Fig. 4. Presence of Trichodesmium CRISPR systems in a phylogenomic context and Cas10 phylogenetics.

Presence or absence of CRISPR-Cas genes in a Trichodesmium MAGs and their nearest relatives phylogenomic context (A) and a maximum likelihood tree of their Cas10 protein sequences (B). In (A), the color-coded, directional shapes on the right represent detected Cas genes (yellow), CRISPR arrays (black), Cas accessory genes (purple) and hypothetical genes (gray) that were annotated by as described in the Materials and Methods. Lighter color indicates lower confidence in the annotation. Double-slashes are contig break positions near the annotated CRISPR-Cas systems, indicating that some clusters are fragmented due to breaks in the assemblies. Gene lengths are not drawn to scale. In (B), the color coding corresponds to T. thiebautii (Blue) and other relatives (Black). Cas10 protein sequences are in Supplementary Table 12.