Abstract：
Microbial colonization on plastic polymers has been extensively explored, however the temporal dynamics of biofilm community in Antarctic environments are almost unknown. As a contribute to fill this knowledge gap, the structural characteristics and microbial diversity of the biofilm associated with polyvinyl chloride (PVC) and polyethylene (PE) panels submerged at 5 m of depth and collected after 3, 9 and 12 months were investigated in four coastal sites of the Ross Sea. Additional panels placed at 5 and 20 m were retrieved after 12 months. Chemical characterization was performed by FTIR-ATR and Raman (through Surface-Enhanced Raman Scattering, SERS) spectroscopy. Bacterial community composition was quantified at a single cell level by Catalyzed Reporter Deposition Fluorescence In Situ Hybridization (CARD-FISH) and Confocal Laser Scanning Microscopy (CLSM); microbial diversity was assessed by 16S rRNA gene sequencing. This multidisciplinary approach has provided new insights into microbial community dynamics during biofouling process, shedding light on the biofilm diversity and temporal succession on plastic substrates in the Ross Sea. Significant differences between free-living and microbial biofilm communities were found, with a more consolidated and structured community composition on PVC compared to PE. Spectral features ascribable to tyrosine, polysaccharides, nucleic acids and lipids characterized the PVC-associated biofilms. Pseudomonadota (among Gamma-proteobacteria) and Alpha-proteobacteria dominated the microbial biofilm community. Interestingly, in Road Bay, close to the Italian \"Mario Zucchelli\" research station, the biofilm growth - already observed during summer season, after 3 months of submersion - continued afterwards leading to a massive microbial abundance at the end of winter (after 12 months). After 3 months, higher percentages of Gamma-proteobacteria in Road Bay than in the not-impacted site were found. These observations lead us to hypothesize that in this site microbial fouling developed during the first 3 months could serve as a starter pioneering community stimulating the successive growth during winter.
摘要：
微生物在塑料聚合物上的定植已经得到了广泛的探索，然而，南极环境中生物膜群落的时间动态几乎是未知的。作为填补这一知识空白的贡献，在罗斯海的四个沿海地点调查了与聚氯乙烯（PVC）和聚乙烯（PE）板淹没在5m深度并在3、9和12个月后收集的生物膜的结构特征和微生物多样性。12个月后取回放置在5和20m处的其他面板。通过FTIR-ATR和拉曼（通过表面增强拉曼散射，SERS)光谱学。通过催化报告物沉积荧光原位杂交（CARD-FISH）和共聚焦激光扫描显微镜（CLSM）在单细胞水平定量细菌群落组成；通过16SrRNA基因测序评估微生物多样性。这种多学科方法为生物污染过程中的微生物群落动态提供了新的见解，在罗斯海的塑料基质上释放生物膜多样性和时间演替的光。发现自由生活和微生物生物膜群落之间存在显着差异，与PE相比，PVC的社区组成更加巩固和结构化。酪氨酸的光谱特征，多糖，核酸和脂质表征了PVC相关的生物膜。假单胞菌（在γ变形杆菌中）和α变形杆菌在微生物生物膜群落中占主导地位。有趣的是,在路湾，靠近意大利“马里奥·祖切利”研究站，生物膜生长-已经在夏季观察到，经过3个月的浸没-之后继续导致大量的微生物丰度在冬季结束（12个月后）。三个月后,在RoadBay发现的Gammaproteobacteria百分比高于未受影响的站点。这些观察结果使我们假设，在该地点，前3个月中产生的微生物污垢可以作为启动先驱社区，刺激冬季的连续生长。
