HGM2003 Poster Abstracts
5. Bioinformatics DNA Sequencing and Analysis

Poster 149

Trinucleotide statistics classify viruses and bacteriophages of different nucleotide types

¹Fumihiko Takeuchi, ¹Yasuhiro Futamura, ²Hiroshi Yoshikura, ¹Kenji Yamamoto
¹Research Institute, International Medical Center of Japan, 162-8655, Japan, ²National Institute of Infectious Diseases, 162-8640, Japan

We previously reported measurements indicative of evolutional stages of species. They were statistics of trinucleotides in coding regions. Among them was the codon space, the nucleotide ratio for each of the three codon positions. We applied principal component analysis on this space and extracted two principal components faithfully describing the original distribution of the codon space. The first principal component corresponded to the GC content. The second principal component classified the species into three evolutional groups, Archaea, Bacteria and Eukaryota.

We now apply this analysis to viruses, which infect to Eukaryota, and bacteriophages, which infect to Bacteria. We show that 1) the principal components of the codon space of viruses are similar to that of their host, but that 2) the second principal component split DNA and RNA viruses with DNA viruses being more like Eukaryota and RNA viruses more like Bacteria.