Department of Biology, College of Natural Sciences, Can Tho University, Vietnam; Lab. Aquatic Biology, Department of Biology, Campus Kulak Kortrijk, KU Leuven University, Etienne Sabbelaan 54, 8500 Kortrijk, Belgium.
Molecular Biotechnology Department, Biotechnology Research and Development Institute, Can Tho Universtiy, Vietnam.
Eur J Protistol. 2020 Oct;76:125743. doi: 10.1016/j.ejop.2020.125743. Epub 2020 Oct 14.
Ciliates are a common but understudied group of grazers that can invade microalgal cultures. To estimate the potential impact of ciliates on microalgal culture productivity, the identification of species that can invade these cultures is essential. Furthermore, isolation of these herbivorous ciliates allows to use them in experiments that investigate the impact of ciliate grazing on the productivity of microalgal cultures. The main aims of this study were to isolate and identify ciliates that invade cultures of the freshwater microalgae Chlorella and Chlamydomonas, and to establish a live collection of these ciliates for usage in future experiments. To this end, we optimized a method for isolating ciliates from contaminated microalgal cultures and we developed a new PCR primer set for amplifying the partial 18S rDNA of ciliates belonging to the classes Spirotrichea, Oligohymenophorea and Colpodea. As a result, we isolated 11 ciliates from microalgal enrichment cultures inoculated with non-sterile dust and various freshwater sources. Of these 11 species, 7 were found to be feeding on Chlamydomonas. Ciliate species that fed on Chlorella could not be isolated in this study. Ciliate species feeding on Chlamydomonas were identified based on a combination of morphological observations and molecular analyses of partial 18S rDNA sequences.
纤毛虫是一类常见但研究不足的食草动物，它们可以入侵微藻培养物。为了估计纤毛虫对微藻培养物生产力的潜在影响，识别可以入侵这些培养物的物种是至关重要的。此外，分离这些草食性纤毛虫可以用于实验，研究纤毛虫摄食对微藻培养物生产力的影响。本研究的主要目的是从淡水微藻小球藻和衣藻的污染培养物中分离和鉴定入侵的纤毛虫，并建立这些纤毛虫的活体收集，以供未来实验使用。为此，我们优化了一种从污染的微藻培养物中分离纤毛虫的方法，并开发了一种新的 PCR 引物对，用于扩增属于旋毛纲、寡膜纤毛虫纲和吸管纲的纤毛虫的部分 18S rDNA。结果，我们从用非无菌灰尘和各种淡水来源接种的微藻富集培养物中分离出 11 种纤毛虫。在这 11 个物种中，有 7 个被发现以衣藻为食。在本研究中，无法分离出以小球藻为食的纤毛虫。以衣藻为食的纤毛虫种是基于形态观察和部分 18S rDNA 序列的分子分析来鉴定的。
