Stewart-Pullaro J, Daugomah J W, Chestnut D E, Graves D A, Sobsey M D, Scott G I
NOAA, Center for Coastal Environmental Health and Biomolecular Research, Charleston, SC, USA.
J Appl Microbiol. 2006 Nov;101(5):1015-26. doi: 10.1111/j.1365-2672.2006.03011.x.
The utility of coliphages to detect and track faecal pollution was evaluated using South Carolina surface waters that exceeded State faecal coliform standards.
Coliphages were isolated from 117 surface water samples by single agar layer (SAL) and enrichment presence/absence (EP/A) methods. Confirmed F+ RNA coliphages were typed for microbial source tracking using a library-independent approach. Concentrations of somatic coliphages using 37 and 44.5 degrees C incubation temperatures were found to be significantly different and the higher temperature may be more specific for faecal contamination. The EP/A technique detected coliphages infecting Escherichia coli Famp in 38 (66%) of the 58 surface water samples negative for F+ coliphages by the SAL method. However, coliphages isolated by EP/A were found to be less representative of coliphage diversity within a sample. Among the 2939 coliphage isolates tested from surface water and known source samples, 813 (28%) were found to be F+ RNA. The majority (94%) of surface water F+ RNA coliphage isolates typed as group I. Group II and/or III viruses were identified from 14 surface water stations, the majority of which were downstream of wastewater discharges. These sites were likely contaminated by human-source faecal pollution.
The results suggest that faecal contamination in surface waters can be detected and source identifications aided by coliphage analyses.
This study supports the premise that coliphage typing can provide useful, but not absolute, information to distinguish human from animal sources of faecal pollution. Furthermore, the comparison of coliphage isolation methods detailed in this study should provide valuable information to those wishing to incorporate coliphage detection into water quality assessments.
利用南卡罗来纳州超过该州粪大肠菌群标准的地表水，评估大肠杆菌噬菌体检测和追踪粪便污染的效用。
通过单琼脂层（SAL）和富集存在/缺失（EP/A）方法，从117个地表水样本中分离出大肠杆菌噬菌体。使用一种不依赖文库的方法对已确认的F+RNA大肠杆菌噬菌体进行分型，以进行微生物源追踪。发现使用37℃和44.5℃培养温度时，体细胞大肠杆菌噬菌体的浓度存在显著差异，较高温度可能对粪便污染更具特异性。EP/A技术在SAL方法检测为F+噬菌体阴性的58个地表水样本中的38个（66%）中，检测到感染大肠杆菌Famp的噬菌体。然而，发现通过EP/A分离的噬菌体在样本中对噬菌体多样性的代表性较差。在从地表水和已知源样本中测试的2939个噬菌体分离物中，发现813个（28%）为F+RNA。地表水F+RNA噬菌体分离物的大多数（94%）被分型为I组。从14个地表水监测站鉴定出II组和/或III组病毒，其中大多数位于废水排放下游。这些地点可能受到人类源粪便污染。
结果表明，通过噬菌体分析可以检测地表水的粪便污染并有助于来源鉴定。
本研究支持这样一个前提，即噬菌体分型可以提供有用但非绝对的信息，以区分人类和动物源的粪便污染。此外，本研究中详细比较的噬菌体分离方法，应为那些希望将噬菌体检测纳入水质评估的人提供有价值的信息。
