In DepthEvolution

Cell-like giant viruses found

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Science  07 Apr 2017:
Vol. 356, Issue 6333, pp. 15-16
DOI: 10.1126/science.356.6333.15

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Summary

Researchers used to think that viruses were small and simple, but they've identified giant viruses that are larger than many bacteria and carry more genes. Now, scientists report that they've uncovered genomes of the most cell-like viruses discovered so far. Compared with previous giant viruses, the new viruses have more of the genes necessary for protein synthesis, including a complete set of genes that code for enzymes that ensure delivery of amino acids to sites of protein synthesis. The researchers' analysis of the viruses' gene sequences challenges a controversial hypothesis that giant viruses descended from cells and represent a new domain, or a new branch on the tree of life.