The extracellular matrix protects Pseudomonas aeruginosa biofilms by limiting the penetration of tobramycin.
Boo Shan Tseng,Wei Zhang,Joe J. Harrison,Tam P. Quach,Jisun L. Song,Jon Penterman,Jon Penterman,Pradeep K. Singh,David L. Chopp,Aaron I. Packman,Matthew R. Parsek +10 more
TLDR
It is proposed that tobramycin sequestration at the biofilm periphery is an important mechanism in protecting metabolically active cells that lie just below the zone of sequestration.Abstract:
Biofilm cells are less susceptible to antimicrobials than their planktonic counterparts. While this phenomenon is multifactorial, the ability of the matrix to reduce antibiotic penetration into the biofilm is thought to be of limited importance studies suggest that antibiotics move fairly rapidly through biofilms. In this study, we monitored the transport of two clinically relevant antibiotics, tobramycin and ciprofloxacin, into non-mucoid Pseudomonas aeruginosa biofilms. To our surprise, we found that the positively charged antibiotic tobramycin is sequestered to the biofilm periphery, while the neutral antibiotic ciprofloxacin readily penetrated. We provide evidence that tobramycin in the biofilm periphery both stimulated a localized stress response and killed bacteria in these regions but not in the underlying biofilm. Although it is unclear which matrix component binds tobramycin, its penetration was increased by the addition of cations in a dose-dependent manner, which led to increased biofilm death. These data suggest that ionic interactions of tobramycin with the biofilm matrix limit its penetration. We propose that tobramycin sequestration at the biofilm periphery is an important mechanism in protecting metabolically active cells that lie just below the zone of sequestration.read more
Citations
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Molecular mechanisms of biofilm-based antibiotic resistance and tolerance in pathogenic bacteria
Clayton W. Hall,Thien-Fah Mah +1 more
TL;DR: This review summarises both historical and recent scientific data in support of the known biofilm resistance and tolerance mechanisms and suggestions for future work in the field are provided.
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Biofilm-Related Infections: Bridging the Gap between Clinical Management and Fundamental Aspects of Recalcitrance toward Antibiotics
TL;DR: This review presents the current understanding of the molecular mechanisms of biofilm recalcitrance toward antibiotics and describes how recent progress has improved the capacity to design original and efficient strategies to prevent or eradicate biofilm-related infections.
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Bacterial biofilm formation on implantable devices and approaches to its treatment and prevention
TL;DR: A brief overview of concepts of bacterial biofilm formation, current state-of-the-art therapeutic approaches for preventing and treating biofilms, and the prevalence of such infections on medical devices is reviewed.
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Nanomaterial-based therapeutics for antibiotic-resistant bacterial infections
Jessa Marie Makabenta,Ahmed Nabawy,Cheng-Hsuan Li,Suzannah M. Schmidt-Malan,Robin Patel,Vincent M. Rotello +5 more
TL;DR: The mechanisms by which nanomaterials can be used to target antibiotic-resistant bacterial infections are discussed, design elements and properties of nanomMaterials that can be engineered to enhance potency are highlighted, and recent progress and remaining challenges for clinical implementation are explored.
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Molecular mechanisms of antimicrobial tolerance and resistance in bacterial and fungal biofilms
TL;DR: Three mechanisms that play an important role in biofilm survival are discussed, found both in bacterial and fungal biofilms and are often surprisingly similar between distantly related organisms.
References
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Journal ArticleDOI
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Matthew S. Byrd,Irina Sadovskaya,Evgueny Vinogradov,Haiping Lu,April B. Sprinkle,Stephen H. Richardson,Luyan Z. Ma,Brad Ralston,Matthew R. Parsek,Erin M. Anderson,Joseph S. Lam,Daniel J. Wozniak +11 more
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Journal ArticleDOI
Putative Exopolysaccharide Synthesis Genes Influence Pseudomonas aeruginosa Biofilm Development
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