Some scientists objected, saying the resurrected virus could go on a rampage the research ministry approved the project.ġ6. Most of those embedded viruses are now extinct, but in 2005 French researchers applied for permission to resurrect one of them. In fact, scratch the whole concept of “us versus them.” Half of all human DNA originally came from viruses, which infected and embedded themselves in our ancestors’ egg and sperm cells.ġ5. Sputnik and Mamavirus suggest that they can infect other viruses, too.ġ4. Viruses are already known to infect animals, plants, fungi, protozoa, archaea, and bacteria. They like to swallow big things and so serve as a kind of mixing bowl where viruses and bacteria can swap genes.ġ3.
Amoebas turn out to be great places to seek out new viruses.
Mamavirus is so big that it has its own dependent, a satellite virus named Sputnik.ġ2. (Maybe somebody should clean those towers.)ġ1.
Mamavirus, closely related to Mimivirus but even bigger, also turned up inside an amoeba in a Paris cooling tower. Its genome is twice as big as that of any other known virus and bigger than that of many bacteria.ġ0. Mimivirus contains more than 900 genes, which encode proteins that all other viruses manage to do without. That über-virus is now called Mimivirus, so named because it mimics bacteria and because French biologist Didier Raoult, who helped sequence its genome, fondly recalled his father telling the story of “Mimi the Amoeba.”ĩ. It was so large and complex, they initially assumed it was a bacterium.Ĩ. In 1992 scientists tracking a pneumonia outbreak in England found a massive new kind of virus lurking within an amoeba inside a cooling tower. Virus comes from the Latin word for “poison” or “slimy liquid,” an apt descriptor for the bug that causes flu and the common cold.ħ. Score one for Team Living: Some viruses sneak DNA into a bacterium through its, um, sex appendage, a long tube known as a pilus. Score one for Team Nonliving: After American biochemist Wendell Stanley purified the tobacco mosaic virus into needlelike crystals of protein, he won a 1946 Nobel Prize-awarded in chemistry, not medicine.ĥ. That something, now called the tobacco mosaic virus, appears on this page (magnified and colorized).Ĥ. Scientists have been debating this issue since 1892, when Dmitry Ivanovsky, a Russian microbiologist, reported that an infection in tobacco plants spreads via something smaller than a bacterium. Viruses are not exactly dead, either: They have genes, they reproduce, and they evolve through natural selection.ģ. Viruses are not alive : They do not have cells, they cannot turn food into energy, and without a host they are just inert packets of chemicals.Ģ.
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