Fig. 2

SPRUCE virus–host linkages according to host phylogeny. Unrooted phylogenetic tree (concatenated predicted protein alignment of 43 marker genes defined by CheckM [72]) of microbial host metagenome-assembled genomes (MAGs) with at least one vOTU (green and orange circles) linked via CRISPR sequence homology. Branch lengths represent the expected number of substitutions per site. Lines between black circles and squares with orange or green circles link vOTUs to predicted host MAGs. Colored triangles indicate the MAG genus (the same color is the same genus, except for grey triangles, for which the corresponding MAG could only be classified to the family level). Asterisk indicates vOTUs in the same genus-level viral cluster (VC); remaining vOTUs were all in distinct VCs. Bootstrap support values are shown as circles on nodes, black circles indicate support ≥ 95%, grey indicates support between 65 and 95%. A pound sign inside an orange or green circle indicates a one-nucleotide CRISPR spacer-protospacer mismatch