Doxycycline interferes with quorum sensing-mediated virulence factors and biofilm formation in Gram-negative bacteria

作者：Husain Fohad Mabood; Ahmad Iqbal^*

来源：WORLD JOURNAL OF MICROBIOLOGY & BIOTECHNOLOGY, 2013, 29(6): 949-957.

DOI：10.1007/s11274-013-1252-1

• Quorum sensing
• Chromobacterium violaceum
• Pseudomonas aeruginosa
• Virulence factors
• Biofilm

Inhibition of quorum sensing (QS)-regulated virulence factors including biofilm is a recognized anti-pathogenic drug target. The search for safe and effective anti-QS agents is expected to be useful to combat diseases caused by multidrug-resistant bacteria. In this study, effect of a commonly used antibiotic, doxycycline on QS was evaluated using sensor strains of Chromobacterium violaceum (ATCC 12472 and CVO26) and Pseudomonas aeruginosa PAO1. Sub-MICs of doxycycline reduced QS-controlled violacein production in C. violaceum to a significant degree (70 %) and showed a significant reduction of LasB elastase (67.2 %), pyocyanin (69.1 %), chitinase (69.8 %) and protease (65 %) production and swarming motility (74 %) in P. aeruginosa PAO1 over untreated controls. Similar results were also recorded against a clinical strain of P. aeruginosa (PAF-79). Interestingly, doxycycline at respective sub-MICs (4 and 32 mu g ml(-1)) significantly reduced the biofilm-forming capability and exopolysaccharide production in both the strains of P. aeruginosa (PAO1 and PAF-79) over untreated controls. The results of this study highlight the multiple actions of doxycycline against QS-linked traits/virulence factors and its potential to attenuate virulence of P. aeruginosa.

• 出版日期2013-6