## 2 Overview of Cyanphage
\begin{table}
\begin{tabular}{c c c c c c} \hline \hline
**Protein Function** & **Protein** & **Ratios** & **Protein Function** & **Protein** & **Ratios** \\ \hline Photosynthesis & photosystem II reaction center & & & & \\ protein PsbA/D1 & 111/153 & Methylation & DNA methylase & 23/153 \\ photosystem II D2 protein & 77/153 & & DNA adenine methylase Dam & 55/153 \\ physicochemical Hydrocarbon & 16/153 & & cytosine methyltransferase & 11/153 \\ oxidoreductase (PsyA) & & & & \\ ferredoxin (Petf) & 44/153 & & type II N-methyl DNA methyltransferase & 13/153 \\ phycohulin lyase (CoeT) & 31/153 & & phage host specificity protein & 3/153 \\ phycohulin synthesis (PetS) & 9/153 & & & \\ phycoerythrobulin & 4/153 & Phosphate metabolism & phosphate-starvation-inducible & 101/153 \\ plastoquinol terminal oxidase ProX & 35/153 & & phosphate-induced stress protein & 2/153 \\ plastocyanin (PetE) & 70/153 & & phosphate ABC transporter & 31/153 \\ heme oxygenase (Ho) & 8/153 & & phosphate-binding protein PsfS & 31/153 \\ hil gene family /hil-hilguht inducible protein & 90/153 & & & \\ thioredoxinoxin & 5/153 & Regulatory factor & CooS/cob/cobA & 39/153 \\ file bifunctional protein & 1/153 & & RNA polymerase sigma factor Pbcol/RpoS & 65/153 \\
20G-F(ell) oxygenase family oxidoreductase & 76/153 & & ERF mediumly & 1/153 \\ NADH dehydrogenase subunit I & 1/153 & & MacF & 64/153 \\ NAD synthetase & 24/153 & & RegA photosynthetic apparatus regulatory & 48/153 \\ carbon metabolism & carbohydratesterase & 24/153 & & transcriptional regulator & 7/153 \\ FAD-dependent thymidylate & 95/153 & & late promoter transcriptional accessory protein & 41/153 \\ synthesobase family protein TaC in & 96/153 & & CP12 carbon metabolic regulator & 31/153 \\ this family & & & & \\ glucose \& \& & & \\ glucose \& \& & & \\ e-phosphoglucate dehydrogenase Gnd & 22/153 & & Mark family protein & 3/153 \\ UDP-glucose \& \& & & \\ acyl carrier protein ACP & 2/153 & & XRE family transcriptional regulator & 1/153 \\ fructose-6-phosphate aldolase & 1/153 & & NPJ & 48/153 \\ \hline \hline \end{tabular}
\end{table} 
Table 2: AMGs in the sequenced cyanophage genomes. Recent studies show that the encoded tRNA genes within the myocyanophage can alter the host codon translational efficiency [35; 36]. This provides a competitive advantage, enabling the myocyanophage to infect a much broader range of hosts than their podocyanophage and siphocyanophage counterparts [37; 38; 36]. The divergence of nucleotide sequences from different cyanophages may be seen through comparative genome analysis (Figure 1B). DNA polymerase and terminase are widely distributed in the podocyanophages and myocyanophages. DNA polymerase has not been discovered in most of the siphocyanophages, whereas terminase exists in most of the siphocyanophages. We based the phylogenetic analysis on the nucleotide sequences of the conserved genes, DNA polymerase and terminase, using the maximum likelihood method (ML) (Figure 1B). Generally, close genetic relationship may be seen within families, and a more distinct genetic relationship may be seen between families, though notable exceptions may be observed. The 153 fully sequenced cyanophages from NCBI comprise 33 podocyanophages, 103 myocyanophages, 15 siphocyanophages, and 2 unclassified phages. We identified and discounted all genes associated with phage replication from these sequences. In the remaining sequence data, a palette of 45 AMGs that may play a key role in altering host metabolism following infection could be seen to occur frequently. Though a few AMGs were seen to occur in only one virus, many were seen to be widely distributed across the majority of viruses that were analyzed (Figure 2), implying the importance and evolutionary advantage of the roles that they play. The 45 AMGs encoded within the cyanophages were all homologs of genes found within cyanobacteria that play a key role in cyanobacterial metabolism.