COPENHAGEN, Denmark, July 14 (UPI) -- To counteract the defects that are an unavoidable part of aging, bacteria simply proliferate. They grow and divide, grow and divide.
Until now, researchers weren't sure how a dividing cell distributed its defects.
"We wanted to investigate whether the bacteria divided symmetrically with an equal number of defects in both new individuals or whether divided asymmetrically with more defects in one new bacteria than the other," Ala Trusina, an associate professor in biocomplexity at the University of Copenhagen's Niels Bohr Institute, said in a news release.
Researchers combined lab experiments and computer models to determine which strategy is most beneficial.
When bacteria colonies were left alone and undisturbed in a lab setting, proliferating cells shared the burden of aging rather evenly. When stress was introduced, such as heat or a bacteriostatic agent, defects were distributed asymmetrically.
A few individual cells carried consequences of aging, and as a result, grew much more slowly. Their sacrifice allows other divided cells to carry on defect-free, and thus better able to persevere in the face of hardship.
"What we have found is that the asymmetry of cell division is not controlled genetically. It is a process that is controlled by the physical environment," Trusina explained. "Through collective behavior, the bacterial colony that is exposed to stress can stay young, produce more offspring and keep the colony healthier. This is completely new knowledge that has never been observed before."
The new research was published in the journal Cell Systems.