Strange replication method and unusual genetic sequence among the mysteries
Courtesy of Chantal Abergel and Jean-Michel Claverie
The largest virus ever identified has been found on the seafloor off the coast of Chile. Pandoravirus salinus is about twice as long as the previous record holder, Megavirus chilensis, with a genome that is twice as large. That makes P. salinus larger than the smallest bacteria.
Beyond its impressive size, the Pandoravirus is strange in some other ways. Rather than reproducing by first making a viral coat and then filling it in or by building its coat around genetic material, P. salinus builds its insides and outsides simultaneously, starting at one end of the horseshoe-shaped viral particle and finishing at the other. What’s more, only 7 percent of the virus’s genes match any known gene sequences, researchers report in the July 19 Science.