FIG. 3.

16S rRNA gene maximum parsimony tree for representative sequences obtained in this study (bold type) and sequences retrieved from the database. Sequences from this study in the tree represent groups of sequences that shared more than 96% identity; the numbers in parentheses indicate the numbers of sequences in the groups. Asterisks indicate known phototrophic species, and number signs indicate previously isolated and described species. The bootstrap values at the nodes are percentages based on 1,000 replications. Sequences from this study, as well as LO4675, AJ09636, and AJ309642, were excluded from the bootstrap analysis. Group I represents sequences recovered in this study, which formed a separate clade that included H. oregonesis (a chlorosome-less, BChla- but not BChlc- or BChld-producing species) and “Candidatus Chlorothrix” (chlorosome-containing, BChla- and BChlc-producing species); group II represents sequences obtained in this study that formed a clade with Chloroflexus, Chloronema, and Oscillochloris (chlorosome-containing, BChla- plus BChlc- or BChld-producing species). Groups III to VIII represent sequences from this study which cluster with sequences distantly related to the family Chloroflexaceae but are still in the phylum Chloroflexi.