Abstract：
Although simulated studies have provided valuable knowledge regarding the communities of planktonic bacteria and biofilms, the lack of systematic field studies have hampered the understanding of microbiology in real-world service lines and premise plumbing. In this study, the bacterial communities of water and biofilm were explored, with a special focus on the lifetime development of biofilm communities and their key influencing factors. The 16S rRNA gene sequencing results showed that both the planktonic bacteria and biofilm were dominated by Proteobacteria. Among the 15,084 observed amplicon sequence variants (ASVs), the 33 core ASVs covered 72.8 %, while the 12 shared core ASVs accounted for 62.2 % of the total sequences. Remarkably, it was found that the species richness and diversity of biofilm communities correlated with pipe age. The relative abundance of ASV2 (f_Sphingomonadaceae) was lower for pipe ages 40-50 years (7.9 %) than for pipe ages 10-20 years (59.3 %), while the relative abundance of ASV10 (f_Hyphomonadaceae) was higher for pipe ages 40-50 years (19.5 %) than its presence at pipe ages 20-30 years (1.9 %). The community of the premise plumbing biofilm had significantly higher species richness and diversity than that of the service line, while the steel-plastics composite pipe interior lined with polyethylene (S-PE) harbored significantly more diverse biofilm than the galvanized steel pipes (S-Zn). Interestingly, S-PE was enriched with ASV27 (g_Mycobacterium), while S-Zn pipes were enriched with ASV13 (g_Pseudomonas). Moreover, the network analysis showed that five rare ASVs, not core ASVs, were keystone members in biofilm communities, indicating the importance of rare members in the function and stability of biofilm communities. This manuscript provides novel insights into real-world service lines and premise plumbing microbiology, regarding lifetime dynamics (pipe age 10-50 years), and the influences of pipe types (premise plumbing vs. service line) and pipe materials (S-Zn vs. S-PE).
摘要：
尽管模拟研究提供了有关浮游细菌和生物膜群落的宝贵知识，缺乏系统的实地研究阻碍了对现实世界服务线路和前提管道中微生物学的理解。在这项研究中,探索了水和生物膜的细菌群落，特别关注生物膜群落的终生发育及其关键影响因素。16SrRNA基因测序结果表明，浮游细菌和生物膜均以变形杆菌为主。在15,084个观察到的扩增子序列变体（ASV）中，33个核心ASV占72.8%，而12个共享核心ASV占总序列的62.2%。值得注意的是,发现生物膜群落的物种丰富度和多样性与管龄相关。ASV2（f_Sphingomonadaceae）的相对丰度在40-50岁的管道年龄（7.9％）低于10-20岁的管道年龄（59.3％），而ASV10（f_Hyphomonadaceae）的相对丰度在40-50岁的管道年龄（19.5％）高于其在20-30岁的管道年龄（1.9％）的存在。前提管道生物膜的群落具有明显高于服务线的物种丰富度和多样性，与镀锌钢管（S-Zn）相比，内衬聚乙烯（S-PE）的钢塑复合管具有更多样化的生物膜。有趣的是,S-PE富集ASV27(g_Mycobacterium),而S-Zn管道富含ASV13(g_Pseudomonas)。此外，网络分析显示，五种罕见的ASV，不是核心ASV，是生物膜社区的基石成员，表明稀有成员在生物膜群落功能和稳定性中的重要性。这份手稿提供了对现实世界服务线和前提管道微生物学的新颖见解，关于寿命动态(管龄10-50年)，以及管道类型的影响(前提管道与服务线)和管道材料(S-Zn与S-PE）。
