FIG. 4.
Phylogenetic tree showing sequences recovered from heavy (13C-enriched) fractions in this study and their closest relatives. Clones from this study are shown in bold and follow the naming scheme of growth substrate, number of days incubated (2d, 2 days; 7d, 7 days), and a number assigned to each clone for identification purposes. The percentage of screened clones represented by each group of sequences in each of the clone libraries is shown to the right of the tree. Reference sequences are shown in normal or italic font with the GenBank accession number in parentheses. The tree was based on the complete sequence of the amplified portions of the 16S rRNA gene (∼1,500 bp). Some nodes are marked with either a closed or open circle indicating greater than 50 or 95% bootstrap support, respectively. SAL, salicylate; NAP, naphthalene; PHE, phenanthrene.