Center for Research on Intracellular Bacteria, Institute of Microbiology, Faculty of Biology and Medecine, University of Lausanne, Bugnon 46, 1011 Lausanne, Switzerland.
Int J Hyg Environ Health. 2010 Jun;213(3):158-66. doi: 10.1016/j.ijheh.2010.03.002. Epub 2010 Apr 18.
In this study, we enlarged our previous investigation focusing on the biodiversity of chlamydiae and amoebae in a drinking water treatment plant, by the inclusion of two additional plants and by searching also for the presence of legionellae and mycobacteria. Autochthonous amoebae were recovered onto non-nutritive agar, identified by 18S rRNA gene sequencing, and screened for the presence of bacterial endosymbionts. Bacteria were also searched for by Acanthamoeba co-culture. From a total of 125 samples, we recovered 38 amoebae, among which six harboured endosymbionts (three chlamydiae and three legionellae). In addition, we recovered by amoebal co-culture 11 chlamydiae, 36 legionellae (no L. pneumophila), and 24 mycobacteria (all rapid-growers). Two plants presented a similar percentage of samples positive for chlamydiae (11%), mycobacteria (20%) and amoebae (27%), whereas in the third plant the number of recovered bacteria was almost twice higher. Each plant exhibited a relatively high specific microbiota. Amoebae were mainly represented by various Naegleria species, Acanthamoeba species and Hartmannella vermiformis. Parachlamydiaceae were the most abundant chlamydiae (8 strains in total), and in this study we recovered a new genus-level strain, along with new chlamydiae previously reported. Similarly, about 66% of the recovered legionellae and 47% of the isolated mycobacteria could represent new species. Our work highlighted a high species diversity among legionellae and mycobacteria, dominated by putative new species, and it confirmed the presence of chlamydiae in these artificial water systems.
在这项研究中，我们扩大了之前的研究范围，除了之前的研究对象外，还包括另外两个饮用水处理厂，同时也在研究中寻找军团菌和分枝杆菌的存在。通过非营养琼脂从原生动物中回收并通过 18S rRNA 基因测序鉴定，筛选细菌内共生体的存在。还通过棘阿米巴共培养来寻找细菌。从总共 125 个样本中，我们回收了 38 个变形虫，其中 6 个携带内共生体（3 种衣原体和 3 种军团菌）。此外，我们通过变形虫共培养还回收了 11 种衣原体、36 种军团菌（无嗜肺军团菌）和 24 种分枝杆菌（均为快速生长菌）。两个工厂的衣原体（11%）、分枝杆菌（20%）和变形虫（27%）阳性样本比例相似，而第三个工厂回收的细菌数量几乎是前两个工厂的两倍。每个工厂都表现出相对较高的特定微生物群。变形虫主要由各种纳氏虫、棘阿米巴虫和变形虫属组成。副衣原体科是最丰富的衣原体（共 8 株），在本研究中，我们还分离到了一个新的属级菌株，以及以前报道过的新衣原体。同样，大约 66%的回收军团菌和 47%的分离分枝杆菌可能代表新的物种。我们的工作突出了军团菌和分枝杆菌的高物种多样性，主要由可能的新物种组成，并证实了衣原体在这些人工水系统中的存在。
