This study investigated how a chloramine loss and nitrifying conditions influenced putative pathogenic bacterial diversity in bulk water and biofilm of a laboratory- and a full-scale chloraminated water distribution systems. Fifty-four reference databases containing full-length 16S rRNA gene sequences obtained from the National Centre for Biotechnology Information database were prepared to represent fifty-four pathogenic bacterial species listed in the World Health Organisation and Australian Drinking Water Quality Guidelines. When 16S rRNA gene sequences of all samples were screened against the fifty-four reference pathogenic databases, a total of thirty-one putative pathogenic bacteria were detected in both laboratory- and full-scale systems where total chlorine residuals ranged between 0.03 - 2.2 mg/L. Pathogenic bacterial species Mycolicibacterium fortuitum and Pseudomonas aeruginosa were noted in all laboratory (i.e. in bulk water and biofilm) and in bulk water of full-scale samples and Mycolicibacterium fortuitum dominated when chloramine residuals were high. Other different pathogenic bacterial species were observed dominant with decaying chloramine residuals. This study for the first time reports the diverse abundance of putative pathogenic bacteria resilient towards chloramine and highlights that metagenomics surveillance of drinking water can serve as a rapid assessment and an early warning of outbreaks of a large number of putative pathogenic bacteria.

这项研究调查了氯胺的损失和硝化条件如何影响实验室和大规模氯化水分配系统的散装水和生物膜中假定的致病细菌多样性。从国家生物技术信息中心的数据库中获得了包含全长16S rRNA基因序列的54个参考数据库，以代表世界卫生组织和澳大利亚饮用水水质准则中列出的54种致病细菌。当对照54个参考病原数据库筛选所有样品的16S rRNA基因序列时，在实验室和大型系统中总共检测到31个推定的病原细菌，其中总氯残留量在0.03-2.2 mg / L. 病原菌种在所有实验室中（即在散装水和生物膜中）以及在满刻度样品的散装水中，都注意到了福特分枝杆菌和铜绿假单胞菌，当氯胺残留较高时，福特分枝杆菌占主导。观察到其他不同的病原细菌种类占主导，并带有逐渐减少的氯胺残留。这项研究首次报道了对氯胺具有复原力的推定病原菌的多样性，并着重指出饮用水的宏基因组学监测可以作为对大量推定病原菌暴发的快速评估和预警。