Fig. 1: Comparison of cyanopodovirus genomes and their auxiliary metabolic genes.

A. Cyanopodovirus genomes. The phylogenetic tree on the left was generated from the amino acid sequences of the concatenated nine core genes shared by the 39 cyanopodoviruses using a maximum likelihood method. A black dot in a branch indicated bootstrap values larger than 80%. The scale bar represented 0.3 fixed mutations per amino acid position. The names of cyanopodoviruses isolated in this study were shown in red, and those of other phages were shown in black. Cyanophages belonging to different clades were shaded by different colors: orange for MPP-C clade, blue for MPP-B, pink for MPP-A, and grey for P-RSP2. In the MPP-C clade, P-SCSP1a was shown as a representative of cyanophages P-SCSP1a to P-SCSP1u, which share highly similar genomic organizations. In each cyanophage genome, different colors indicated genes with different functions: DNA pol in red, other genes related to DNA metabolism in purple, auxiliary metabolic genes (AMGs) in green, RNA pol in light brown, structural genes in light blue, DNA packaging genes in dark blue, integrase gene in pink, lysozyme gene in dark brown, transcriptional regulator genes in light brown, and genes with unknown function in grey. Three classes of genes, which was shown to be sequentially transcribed in cyanophage P-SSP7, were indicated below the P-SSP7 genome. Abbreviation: SSB, single-stranded DNA binding protein. B Auxiliary metabolic genes in cyanopodovirus genomes. Green and white circles indicated the presence and absence of a gene, respectively. Gene abbreviations: psbA, photosystem II D1 protein; hli, high light inducible protein; MazG, pyrophosphatase; rnr, ribonucleotide reductase; talC, transaldolase; thyX, thymidylate synthase.