Figure 6. Phylogenetic tree based on the archaeal 16S rRNA gene and related type strain sequences using the neighbor-joining method.

The bootstrap values are given at nodes when >50%. The sequence of Thermococcus mexicalis (Z75218) was used as the outgroup. Scale bar, 2% estimated difference in nucleotide sequence. Numbers in the first parenthesis indicate GenBank number of type clone, the second represent the length of in silico T-RFs; and the thrid denote the clone number, the “light” clone sequences were labeled on a light gray background and the “heavy” were underlined on a dark gray background.