FIG 2.

Phylogenetic tree based on 16S rRNA gene sequences of the genus Nitrotoga and representatives of the family Gallionellaceae as the outgroup. The tree was constructed using the maximum likelihood algorithm. Bootstrap values at the branch nodes were iterated 1,000 times. Sequences of Nitrotoga obtained in this study and other enriched cultures are in bold. The scale bar corresponds to 1% estimated sequence divergence. Accession numbers are shown to the right of the organism names/descriptions. DO, dissolved oxygen.