巢湖微囊藻产毒株的分离、保存及种属特异性鉴定

Isolation, Preservation, and Species Identification of a Toxigenic Strain of Microcystis from Chaohu Lake

摘要:

利用平板划线结合液体培养的方法从巢湖分离得到一个藻株, 命名为Chaohu-1。甲醇粗提该藻株所产生的藻毒素(MCs), 经固相萃取、HPLC检测, 证实该藻株产生毒性最强的Microcystin-LR。藻细胞呈绿色球状, 群体为无规则网状。全细胞PCR扩增藻蓝蛋白基因间隔序列(PC-IGS), 结果与GenBank中已有的铜绿微囊藻属序列相似性达99%。综合形态学和分子生物学的分析结果, 表明我们首次从巢湖分离得到1个产毒的铜绿微囊藻藻株。同时我们摸索出该藻株冻存及复苏方法, 为藻株的长期保存及后续研究打下了基础。

Abstract:

We isolated and purified a Microcystis strain, Chaohu-1, from Chaohu Lake by the method of plate streaking and liquid culture. After the successive steps of methanol extraction and solid-phase ex-traction, it was confirmed that the algae strain produces MC-LR as analyzed by HPLC. The algae cells were green and spherical, while the population displayed a random reticulate form. The phycocyanin intergenic spacer region (PC-IGS) was amplified by whole-cell PCR, cloned and sequenced. The PC-IGS sequence showed a degree of similarity of 99% with those of Microcystic aeruginosa strains downloaded from GenBank. A combination of the analysis results both at morphological and molecular levels indicated that for the first time we have isolated a Microcystis aeruginosa strain in Chaohu Lake, and we named it Chaohu-1. Moreover, we established an effective method for its cryopreservation and cell resuscitation, which laid foundation for the long-term preservation and the future research.