An international research team discovered that bacteria cells use a virus and a prehistoric viral protein to attack other bacteria.

Bacteria Against Bacteria

The team made the discovery after noticing a gap between two bacteria that were moving toward each other on an agar plate. They investigated and found that the gap was caused by a virus, SW1, killing bacteria cells. They also reported that only one of the strains of bacteria carried the SW1 virus.

"It was kind of like when Alexander Fleming noticing bacteria did not grow near a fungus when he discovered penicillin in the 1920s," said Wood who led the study.

The researchers explained that a virus enters a cell and hides in the chromosome until it is ready to attack and kill. However, a mutation sometimes occurs and the virus gets stuck.

There are nine viruses that were trapped in the bacterium E. coli, for example.

The investigation also revealed that to enable the bacterium to use the virus and attack competitors, it has to use a protein fossil that it obtained from another virus millions of years ago. The bacterium needs the protein YfdM, which was stuck in the chromosome of E. coli, in order to use the SW1 virus.

Moreover, the team claimed that bacterial cells use the virus to separate their own from other bacteria.

"Bacteria are frequently thought of as living alone but instead they can forage for food as groups," said Wood. "In order to act as a group, they must be able to distinguish themselves from other bacteria."

The team stated that, if the bacterium does not detect the virus, it identified other bacteria as competitors for food and, therefore, unleash the SW1 virus to attack.

Development Of New Treatment

The researchers admitted that the processes that take place are not yet fully understood, but they believe that their findings could lead to the development of new treatment against infectious diseases.

Wood added that understanding how cells compete against each other would is an important area of study. He cited synthetic biology, for example, where several cells are involved. Scientists could make useful cells more dominant.

The study appears in the recent issue of Cell Reports.