Cranberry proanthocyanidins have anti-biofilm properties against Pseudomonas aeruginosa

Abstract

BackgroundBacteria within a biofilm are phenotypically more resistant to antibiotics, desiccation, and the host immune system, making it an important virulence factor for many microbes. Cranberry juice has long been used to prevent infections of the urinary tract, which are often related to biofilm formation. Recent studies have found that the A-type proanthocyanidins from cranberries have anti-biofilm properties against Escherichia coli.MethodsUsing crystal violet biofilm staining, resazurin metabolism assays, and confocal imaging, we examined the ability of A-type proanthocyanidins (PACs) to disrupt the biofilm formation of Pseudomonas aeruginosa. We used mass spectrometry to analyze the proteomic effects of PAC treatment. We also performed synergy assays and in vitro and in vivo infections to determine whether PACs, alone and in combination with gentamicin, could contribute to the killing of P. aeruginosa and the survival of cell lines and G. mellonella.ResultsCranberry PACs reduced P. aeruginosa swarming motility. Cranberry PACs significantly disrupted the biofilm formation of P. aeruginosa. Proteomics analysis revealed significantly different proteins expressed following PAC treatment. In addition, we found that PACs potentiated the antibiotic activity of gentamicin in an in vivo model of infection using G. mellonella.ConclusionsResults suggest that A-type proanthocyanidins may be a useful therapeutic against the biofilm-mediated infections caused by P. aeruginosa and should be further tested.Electronic supplementary materialThe online version of this article (doi:10.1186/1472-6882-14-499) contains supplementary material, which is available to authorized users.

In vitroEffects of Anthocyanidins on Sinonasal Epithelial Nitric Oxide Production and Bacterial Physiology

“…Although a statistically significant reduction in S. aureus biofilm growth was seen with keracyanin, it is unclear whether this small decrease (Ͻ1 log) in vitro would result in clinically significant biofilm reduction in vivo. Cranberry proanthocyanidins, another flavonoid class, were previously shown to have antibiofilm properties 76 and block P. aeruginosa swarming, 77 which indicates that they may be more useful as therapeutics than anthocyanidins.…”

Transcriptomic Analyses Elucidate Adaptive Differences of Closely Related Strains of Pseudomonas aeruginosa in Fuel

“…11a), and the SNP in the promoter apparently plays a role in the expression and regulation of this gene. Interestingly, a published study using a pathogenic strain of P. aeruginosa showed that PA5359 was upregulated in the presence of proanthocyanidins and was implicated in biofilm formation (38). Bioinformatic analysis revealed that PA5359 is a predicted lipoprotein gene with a conserved Yx(FWY)xxD motif of unknown function (COG4315), shared with the bacterial adhesins.…”

Proanthocyanidin Interferes with Intrinsic Antibiotic Resistance Mechanisms of Gram‐Negative Bacteria

“…Here, we report that a purified cranberry proanthocyanidin (cPAC) fraction potentiates the activity of a broad range of antibiotic classes against the opportunistic pathogens Escherichia coli, Proteus mirabilis, and Pseudomonas aeruginosa. [6,7] cPAC are condensed tannins that can hinder bacterial attachment to cellular or biomaterial surfaces, [8][9][10][11] impair bacterial motility, [12][13][14][15][16][17] induce a state of iron limitation, [18] and interfere with quorum sensing. Remarkably, when combined with tetracycline, cPAC was able to completely prevent the evolution of resistance in E. coli and P. aeruginosa.…”

“…[6,7] cPAC are condensed tannins that can hinder bacterial attachment to cellular or biomaterial surfaces, [8][9][10][11] impair bacterial motility, [12][13][14][15][16][17] induce a state of iron limitation, [18] and interfere with quorum sensing. [6,7] cPAC are condensed tannins that can hinder bacterial attachment to cellular or biomaterial surfaces, [8][9][10][11] impair bacterial motility, [12][13][14][15][16][17] induce a state of iron limitation, [18] and interfere with quorum sensing.…”