Whenever humans create a new antibiotic, deadly bacteria can counter it by turning into new, indestructible super-bugs.
That's why bacterial infection is the number one killer in hospitals today. But new research from Tel Aviv University may give drug developers the upper hand in outsmarting bacteria once and for all.
The secret weapon against a colony of bacteria may be to stress it with its own protection system, which forces it to reduce its population through cannibalism.
"Our studies suggest this is a new way to fight off bacteria," says Prof. Eshel Ben-Jacob, an award-winning scientist from Tel Aviv University's School of Physics and Astronomy. "If we expose the entire colony to the very same chemical signals that the bacteria produce to fend off competition, they'll do the work for us and kill each other. This strategy seems very promising –– it's highly unlikely that the bacteria will develop resistance to a compound that they themselves produce."
Cannibalism among bacteria, explains Prof. Ben-Jacob, is a strange cooperative behavior elicited under stress. In response to stressors such as starvation, heat shock and harmful chemicals, the bacteria reduce their population with a chemical that kills sister cells in the colony.
"It works in much the same way that organisms reduce production of some of their cells when under starvation," says Prof. Ben-Jacob. "But what's most interesting among bacteria is that they appear to develop a rudimentary form of social intelligence, reflected in a sophisticated and delicate chemical dialogue conducted to guarantee that only a fraction of the cells are killed."
The researchers' findings, published this month in the Proceedings of the National Academy of Sciences , were carried out in collaboration with a group from Texas University led by Prof. Harry Swinney and his post-doctoral fellow Dr. Avraham Be'er, formerly of Tel Aviv University. Prof. Ben-Jacob believes that the discoveries offer new hope for fighting both bacterial infections of today and the super-super-bugs of the future.
In the current study, the researchers investigated what happens when two sibling colonies of bacteria -- Paenibacillus dendritiformis (a special strain of social bacteria discovered by Prof. Ben-Jacob) -- are grown side by side on a hard surface with limited nutrients. Surprisingly, the two colonies not only inhibited each other from growing into the territory between them but induced the death of those cells close to the border, researchers found.