as their name suggests, giant viruses are larger than many bacterial and eukaryotic cells. They were first discovered in 2003, and the true breadth of their diversity remains unknown. In a study led by researchers at the U.S. Department of Energy Joint Genome Institute (DOE JGI), a DOE Office of Science user facility, a new group of giant viruses has been uncovered after sifting through complex genetic datasets. Dubbed Klosneuviruses, the giant virus contains a more complete set of translation machinery genes than any other virus known to date. Paper. – Frederik Schulz, Natalya Yutin, Natalia N. Ivanova, Davi R. Ortega, Tae Kwon Lee, Julia Vierheilig, Holger Daims, Matthias Horn, Michael Wagner, Grant J. Jensen, Nikos C. Kyrpides, Eugene V. Koonin, Tanja Woyke. Giant viruses with an expanded complement of translation system components. Science, 2017; 356 (6333): 82 DOI: 10.1126/science.aal4657 More.
See also: Did giant viruses evolve from smaller viruses? Or devolve from cells?
Here is a site on giant viruses.
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