Preparation method of environmental DNA sample for conservation of the genetic resource in the deep subsurface biosphere and analysis of biodiviersity harbored in the DNA

我们试图主要从在岛下半岛附近发现的大洋钻探岩心样本中提取环境DNA。提取的DNA随着深度的增加而减少，但从DNA数量估计的细胞数与显微镜下计数的细胞数相差不大。至此，DNA提取方法已基本建立。我们还分析了基于16S rDNA的生物多样性，并根据DNA样本中已识别的基因预测了代谢潜力。JS1和Chloroflei被发现是优势分类群，如前所述，深度可达100米。在每个不同深度的DNA样本中，鉴定出了6-8万个基因。硫磺呼吸相关基因和产甲烷相关基因分别在浅层和深层突出。

We attempted to extract environmental DNA mainly from ocean drilling core samples recovered offshore Shimokita Peninsula. The extracted DNA decreased with increasing of depth but the estimated cell number from DNA amount was not so different from those counted by microscopy. Thus, It is though that the DNA extraction method was almost successfully established. We also analyzed to figure out biodiversity based on 16S rDNA and the predicted metabolic potential from the identified genes in the DNA samples. JS1 and Chloroflexi were found to be predominant taxa as described previously up to a depth of 100m. In each DNA sample from different depth, 60,000-80,000 genes were identified. The sulfur respiration-related genes and methanogenesis-related genes were highlighted in sallower and deeper horizons, respectively.