†Department of Civil and Environmental Engineering, ‡Department of Microbiology and College of Medicine, and §Safe Global Water Institute, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, United States.
Environ Sci Technol. 2015 Apr 7;49(7):4584-90. doi: 10.1021/acs.est.5b00301. Epub 2015 Mar 19.
Free chlorine is effective at inactivating a wide range of waterborne viral pathogens including human adenovirus (HAdV), but the mechanisms by which free chlorine inactivates HAdV and other human viruses remain to be elucidated. Such advances in fundamental knowledge are key for development of new disinfection technologies and novel sensors to detect infectious viruses in drinking water. We developed and tested a quantitative assay to analyze several steps in the HAdV replication cycle upon increasing free chlorine exposure. We used quantitative polymerase chain reaction (qPCR) to detect HAdV genomic DNA as a means to quantify attachment and genome replication of untreated and treated virions. Also, we used quantitative reverse-transcription PCR (RT-qPCR) to quantify the transcription of E1A (first early protein) and hexon mRNA. We compared these replication cycle events to virus inactivation kinetics to determine what stage of the virus replication cycle was inhibited as a function of free chlorine exposure. We observed that adenovirus inactivated at levels up to 99.99% by free chlorine still attached to host cells; however, viral DNA synthesis and early E1A and late hexon gene transcription were inhibited. We conclude that free chlorine exposure interferes with a replication cycle event occurring postbinding but prior to early viral protein synthesis.
游离氯能有效灭活多种水源性病毒病原体，包括人类腺病毒（HAdV），但游离氯灭活 HAdV 和其他人类病毒的机制仍有待阐明。这些基础研究方面的进展对于开发新的消毒技术和新型传感器以检测饮用水中的传染性病毒至关重要。我们开发并测试了一种定量测定方法，以分析在增加游离氯暴露时 HAdV 复制周期的几个步骤。我们使用定量聚合酶链反应（qPCR）检测 HAdV 基因组 DNA，以定量分析未经处理和处理的病毒粒子的附着和基因组复制。此外，我们使用定量逆转录聚合酶链反应（RT-qPCR）定量检测 E1A（早期蛋白 1）和六邻体 mRNA 的转录。我们将这些复制周期事件与病毒失活动力学进行比较，以确定游离氯暴露作为功能抑制病毒复制周期的哪个阶段。我们观察到，游离氯能将腺病毒灭活至 99.99%，但仍附着在宿主细胞上；然而，病毒 DNA 合成以及早期 E1A 和晚期六邻体基因转录被抑制。我们得出结论，游离氯暴露干扰了结合后但在早期病毒蛋白合成之前发生的复制周期事件。
