Bacterial communications in implant infections: a target for an intelligence war.

Abstract

The status of population density is communicated among bacteria by specific secreted molecules, called pheromones or autoinducers, and the control mechanism is called ""quorum-sensing"". Quorum-sensing systems regulate the expression of a panel of genes, allowing bacteria to adapt to modified environmental conditions at a high density of population. The two known different quorum systems are described as the LuxR-LuxI system in gram-negative bacteria, which uses an N-acyl-homoserine lactone (AHL) as signal, and the agr system in gram-positive bacteria, which uses a peptide-tiolactone as signal and the RNAIII as effector molecules. Both in gram-negative and in gram-positive bacteria, quorum-sensing systems regulate the expression of adhesion mechanisms (biofilm and adhesins) and virulence factors (toxins and exoenzymes) depending on population cell density. In gram-negative Pseudomonas aeruginosa, analogs of signaling molecules such as furanone analogs, are effective in attenuating bacterial virulence and controlling bacterial infections. In grampositive Staphylococcus aureus, the quorum-sensing RNAIII-inhibiting peptide (RIP), tested in vitro and in animal infection models, has been proved to inhibit virulence and prevent infections. Attenuation of bacterial virulence by quorum-sensing inhibitors, rather than by bactericidal or bacteriostatic drugs, is a highly attractive concept because these antibacterial agents are less likely to induce the development of bacterial resistance.

• Authors: J W Costerton, L Montanaro, C R Arciola
• Journal: The International journal of artificial organs (Int J Artif Organs) Vol. 30 Issue 9 Pg. 757-63 (Sep 2007) ISSN: 0391-3988 [Print] United States
• PMID: 17918119 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't, Review)

Chemical References

• Anti-Bacterial Agents

Topics

• Aliivibrio fischeri (pathogenicity)
• Anti-Bacterial Agents (pharmacology, therapeutic use)
• Bacteria (drug effects, growth & development, pathogenicity)
• Drug Resistance, Bacterial
• Humans
• Prosthesis-Related Infections (drug therapy, microbiology)
• Pseudomonas aeruginosa (pathogenicity)
• Quorum Sensing (drug effects)
• Staphylococcus aureus (pathogenicity)
• Virulence