染对模式浮游生物大型溞微生物群多样性和组成的影响。我们将大型溞暴露于两种NP尺寸（50纳米和100纳米）和两种浓度（1毫克/升和5毫克/升）下，有无酵母寄生虫双尖梅奇酵母感染，并使用16S rRNA基因测序对肠道和身体组织的微生物群进行测序。高浓度的50纳米NP显著增加了肠道和身体组织中的细菌丰富度，其变化超过了寄生虫感染引起的变化。在肠道中，伯克霍尔德菌目和噬几丁质菌目的相对丰度下降，而柄杆菌目、根瘤菌目和盐球菌目增加。在身体组织中，噬几丁质菌目减少，而伯克霍尔德菌目、柄杆菌目、根瘤菌目和盐球菌目富集。NP尺寸、浓度以及与感染的相互作用，显著影响肠道和身体微生物群的α多样性。Bray-Curtis差异分析证实，50纳米NP导致细菌群落组成发生明显变化，与寄生虫感染无关。总体而言，NP尺寸和浓度对大型溞微生物群的影响比寄生虫感染更强。鉴于大型溞微生物群在营养支持和应激耐受性方面的关键作用，我们的研究结果突出了NP对水生生态系统的潜在生态影响。
