Viral metagenome isolated from Chesapeake Bay sediment. uncultured marine virus

Viruses were extracted and concentrated from Chesapeake Bay surface sediment samples that were collected on nine cruises from April 2003 to October 2005. Free DNA within the viral concentrates was removed through nuclease digestion. Subsequently, viral genomic DNA was amplified by a single 10-mer primer using randomly amplified polymorphic DNA-PCR. A clone library of RAPD-PCR amplicons was constructed using a plasmid vector (pCR8/GW/TOPO; Invitrogen) that prevents transcription of insert DNA. From this library, 518 clones were sequenced and yielded 448 high quality sequences. BLAST analyses indicated that the clone library contained a remarkably high percentage (76%) of sequences with no known homologs. Further supporting the notion that natural viral communities, including estuarine sediments, contain the greatest quantity of unknown genetic diversity. Process-level investigations of viral activity in marine sediments have shown that viruses are an active component of sediment microbial communities. Viral abundance exceeds co-existing bacterial abundance by 10 to 1,000 fold in sediment environments, and it is likely that viral processes influence the ecology of bacterial communities in aquatic sediments. These influences include alterations in the population dynamics and genotypic composition of bacterial host populations. GenBank accession numbers FJ640107-FJ640554 are viral metagenomic sequences derived from this study.