Abundant SAR11 viruses in the ocean
The most recent paper from our lab details the discovery of four new phage which infect Pelagibacter (SAR11). What makes this discovery so compelling is that up until now, no phage for SAR11 had been observed, and some even postulated that SAR11 may be immune to viral infection. In fact, not only do SAR11 phage, termed Pelagiphage, exist, one of these, HTVC010P is more abundant than any previously described marine phage. This makes sense intuitively since SAR11 is the most abundant microorganism, but the discovery is a testament to the value of culture-based techniques for discovering novel phage. HTVC010P is extremely divergent from all characterized phage, which is what we believe has prevented its being noticed in metagenomic libraries prior. However, with the genome in hand, we were able to find it everywhere, and sometimes with startlingly high percent identity values, especially for a virus. Dr. Yanlin Zhao isolated three of the phage, including HTVC010P and Dr. Mike Schwalbach isolated a fourth. Dr. Ben Temperton did the bulk of the metagenomic analysis and manuscript preparation, and I contributed phylogenetic analyses and some metagenomics. The wonderful microscopy images were contributed by Thomas Deerinck and Mark Ellisman at the National Center for Microscopy and Imaging Research. Importantly, Dr. Matt Sullivan at the University of Arizona contributed metagenomic datasets for quantitative viral analysis.
Zhao, Yanlin*, Ben Temperton*, J. Cameron Thrash, Michael S. Schwalbach, Kevin L. Vergin, Zachary C. Landry, Mark Ellisman, Tom Deerinck, Matthew B. Sullivan and Stephen J. Giovannoni. (2013) Abundant SAR11 viruses in the ocean. Nature 494(7437): 357-360. doi: 10.1038/nature11921. (*Equal contribution)