Abstract
<p> <p id="x-x-p-1"> Phages play a key role in the marine environment by regulating the transfer of energy between trophic levels and influencing global carbon and nutrient cycles. The diversity of marine phage communities remains difficult to characterize because of the lack of a signature gene common to all phages. Recent studies have demonstrated the presence of host-derived auxiliary metabolic genes in phage genomes, such as those belonging to the Pho regulon, which regulates phosphate uptake and metabolism under low-phosphate conditions. Among the completely sequenced phage genomes in GenBank, this study identified Pho regulon genes in nearly 40% of the marine phage genomes, while only 4% of nonmarine phage genomes contained these genes. While several Pho regulon genes were identified, <em> phoH </em> was the most prevalent, appearing in 42 out of 602 completely sequenced phage genomes. Phylogenetic analysis demonstrated that phage <em> phoH </em> sequences formed a cluster distinct from those of their bacterial hosts. PCR primers designed to amplify a region of the <em> phoH </em> gene were used to determine the diversity of phage <em> phoH </em> sequences throughout a depth profile in the Sargasso Sea and at six locations worldwide. <em> phoH </em> was present at all sites examined, and a high diversity of <em> phoH </em> sequences was recovered. Most <em> phoH </em> sequences belonged to clusters without any cultured representatives. Each depth and geographic location had a distinct <em> phoH </em> composition, although most <em> phoH </em> clusters were recovered from multiple sites. Overall, <em> phoH </em> is an effective signature gene for examining phage diversity in the marine environment. </p></p>
Original language | American English |
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Journal | Applied and Environmental Microbiology |
Volume | 77 |
DOIs | |
State | Published - Jan 1 2011 |
Disciplines
- Life Sciences