Environmental pollution by plastic debris is estimated on a scale of 100 million metric tons, a portion of which is fragmented into micro- and nanoplastics. These fragments are often colonized by bacterial species in marine environments, possibly contributing to the biodegradation of such materials. However, further investigations are necessary to determine the impact of abiotic polymer weathering on biofilm adhesion, as well as the specific biofilm formation strategies employed by marine isolates. Here, we evaluate deep-sea sediment bacterial isolates for biofilm adhesion, extracellular matrix production, and polymer degradation ability. Our study focuses on high-density polyethylene (HDPE) fragments for their high durability and environmental persistence, subjecting fragments to abiotic weathering prior to bacterial colonization. Marine isolates identified as Pseudomonas sp. and Lysinibacillus sp. exhibited decreasing biofilm formation on weathered HDPE, especially over the first 24 h of incubation. This effect was countered by increased extracellular matrix production, likely improving cell adhesion to surfaces roughened by abiotic degradation. These adhesion strategies were contrasted with a reference Pseudomonas aeruginosa strain, which displayed high levels of biofilm formation on non-weathered HDPE and lower extracellular matrix production over the first 24 h of incubation. Furthermore, our results suggest that an increase in biofilm biomass correlated with changes to HDPE structure, indicating that these strains have a potential for biodegradation of plastic fragments. Therefore, this work provides a detailed account of biofilm formation strategies and bacteria-plastic interactions that represent crucial steps in the biodegradation of plastic fragments in marine environments.

塑料碎片造成的环境污染估计达 1 亿公吨，其中一部分被分解成微塑料和纳米塑料。这些碎片通常被海洋环境中的细菌物种定殖，可能有助于这些材料的生物降解。然而，需要进一步研究以确定非生物聚合物风化对生物膜粘附的影响，以及海洋分离物采用的特定生物膜形成策略。在这里，我们评估了深海沉积物细菌分离物的生物膜粘附、细胞外基质产生和聚合物降解能力。我们的研究侧重于高密度聚乙烯 (HDPE) 碎片，因为它们具有高耐久性和环境持久性，在细菌定植之前使碎片经受非生物风化。假单胞菌属 和赖氨酸杆菌属。在风化的 HDPE 上表现出减少的生物膜形成，尤其是在孵化的前 24 小时内。这种效应被增加的细胞外基质产生所抵消，这可能会改善细胞对因非生物降解而变得粗糙的表面的粘附。这些粘附策略与参考铜绿假单胞菌形成对比菌株，其在未风化的 HDPE 上显示出高水平的生物膜形成，并且在孵育的前 24 小时内显示出较低的细胞外基质产量。此外，我们的结果表明，生物膜生物量的增加与 HDPE 结构的变化相关，表明这些菌株具有生物降解塑料碎片的潜力。因此，这项工作详细说明了生物膜形成策略和细菌-塑料相互作用，它们代表了海洋环境中塑料碎片生物降解的关键步骤。