An evaluation of methods to study the gut bacterial community composition of freshwater zooplankton
An evaluation of methods to study the gut bacterial community composition of freshwater zooplankton
复制标题
淡水浮游动物肠道细菌群落组成研究方法评价
DOI：
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发表时间：
2008
期刊：
影响因子：
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通讯作者：
R. Sommaruga
中科院分区：
文献类型：
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作者：
H. Peter;R. Sommaruga
人们早就认识到淡水和海洋浮游动物中肠道细菌的存在，但关于肠道“微生物群”的组成及其在不同浮游动物中的永久存在的知识仍然不足。在这项研究中，我们测试了荧光原位杂交（FISH）、催化报告沉积(CARD)-FISH、培养和透射电子显微镜（TEM）在匀浆和整个标本切片上的适用性，以评估几种淡水桡足类和枝海类物种肠道细菌的存在和鉴定。通过透射电镜，获得了新捕获的水蚤永久肠道“微生物群”存在的明确结果。CARD-FISH对棘足突和棘足突的肠道匀浆进行了研究，发现细菌组成与水柱中的细菌组成非常相似。在支大洋动物和桡足动物中发现的主要细菌类群是α -、β -、γ -变形菌门和细胞噬黄菌门。α -变形菌门在齿角甲中的高贡献表明这一群体有一个特定的生态位，但可能与它的甲壳有关。石蜡半薄切片上的FISH有可能提供肠道“微生物群”组成的定量和定性信息，但细菌和肠道含量的损失是显著的。
The occurrence of gut bacteria in freshwater and marine zooplankton has long been recognized, but knowledge about the composition of the gut "microflora" and its permanent presence in different zooplankters is still inadequate. In this study, we tested the suitability of fluorescence in situ hybridization (FISH), catalysed reporter deposition (CARD)-FISH, cultivation and transmission electron microscopy (TEM) on homogenates and whole-specimen sections to assess the presence and identity of gut bacteria in several freshwater copepod and cladoceran species. Unambiguous results about the presence of a permanent gut "microflora" were obtained for freshly caught Daphnia pulex by TEM. CARD-FISH on gut homogenates from Acanthodiaptomus denticornis and D. pulex revealed a very similar bacterial composition to that present in the water column. Major bacterial groups found in cladocerans and copepods were alpha-, beta-, gamma-Proteobacteria and Cytophaga–Flavobacteria. The high contribution of alpha-Proteobacteria in A. denticornis suggested a specific niche for this group, but probably in association with its carapace. FISH on paraffin semithin sections had the potential to provide quantitative and qualitative information about the composition of the gut "microflora", but loss of bacteria and gut content was significant.