Fig. 2.

Phylogenetic community structures based on 16S rRNA gene clone libraries of domains Archaea (A) and Bacteria (B) from ODP sediment core samples. Numbers of clones examined at each depth are indicated in parentheses. The phylogenetic affiliation of each clone sequence was determined by similarity analysis of 400–500 bp of 16S rRNA gene sequences. In each column diagram, the relative abundances of clones classified with the (sub)phylum level are shown. Bacterial community structures at Site 1225 were evaluated by sequencing 200 bp of PCR fragments obtained by denaturing gradient gel electrophoresis (DGGE) analysis, and the number of major bands is indicated in parentheses with asterisk. Phylogenetic trees involving ≈1 kbp sequences of 348 representative phylotypes are shown in Fig. 5.