Communication breakdown: New strategy may be valid alternative to traditional antibiotics

Jul 30, 2009

Certainly there is strength in numbers, but only if those numbers can effectively communicate with one another. Now, a new study finds that administration of a novel small molecule which effectively disrupts a key bacterial communication process protects an animal host from infection. The research, published by Cell Press in the July 31st issue of the journal Molecular Cell, may lead to more effective treatments for bacterial infection that won't encourage growth of treatment resistant bacteria.

Bacteria use a process called "quorum sensing" to communicate information about population density and to synchronously engage in group behaviors that promote bacterial pathogenesis. "Quorum sensing allows to collectively carry out tasks that would be unsuccessful if carried out by an individual bacterium acting alone," explains senior study author Dr. Bonnie L. Bassler from the Howard Hughes Medical Institute and the Department of at Princeton University.

During the process of quorum sensing, bacteria communicate via chemical signals called autoinducers. Autoinducers bind to receptors, called LuxR-type proteins, located inside the bacteria, or to receptors called LuxN proteins located in the bacterial membrane. In an earlier study, Dr. Bassler and colleagues discovered a class of small molecules that prevented a key autoinducer called acylhomoserine lactone (AHL) from binding to LuxN. Although LuxN and LuxR are not structurally similar, Dr. Bassler's team hypothesized that since both bind to AHLs, both may respond to the small molecule antagonists.

In the current study, the researchers demonstrated that the small molecule previously shown to block LuxN-type receptors is also a potent antagonist of LuxR receptors. This finding was somewhat surprising as these proteins are not evolutionarily related and exhibit vast differences in receptor localization, structure and signaling mechanisms. Importantly, the most potent antagonist protected nematode worms from quorum sensing-mediated killing by Chromobacterium violaceum, a human pathogen that frequently infects people through lacerated skin.

"Our results make a strong case and provide compelling evidence that an anti-quorum-sensing strategy is a valid alternative to traditional antibiotics and that there is merit to pursuing the clinical relevance of such strategies," offers Dr. Bassler. The work is also significant in that treatments based on disruption of quorum sensing interfere only with bacterial signaling and not growth, potentially minimizing the sometimes devastating development of bacteria that are resistant to treatment.

Source: Cell Press (news : web)

Explore further: Scientists unlock tangled mysteries of DNA

add to favorites email to friend print save as pdf

Related Stories

Toward a Rosetta Stone for Microbes' Secret Language

Dec 10, 2007

Scientists are on the verge of decoding the special chemical language that bacteria use to “talk” to each other, British researchers report in a commentary article that appeared in the November issue of ...

Scientists break cholera's lines of communication

Nov 14, 2007

A team of Princeton scientists has discovered a key mechanism in how bacteria communicate with each other, a pivotal breakthrough that could lead to treatments for cholera and other bacterial diseases.

Recommended for you

Scientists unlock tangled mysteries of DNA

9 hours ago

Chromosomal proteins hold the key to our DNA and they are changing, according to Jose Eirin-Lopez, marine sciences professor in the Florida International University Department of Biological Sciences.

Human and animal interaction identified in the viking age

14 hours ago

Since 2001, ancient DNA has been used in paleoparasitological studies to identify eggs found in soil samples from prehistoric periods, because identification cannot be done by morphological study alone. The species of human ...

User comments : 1

Adjust slider to filter visible comments by rank

Display comments: newest first

PPihkala
not rated yet Jul 30, 2009
And what would be the downsides of this approach? How does such a microbial fighter affect our microbiota inside each of our guts?

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.