FIG 6.

Phylogenetic analysis of viral hosts and sequence alignment of the sites of integration. (A) A 16S rRNA gene-based phylogenetic tree of Sulfolobus sp. strain E5-1-F, Sulfolobus sp. strain E11-6, and 17 additional Sulfolobus strains constructed by using the neighbor-joining method (45). The percentages of replicate trees in which the associated taxa clustered together in the bootstrap test (1,000 replicates) are shown next to the branches (50). The evolutionary distances are in units of the number of base substitutions per site. (B) Sequence alignment of the sites of integration of SSV19-SSV22 with the 3′ terminal part of the tRNA genes, which contain the potential sites of viral integration, from their hosts.