Thaindian News

Washington, Dec 26 (IANS) Bacterial cells tend to form intricately structured communities called biofilms. Until now, the mechanisms that cause isolated bacteria to suddenly aggregate into a social network were unknown. But the communication pathways have been revealed now.New insights from the lab of Harvard Medical School microbial geneticist Roberto Kolter reveal the pathways that cause such social phenomenon.

Using the non-pathogenic Bacillus subtilis as a model organism, Kolter and postdoctoral researcher Daniel Lopez discovered a group of natural, soil-based products that trigger communal behaviour in bacteria.

One molecule in particular, surfactin, is produced by B. subtilis. Biofilm formation begins when surfactin, and other similar molecules, cause bacteria to leak potassium.

As potassium levels decline, a membrane protein on the bacterium stimulates a cascade of gene activity that signals neighbouring cells to form a quorum. As a result, biofilms form, said a Harvard statement.

The authors note that it’s still unclear how biofilm formation benefits the bacteria, and they hypothesise that it might be an antibacterial defence against competing species. Still, the notion that a single small molecule can induce multicellularity intrigues the researchers.

“Typically, scientists try to discover new antibiotics through some rather blunt means, like simply looking to see if one bacterium can kill another,” says Kolter.

“This discovery of a single molecule causing such a dramatic response in bacteria hints at a new and potentially effective way to possibly discover antibiotics.”