Discovery of self-destruct mechanism in algae could have broad applications for antibiotics and biofuels

U of A microbiologists find first evidence of bacteria causing programmed cell death in single-celled algae.

In a discovery that could have broad applications from the development of targeted antibiotics to the production of biofuels in industry, University of Alberta biologists discovered evidence of bacteria causing apoptosis, or programmed cell death, in algae.

"It sounds odd, but programmed cell death is important to all large organisms. For any cells to differentiate, they have to be able to kill cells. For example, if you injure yourself, your scab is formed with these killed-off cells," explained U of A microbiologist Rebecca Case.

"Here at the single-cell level, we've found that small molecules are passed from bacteria into the host algae. By doing that, the bacteria are able to tell the algae to kill themselves."

Until now, apoptosis was thought to occur only in large, multicellular organisms such as animals and humans.

"It is the first documentation of true apoptosis via bacterial pathogens in microorganisms like algae," said Case, who conducted the work with PhD graduate Anna Bramucci.

Major potential

The research could help scientists discover and develop new, more fine-tuned antibiotics. Unlike traditional antibiotics, which kill all bacteria, the new antibiotics could potentially turn individual bacteria or cells on and off.

Case and her colleagues previously used this approach to find antibiotics that are effective at concentrations up to 1,000 times lower than traditional antibiotics.

"In interactions like these that occur in close proximity, you can find molecules that are effective in very small concentrations," she noted. "Going forward, that's what we want-really potent molecules."

Another area of interest is biofuels-natural fuels derived from living matter.

"Algae can also be used to create lipids for biofuels," explained Case. "If we can better understand their life cycles, we can find ways to keep them alive for longer, to produce more fuel for industry."

The study, "Phaeobacter inhibens Induces Apoptosis-Like Programmed Cell Death in Calcifying Emiliania huxleyi," was published in Scientific Reports.