Average AT scores and OUV content in cluster groups. The graphs shows average AT content (left) and OUV scores (right) on the vertical axis, for each group on the horizontal axis. High OUV scores indicate strong bias in genomic hexanucleotide usage, while low scores imply more random DNA composition. Free-living archaea and bacteria (groups 5 and 7) obtain higher average OUV scores than host-associated (groups 1 and 3), indicating pronounced differences in mutational pressures in the respective environments. Average AT content was considerably higher in the host-associated groups than in the free-living.
Bohlin et al. BMC Genomics 2009 10:487 doi:10.1186/1471-2164-10-487