HOUSTON -- (Sept. 15, 2010) -- In a new study this week, Rice University scientists bring the latest tools of computational biology to bear in examining how the processes of natural selection and evolution influence the way bacteria acquire immunity from disease.
The study is available online from Physical Review Letters. It builds upon one of the major discoveries made possible by molecular genetics in the past decade -- the revelation that bacteria and similar single-celled organisms have an acquired immune system.
"From a purely scientific perspective, this research is teaching us things we couldn't have imagined just a few years ago, but there's an applied interest in this work as well," said Michael Deem, the John W. Cox Professor in Biochemical and Genetic Engineering and professor of physics and astronomy at Rice. "It is believed, for instance, that the bacterial immune system uses a process akin to RNA interference to silence the disease genes it recognizes, and biotechnology companies may find it useful to develop this as a tool for silencing particular genes."
The new study by Deem and graduate student Jiankui He focused on a portion of the bacterial genome called the "CRISPR," which stands for "clustered regularly interspaced short palindromic repeats." The CRISPR contain two types of DNA sequences. One type -- short, repeating patterns that first attracted scientific interest -- is what led to the CRISPR name. But scientists more recently learned that the second type -- originally thought of as DNA "spacers" between the repeats -- is what the organism uses to recognize disease.
"Bacteria get attacked by viruses called phages, and the CRISPR contain genetic sequences from phages," Deem said. "The CRISPR system is both inheritable and programmable, meaning that some sequences may be there when the organism is first created, and new ones may also be added when new phages attack the organism during its life cyc
|Contact: Jade Boyd|