Next Article in Journal
Marine Compound Xyloketal B Reduces Neonatal Hypoxic-Ischemic Brain Injury
Next Article in Special Issue
Marine Peptides and Their Anti-Infective Activities
Previous Article in Journal
Multiple Beneficial Lipids Including Lecithin Detected in the Edible Invasive Mollusk Crepidula fornicata from the French Northeastern Atlantic Coast
Previous Article in Special Issue
Geographic Variability and Anti-Staphylococcal Activity of the Chrysophaentins and Their Synthetic Fragments
Article Menu

Export Article

Open AccessArticle
Mar. Drugs 2015, 13(1), 1-28; doi:10.3390/md13010001

Marine-Derived Quorum-Sensing Inhibitory Activities Enhance the Antibacterial Efficacy of Tobramycin against Pseudomonas aeruginosa

1
School of Pharmacy, Queen's University Belfast, 97 Lisburn Rd, Belfast BT9 7BL, UK
2
School of Biological Sciences, Medical Biology Center, 97 Lisburn Road, Belfast BT9 7BL, UK
*
Author to whom correspondence should be addressed.
Academic Editor: Miguel Mitchell
Received: 27 October 2014 / Accepted: 15 December 2014 / Published: 24 December 2014
(This article belongs to the Special Issue Marine Anti-infective Agents)
View Full-Text   |   Download PDF [1421 KB, uploaded 24 February 2015]   |  

Abstract

Bacterial epiphytes isolated from marine eukaryotes were screened for the production of quorum sensing inhibitory compounds (QSIs). Marine isolate KS8, identified as a Pseudoalteromonas sp., was found to display strong quorum sensing inhibitory (QSI) activity against acyl homoserine lactone (AHL)-based reporter strains Chromobacterium violaceum ATCC 12472 and CV026. KS8 supernatant significantly reduced biofilm biomass during biofilm formation (−63%) and in pre-established, mature P. aeruginosa PAO1 biofilms (−33%). KS8 supernatant also caused a 0.97-log reduction (−89%) and a 2-log reduction (−99%) in PAO1 biofilm viable counts in the biofilm formation assay and the biofilm eradication assay respectively. The crude organic extract of KS8 had a minimum inhibitory concentration (MIC) of 2 mg/mL against PAO1 but no minimum bactericidal concentration (MBC) was observed over the concentration range tested (MBC > 16 mg/mL). Sub-MIC concentrations (1 mg/mL) of KS8 crude organic extract significantly reduced the quorum sensing (QS)-dependent production of both pyoverdin and pyocyanin in P. aeruginosa PAO1 without affecting growth. A combinatorial approach using tobramycin and the crude organic extract at 1 mg/mL against planktonic P. aeruginosa PAO1 was found to increase the efficacy of tobramycin ten-fold, decreasing the MIC from 0.75 to 0.075 µg/mL. These data support the validity of approaches combining conventional antibiotic therapy with non-antibiotic compounds to improve the efficacy of current treatments. View Full-Text
Keywords: antibiotic resistance; antimicrobial synergy; quorum sensing inhibitors; marine bacteria; biofilm; marine biodiscovery; tobramycin; Pseudomonas aeruginosa antibiotic resistance; antimicrobial synergy; quorum sensing inhibitors; marine bacteria; biofilm; marine biodiscovery; tobramycin; Pseudomonas aeruginosa
This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. (CC BY 4.0).

Supplementary material

Scifeed alert for new publications

Never miss any articles matching your research from any publisher
  • Get alerts for new papers matching your research
  • Find out the new papers from selected authors
  • Updated daily for 49'000+ journals and 6000+ publishers
  • Define your Scifeed now

SciFeed Share & Cite This Article

MDPI and ACS Style

Busetti, A.; Shaw, G.; Megaw, J.; Gorman, S.P.; Maggs, C.A.; Gilmore, B.F. Marine-Derived Quorum-Sensing Inhibitory Activities Enhance the Antibacterial Efficacy of Tobramycin against Pseudomonas aeruginosa. Mar. Drugs 2015, 13, 1-28.

Show more citation formats Show less citations formats

Related Articles

Article Metrics

Article Access Statistics

1

Comments

[Return to top]
Mar. Drugs EISSN 1660-3397 Published by MDPI AG, Basel, Switzerland RSS E-Mail Table of Contents Alert
Back to Top