FIG. 2.

Dendrogram of the 16S rRNA clones identified within the drinking water bacterial community DNA, showing the relationship to the closest known relatives. Only the proteobacterial lineages species are depicted. (A) Alpha-proteobacterial lineage; (B) beta-proteobacterial lineage; (C) gamma-protebacterial lineage; (D) delta-proteobacterial lineage. The phylogenetic trees were calculated with the software package MEGA version 2.1 (Molecular Evolutionary Genetics Analysis software, Arizona State University, Tempe, Ariz.) and verified with the Phylip software package from the Ribosomal Database Project (RDP) (18). Only high-quality sequences from the 16S rRNA gene clones were included in the calculations, and the hypervariable regions in the 16S rRNA molecule were excluded from the calculations. Numbers indicate data from a bootstrap analysis, and values below 50% are not indicated.