van Overbeek Leo, Gassner Fedor, van der Plas Carin Lombaers, Kastelein Pieter, Nunes-da Rocha Ulisses, Takken Willem
Wageningen University and Research Centre, Plant Sciences Group, PB, Wageningen, The Netherlands.
FEMS Microbiol Ecol. 2008 Oct;66(1):72-84. doi: 10.1111/j.1574-6941.2008.00468.x.
Nymphal Ixodes ricinus ticks (n=180) were collected from three different areas in the Netherlands to investigate the effect of forest composition on tick-associated microbial communities. Sampled habitats differed in thickness of leaf litter and humus layers and vegetation associations and were located near Amsterdam (Beech-Oak), Ede (Birch-Oak) and Veldhoven (Birch-Oak). Analysis of nine 16S rRNA gene clone libraries made from individual ticks showed nearest matches with presumed pathogens Candidatus Neoehrlichia mikurensis and Rickettsia australis and arthropod endosymbionts Wolbachia pipientis and Candidatus Midichloria mitochondrii. Total bacterial species diversity (Shannon index) and Borrelia species infections were determined in I. ricinus by, respectively, PCR-denaturing gradient gel-electrophoresis and PCR-reverse line blot with probes specific for Borrelia burgdorferi sensu stricto, Borrelia afzelii, Borrelia garinii, Borrelia valaisiana, Borrelia lusitaniae and Borrelia ruski. Bacterial diversity differed significantly per area and was lowest in Ede. In contrast, Borrelia species-infected ticks were more abundant in Ede, Candidatus Neoehrlichia mikurensis-infected ticks in Ede and Veldhoven, and R. australis-infected ticks in Amsterdam. Borrelia afzelii was the most common Borrelia species found in all three areas. Bacterial tick diversity was influenced by local differences in forest structure, which is proposed to modulate animal populations that are commonly parasitized by I. ricinus.
从荷兰的三个不同地区采集了180只蓖麻硬蜱若虫，以研究森林组成对蜱相关微生物群落的影响。采样的栖息地在落叶层和腐殖质层的厚度以及植被关联方面存在差异，分别位于阿姆斯特丹附近（山毛榉 - 橡树）、埃因霍温（桦树 - 橡树）和费尔德霍芬（桦树 - 橡树）。对从单个蜱虫制备的9个16S rRNA基因克隆文库的分析表明，与假定病原体米氏新埃立克体和澳大利亚立克次体以及节肢动物内共生菌嗜菌沃尔巴克氏体和线粒体中假丝酵母最匹配。通过PCR - 变性梯度凝胶电泳和针对狭义伯氏疏螺旋体、阿氏疏螺旋体、伽氏疏螺旋体、瓦氏疏螺旋体、卢氏疏螺旋体和鲁斯疏螺旋体的特异性探针的PCR - 反向线杂交分别测定了蓖麻硬蜱中的总细菌物种多样性（香农指数）和伯氏疏螺旋体物种感染情况。各地区的细菌多样性差异显著，在埃因霍温最低。相比之下，感染伯氏疏螺旋体物种的蜱虫在埃因霍温更为丰富，感染米氏新埃立克体的蜱虫在埃因霍温和费尔德霍芬较多，而感染澳大利亚立克次体的蜱虫在阿姆斯特丹较多。阿氏疏螺旋体是在所有三个地区发现的最常见的伯氏疏螺旋体物种。蜱虫的细菌多样性受森林结构局部差异的影响，而森林结构被认为会调节通常被蓖麻硬蜱寄生的动物种群。
