Faculty of Science, Health and Education, University of the Sunshine Coast, Maroochydore DC 4558, Queensland, Australia; Smart Water Research Centre, Griffith University, Gold Coast Campus, Queensland, Australia.
Water Res. 2013 Nov 1;47(17):6670-9. doi: 10.1016/j.watres.2013.09.008. Epub 2013 Sep 13.
We investigated the survival of Escherichia coli in two STPs utilising UV irradiation (STP-A) or chlorination (STP-B) for disinfection. In all, 370 E. coli strains isolated from raw influent sewage (IS), secondary treated effluent (STE) and effluent after the disinfection processes of both STPs were typed using a high resolution biochemical fingerprinting method and were grouped into common (C-) and single (S-) biochemical phenotypes (BPTs). In STP-A, 83 BPTs comprising 123 isolates were found in IS and STE, of which 7 BPTs survived UV irradiation. Isolates tested from the same sites of STP-B (n = 220) comprised 122 BPTs, however, only two BPTs were found post-chlorination. A representative isolate from each BPT from both STPs was tested for the presence of 11 virulence genes (VGs) associated with uropathogenic (UPEC) or intestinal pathogenic (IPEC) E. coli strains. Strains surviving UV irradiation were distributed among seven phylogenetic groups with five BPTs carrying VGs associated with either UPEC (4 BPTs) or IPEC (1 BPT). In contrast, E. coli strains found in STP-B carried no VGs. Strains from both STPs were resistant to up to 12 out of the 21 antibiotics tested but there was no significant difference between the numbers of antibiotics to which surviving strains were resistant to in these STPs. Our data suggests that some E. coli strains have a better ability to survive STPs utilising chlorination and UV irradiation for disinfection. However, strains that survive UV irradiation are more diverse and may carry more VGs than those surviving SPTs using chlorination.
我们研究了两种使用紫外线（STP-A）或氯化（STP-B）进行消毒的污水处理厂中大肠杆菌的生存情况。总共从原污水进水（IS）、二级处理出水（STE）和两个 STP 消毒过程后的出水分离出 370 株大肠杆菌菌株，使用高分辨率生化指纹图谱方法对这些菌株进行了分型，并将其分为常见（C-）和单一（S-）生化表型（BPT）。在 STP-A 中，IS 和 STE 中发现了包含 123 株分离株的 83 个 BPT，其中 7 个 BPT 可耐受紫外线照射。从 STP-B 相同地点测试的分离株（n=220）包含 122 个 BPT，但只有两个 BPT 在氯化后存在。从两个 STP 的每个 BPT 中选择一个代表性分离株，检测与尿路致病性（UPEC）或肠致病性（IPEC）大肠杆菌菌株相关的 11 个毒力基因（VG）。可耐受紫外线照射的菌株分布在七个进化群中，其中五个 BPT 携带与 UPEC（4 个 BPT）或 IPEC（1 个 BPT）相关的 VG。相比之下，在 STP-B 中发现的大肠杆菌菌株不携带 VG。两个 STP 的分离株对测试的 21 种抗生素中的多达 12 种具有耐药性，但在这些 STP 中，存活菌株对不同抗生素的耐药性数量没有显著差异。我们的数据表明，一些大肠杆菌菌株在使用氯化和紫外线进行消毒的污水处理厂中有更好的生存能力。然而，与使用氯化消毒的 STP 相比，可耐受紫外线照射的菌株具有更高的多样性，并且可能携带更多的 VG。
