FIG 2.

Neighbor-joining phylogenetic relationships of translated DNA pol gene sequences recovered from the clone libraries, known N4-like phages, and metagenomic databases. The tree is based on the aligned amino acid sequences (ca. 130 residues). The sequences of 24 N4-like phages and 2 outgroup sequences are shown in black. The sequences recovered from metagenomic searches and upper, middle, and lower Chesapeake Bay are in green, red, purple, and blue, respectively. The clusters were defined as sequences that share greater than 80% amino acid identity. The bootstrap value was calculated with 1,000 replications. Bootstrap values of ≥50% are shown at the nodes. The scale bar represents 0.1 amino acid substitution.