Figure 3From: CRISPR-Cas systems in the marine actinomycete Salinispora: linkages with phage defense, microdiversity and biogeographySubclade-specific spacer content in S. arenicola phylotype B. Alignment of spacers from a homologous CRISPR locus present in all four S. arenicola phylotype B strains. The phylogenetic relationships among the four strains are depicted on the right. Spacers are indicated by rectangles arranged from the oldest (trailer end; right) to the most recent spacers (leader end; left). Vertically aligned spacers are identical and separated by subclade-specific groups of spacers (1, 2, 3), which were likely deleted from the respective other lineage or selectively acquired.Back to article page