Quorum Quenching: Interrupting the Communication

Recent scientific evidence demonstrates the role played by certain compounds, which modify the signaling molecules that bacteria use to communicate.

In a polymicrobial community, while some bacteria are communicating with neighboring cells through signaling molecules (quorum sensing), others are interrupting the communication  (quorum quenching), thus creating a constant arms raced between intercellular communication.

Cell to cell communication through chemical signals allows bacteria to measure the population around them, develop virulence factors and increase their pathogenicity. This is an adaptive mechanism among other things, is responsible for the formation of biofilms and bacterial toxins.

Gram-negative bacterias used as a signaling molecule of Quorum Sensing (QS) to the N-acylhomoserine lactone (AHL), instead use the Gram-positive oligopeptides.

The Quorum Quenching (QQ) is the mechanism by which certain organisms interfere with communication between bacteria by modifying molecules that they use as a signal.

In the last decade have discovered enzymes that can inactivate signaling molecules (AHL) and interfere with the communication mechanism. Some of these enzymes are known as lactonases , acylases and oxidoreductases, that by modifying the AHL, generate a "confusion of the signaling", producing a non-destructive modification of signaling molecules.

Many publications have suggested that these enzymes also play an important role in the interference of AHL metabolism, detoxification, regulation of physiological functions and symbiotic interaction with the host.

While QQ has been explored as a therapy for good control of those infections, in which antibiotics are ineffective, the evidence shows that also begins to appear resistance QQ compounds tested.

The QS research has led to the discovery of tools for the design of new anti-infective therapies, which promise future biotechnology and pharmaceutical applications, although scientists recommend being careful with the QS system of bacteria, not to open another Pandora's box.

Source:http://www.mdpi.com