The bacterial immune system has been hijacked by scientists to block genes that resists viruses and other foreign invaders. This effort has revealed a powerful new tool that has important implications for biotechnology and biomedical research.
A team of University of Georgia researchers has discovered how to harness the adaptable bacterial immune system to selectively target and silence genes.
"Scientists study bacteria and other microorganisms to understand essential life processes as well as to improve their use in the safe production of foods, biofuels and pharmaceuticals, and to fight those that cause disease," said Michael Terns, a professor in the departments of biochemistry and molecular biology, and genetics in the UGA Franklin College of Arts and Sciences.
"And now we have a new way to engineer bacteria to decrease or even eliminate the expression of the genes of our choosing," he stated.
The bacterial immune system consists of two components. The first is an RNA (a molecule that, like DNA, contains genetic information) that acts as a homing signal to target a virus or another cellular invader.
The second component is a complex of proteins that cleaves the invader's genetic material.
Using customized CRISPR RNAs with a modified homing signal, the scientists were able to destroy the message for a protein that is responsible for resistance to the most commonly prescribed family of antibiotics, the beta-lactam antibiotics (that includes, for example, amoxicillin).
"In this study we identified the key features of the RNAs that the system normally uses, and then showed that using this information we can program the system with engineered 'homing' RNAs to destroy new targets," Becky Terns, co-leader of the UGA team said.
"New targets would go beyond viruses and other invaders to include essentially any gene present in the organism being studied.
"And because we have defined the components of this system, it is possible that we can introduce it into organisms that do not already possess it to further expand the potential industrial and biomedical applications," she added.
The study has been recently published in online edition of the journal Molecular Cell.