Figure 5.

Organisms used in cross-species comparisons of SDR elements. The phylogenetic tree to the left of the organism names is derived from a comparison of cyanobacterial 16S rRNA sequences. Arrows point to nodes defining the heterocystous cyanobacteria (the major focus of this work, highlighted in the table) and the more encompassing clade of filamentous cyanobacteria. All genomes except those from Lyngbya and Crocosphaera have been completely sequenced. The sequences were taken from Joint Genome Institute (http://genome.jgi-psf.org/mic_home.html), CyanoBase/Kazusa (http://bacteria.kazusa.or.jp/cyano/cyanobase/), or the National Center for Biotechnology Information (http://www.ncbi.nlm.nih.gov/). In the latter case, the GenBank accession number is given. The small plasmid, pANS, of Synechococcus PCC 7942 was also taken from GenBank, accession GI:247785. The Nostoc punctiforme genome has recently been deposited in GenBank (accession no. NC_010628), with only minor differences in the annotation relative to the version used in this study. The incidence of each of SDR family (SDR1 through SDR8) is shown for each genome, represented by a plus (at least 10 occurrences), a tilde (at least one, but fewer than 10 occurrences), or nothing (0 occurrences). Published descriptions of the genomes: (A) Palenik et al. 2003, (B) Rocap et al. 2003, (C) Dufresne et al. 2003, (D) Holtman et al. 2005, (E) Nakamura et al. 2003, (F) Nakamura et al. 2002, (G) Kaneko et al. 2001, (H) Meeks et al. 2001, (I) Kaneko et al. 1996, (J) Blattner et al. 1997).