巨大ウイルスの進化過程に関する研究

概要

令和 4 年度

京都大学化学研究所 スーパーコンピュータシステム 利用報告書
巨大ウイルスの進化過程に関する研究
Analysis of the evolution of giant viruses

京都大学 化学研究所 バイオインフォマティクスセンター 化学生命科学領域

張 利雯

研究成果概要
To understand the whole picture of evolution history of giant viruses, this study investigated
their on-going evolution first. This study starts with investigating the true diversity of giant
viruses in a freshwater lake. I used the metagenomic data from Biwa Lake. Spatiotemporal
sampling from two water layers enabled us to investigate their different adaptive strategies in
hypolimnion and epilimnion respectively.
I mainly used tools related to contig assembly (SPAdes), genome binner(metabat2), and viral
annotation (CAT/VirSorter/ViralRecall). As a result, I got hundreds of metagenomes assembled
NCLDV genomes for downstream analysis. Then I analyzed the community genome dynamics
across the whole sampling year and found NCLDVs are showing different consistency in two
water layers. I also used mapping tools to evaluate the coverage of contigs and MAGs
(BWA/minimap2/samtools/CoverM/Bowtie2).

I

removed

low-coverage

MAGs

from

downstream analysis.
For further analysis, I would analyze the tandem repeats found in NCLDV MAGs are
family-specific or prevalent in all NCLDV genomes. ...