Naslov
Subinhibitory concentration of tobramycin affects the RhlI/R quorum sensing system in a Pseudomonas aeruginosa environmental isolate

Autori
Babić, Fedora ; Venturi Vittorio ; Maravić Vlahoviček, Gordana

Vrsta, podvrsta i kategorija rada
Sažeci sa skupova, sažetak, znanstveni

Izvornik
Book of Abstracts / Kovarik, Zrinka ; Varljen, Jadranka - Rijeka : Hrvatsko društvo za biokemiju i molekularnu biologiju (HDBMB), 2010

Skup
10th Congress of the Croatian Society of Biochemistry and Molecular Biology “The Secret Life of Biomolecules”

Mjesto i datum
Opatija, Hrvatska, 15.09.2010. - 18.09.2010

Vrsta sudjelovanja
Pozvano predavanje

Vrsta recenzije
Domaća recenzija

Ključne riječi
quorum sensing; tobramycin; Pseudomonas aeruginosa PUPa3; aminoglycoside resistance methyltransferases

Sažetak
Although antibiotics have long been known to have multiple therapeutic effects on bacterial cells causing killing or inhibiting microbial growth, recently it has been shown that at low concentrations they can act as signaling molecules affecting gene expression in bacterial communities. A few studies have demonstrated the effect of tobramycin as a signal molecule on gene expression at the transcriptional level and its effect on bacterial physiology and virulence. These have shown that subinhibitory concentrations (SICs) of tobramycin induce biofilm formation and enhance the capabilities of P. aeruginosa to colonize specific environments. In this study it was determined whether tobramycin sensing/response at SICs was affecting the two independent AHL cell-cell signaling systems known as quorum sensing systems in an environmental P. aeruginosa strain. It is reasonable to assume that P. aeruginosa encounters tobramycin in nature since it is produced by its niche mate Streptomyces tenebrarius. Environmental P. aeruginosa strain PUPa3 was grown in the presence of difference concentrations of tobramycin and it was determined at which highest concentration SIC, growth, total protein levels and translation efficiency were not affected. At SIC it was then established if phenotypes related to quorum sensing were altered. It was established that SICs of tobramycin inhibited the RhlI/R system by reducing levels of C4-HSL production. This effect was not due to a decrease of rhlI transcription and required tobramycin-ribosome interaction. In conclusion, we show that tobramycin signaling occurs in P. aeruginosa and that different strains can have a different response. Understanding the tobramycin response by an environmental P. aeruginosa will highlight possible inter-species signaling taking place in nature and can possible also have important implications in the mode of utilization for human use of this very important antibiotic.

Izvorni jezik
Engleski

Znanstvena područja
Biologija

POVEZANOST RADA