Cheng Jingguang, Jacquin Justine, Conan Pascal, Pujo-Pay Mireille, Barbe Valérie, George Matthieu, Fabre Pascale, Bruzaud Stéphane, Ter Halle Alexandra, Meistertzheim Anne-Leila, Ghiglione Jean-François
UMR 7621, CNRS, Laboratoire d'Océanographie Microbienne, Observatoire Océanologique de Banyuls-sur-Mer, Sorbonne Université, Banyuls-sur-Mer, France.
Génomique Métabolique, Genoscope, Institut François Jacob, CEA, CNRS, Univ Evry, Université Paris-Saclay, Evry, France.
Front Microbiol. 2021 Jan 13;11:610231. doi: 10.3389/fmicb.2020.610231. eCollection 2020.
The thin film of life that inhabits all plastics in the oceans, so-called "plastisphere," has multiple effects on the fate and impacts of plastic in the marine environment. Here, we aimed to evaluate the relative influence of the plastic size, shape, chemical composition, and environmental changes such as a phytoplankton bloom in shaping the plastisphere abundance, diversity and activity. Polyethylene (PE) and polylactide acid (PLA) together with glass controls in the forms of meso-debris (18 mm diameter) and large-microplastics (LMP; 3 mm diameter), as well as small-microplastics (SMP) of 100 μm diameter with spherical or irregular shapes were immerged in seawater during 2 months. Results of bacterial abundance (confocal microscopy) and diversity (16S rRNA Illumina sequencing) indicated that the three classical biofilm colonization phases (primo-colonization after 3 days; growing phase after 10 days; maturation phase after 30 days) were not influenced by the size and the shape of the materials, even when a diatom bloom ( sp.) occurred after the first month of incubation. However, plastic size and shape had an effect on bacterial activity (H leucine incorporation). Bacterial communities associated with the material of 100 μm size fraction showed the highest activity compared to all other material sizes. A mature biofilm developed within 30 days on all material types, with higher bacterial abundance on the plastics compared to glass, and distinct bacterial assemblages were detected on each material type. The diatom bloom event had a great impact on the plastisphere of all materials, resulting in a drastic change in diversity and activity. Our results showed that the plastic size and shape had relatively low influence on the plastisphere abundance, diversity, and activity, as compared to the plastic composition or the presence of a phytoplankton bloom.
生活在海洋中所有塑料上的薄薄一层生物，即所谓的“塑料球”，对塑料在海洋环境中的归宿和影响具有多种作用。在此，我们旨在评估塑料的尺寸、形状、化学成分以及诸如浮游植物大量繁殖等环境变化对塑料球的丰度、多样性和活性形成的相对影响。将聚乙烯（PE）和聚乳酸（PLA）以及玻璃对照物制成中碎屑（直径18毫米）、大型微塑料（LMP；直径3毫米）的形式，还有直径100微米的球形或不规则形状的小型微塑料（SMP），在海水中浸泡2个月。细菌丰度（共聚焦显微镜）和多样性（16S rRNA Illumina测序）结果表明，三个经典的生物膜定殖阶段（3天后的初次定殖；10天后的生长阶段；30天后的成熟阶段）不受材料尺寸和形状的影响，即使在培养第一个月后出现了硅藻大量繁殖（ 种）。然而，塑料尺寸和形状对细菌活性（亮氨酸掺入）有影响。与100微米尺寸级别的材料相关的细菌群落相比所有其他材料尺寸显示出最高的活性。在所有材料类型上30天内都形成了成熟的生物膜，塑料上的细菌丰度高于玻璃，并且在每种材料类型上检测到不同的细菌组合。硅藻大量繁殖事件对所有材料的塑料球都有很大影响，导致多样性和活性发生急剧变化。我们的结果表明，与塑料成分或浮游植物大量繁殖的存在相比，塑料尺寸和形状对塑料球的丰度、多样性和活性的影响相对较小。
