Small molecules that interrupt the chemical signals by which bacteria communicates by blocking the process of infection have been identified. The discovery, published in Molecular Cell, as well as representing a new option in the treatment of infections, reduces the risk of growth of bacteria strains resistant to antibiotics.
Bacteria will exchange information with a system of intercellular communication, called quorum sensing, which allows them to perceive and respond to changes in density and to coordinate actions of the group. As soon as the conditions are favorable to population growth, for example if they are within a host, the bacteria sends chemical signals to molecules that bind to receptors inside: LuxR-type proteins or proteins of the type LuxN, located on membrane of each cell. In this way the infection proceeds without hitches. "
Blocking the communications of the enemy has always been a winning weapon. The researchers searched the key to succeeding, and found in an old acquaintance. In a previous study Bassler and colleagues had discovered that a class of molecules called lactose acilomoserina (AHL), is able to compete with the signals acting on LuxN proteins, preventing them from binding to the receptor. In the recent study, researchers have realized that the AHL can also bind to proteins of the LuxR type.
In this way was brought into light the AHL the ability to bind to both receptors, although the two proteins have two completely different structure and location mechanisms.
Treatment with these molecules on nematode worms has protected them from infection due to Chromobacterium violaceum, a bacterium that causes infections in human beings also. "These results make the winning strategy of interruption of quorum sensing in bacteria, such as promoting good alternative to antibiotic treatment," concluded Bassler.