Viruses found themselves living beings

Scientists have shown that viruses are living things, and have evolved from the same common ancestor as the cells of animals and plants. A new study on this subject is presented in the journal Science Advances.

Biologists Gustavo Caetano-Anoles (Gustavo Caetano-Anollés) and Arshan Nasir (Arshan Nasir) compared the protein structure of the 3460 and 1620 viruses cells. These are the types of folding proteins that remain stable even with changes in the genetic code - that makes these structures extremely valuable source of information about ancient evolutionary history of viruses and cells.

The researchers found 442 common types of folds and 66 unique structures of viruses: this proportion is characteristic of related organisms separated from a common ancestor some time ago.

Many researchers are denied the right to be called viruses living beings, since they can not reproduce on their own (and only infect foreign cells), and they have no metabolism. However, Caetano Anoles and Nasir sure that viruses simply a way of life different from other organisms.

"They are living organisms that survive an unusual method, need to infect the cell. In the end, it's not too different from the life cycle of certain parasitic bacteria "- scientists say.

In addition, the true nature of viruses Caetano Anoles and Nasir urged to consider not virions and viral "factories" in the infected cells. Production of the latest new virions, going to the capture of other cells, the researchers believe the analogue reproduction of "ordinary" organisms (production of gametes, fertilize each cell).

Hypothetical common ancestor of modern viruses and cell biologists call protovirokletkoy, and believe that it was a primitive model of the modern "virus factories". In the future, the selection pressure caused protovirokletki trim its size and the amount of the genome - so perhaps any viruses.