FIG. 5.

Phylogenetic relationships of the 18 archaeal 16S rRNA gene sequences obtained from the GH-4 clone library. The tree was inferred by neighbor-joining analysis of 402 homologous positions of sequence from each organism or clone. Aquifex pyrophilus was used as the outgroup. Numbers on the nodes are the bootstrap values (percentages) based on 1,000 replicates. Scale bar indicates the estimated number of base changes per nucleotide sequence position. Bold type indicates GH-4 clones, with their prevalence in the clone library.