Israeli scientists at the Weizmann Institute have discovered that microorganisms can be “taught” to respond to their environments. They say the discovery could help genetically engineer microorganisms to produce biofuels.
The researchers found that E. coli bacteria, which are naturally found in the human digestive tract, are genetically conditioned to “know” that humans excrete the sugar maltose shortly after excreting the sugar lactose. When the bacteria encounter lactose, their system prepares for maltose to follow.
The groundbreaking research appears in this month’s edition of Nature. Professor Yitzhak Pilpel and doctoral student Amir Mitchell of the Weizmann Institute of Science in Rehovot joined up with Professor Martin Kupiec and Gal Romano of Tel Aviv University in the study.
The scientists compared the bacteria’s response to that of a dog. When a dog learns that a bell is always followed up by food, he begins to salivate simply upon the ring of the bell. When the dog stops receiving food after the bell, he no longer salivates to the ring.
Similarly, when the researchers withheld maltose from bacteria after they received lactose, after a few months the bacteria had evolved to stop activating their maltose genes. The research group also found that wine yeast acted in a similar way.
“In both evolution and learning," researcher Mitchell said, "the organism adapts its responses to environmental cues, improving its ability to survive."
The scientific team plans on a number of new tests for their model and new avenues of experimentation based on the insights they gained. They think their research could help genetically engineer microorganisms to ferment plant materials in the production of biofuels.