纯培养节旋藻全基因组提取方法的比较研究

摘要

Single filaments of Arthrospira/Spirulina strains were picked up and axenicly cultured. Six protocols for ex-traction of whole genome DNA of the Arthrospira strains were comparatively studied. The phylogenetic analysis of 16S rRNA-ITS (internally transcribed spacer) gene sequences as molecular markers were conducted. The results show that the method of Freezing-thawing CTAB was effective in extracting extra-genomic DNA, not chromasomal from the tested strains. The extracted DNA containing excellent overall quality and high molecular weight can be directly used for molecular biology experiments. The molecular phylogenetic dendrogram indicates that the strains used in this research were all Arthrospira platensis, which were significantly different from strains of Spirulina in molecu-lar classification and identification in cyanobacterial genus.%本研究从实验室保藏的节旋藻(Arthrospira)藻种出发，挑取形态不同的单藻丝体进行纯化培养，采用6种方法进行全基因组DNA提取的比较研究，而后以16S rRNA-ITS区基因作为分子标记对藻株进行相关序列测定和分子系统进化分析。结果表明，冻融 CTAB 法能够提取出包含染色体外 DNA 在内的节旋藻全基因组，高质量样品可以满足分子生物学实验要求；分子系统研究表明，纯化藻株皆为钝顶节旋藻，节旋藻与螺旋藻在分子鉴定中属间差异明显。