Does the mode of dispersion determine the properties of dispersed Pseudomonas aeruginosa biofilm cells?

Introduction: Actively dispersed Pseudomonas aeruginosa biofilm cells differ from planktonic cells, as they have a lower intracellular cyclic di-guanosine monophosphate (c-di-GMP) concentration and show increased virulence. In addition, the nature of the dispersion trigger has been shown to influence the antibiotic susceptibility of dispersed cells. However, properties of passively-dispersed cells, in which the dispersion trigger directly releases cells from the biofilm, have not been described.

The role of small proteins in J2315 biofilm formation, persistence and intracellular growth.

infections are difficult to treat due to resistance, biofilm formation and persistence. strain J2315 has a large multi-replicon genome (8.06 Mb) and the function of a large fraction of (conserved) hypothetical genes remains elusive.

Exploring Light-Sensitive Nanocarriers for Simultaneous Triggered Antibiotic Release and Disruption of Biofilms Upon Generation of Laser-Induced Vapor Nanobubbles.

Impaired penetration of antibiotics through bacterial biofilms is one of the reasons for failure of antimicrobial therapy. Hindered drug diffusion is caused on the one hand by interactions with the sticky biofilm matrix and on the other hand by the fact that bacterial cells are organized in densely packed clusters of cells. Binding interactions with the biofilm matrix can be avoided by encapsulating the antibiotics into nanocarriers, while interfering with the integrity of the dense cell clusters can enhance drug transport deep into the biofilm.

Repeated photoporation with graphene quantum dots enables homogeneous labeling of live cells with extrinsic markers for fluorescence microscopy.

In the replacement of genetic probes, there is increasing interest in labeling living cells with high-quality extrinsic labels, which avoid over-expression artifacts and are available in a wide spectral range. This calls for a broadly applicable technology that can deliver such labels unambiguously to the cytosol of living cells. Here, we demonstrate that nanoparticle-sensitized photoporation can be used to this end as an emerging intracellular delivery technique.

Laser-induced vapour nanobubbles improve drug diffusion and efficiency in bacterial biofilms.

Hindered penetration of antibiotics through biofilms is one of the reasons for the alarming increase in bacterial tolerance to antibiotics. Here, we investigate the potential of laser-induced vapour nanobubbles (VNBs) formed around plasmonic nanoparticles to locally disturb biofilm integrity and improve antibiotics diffusion. Our results show that biofilms of both Gram-negative (Burkholderia multivorans, Pseudomonas aeruginosa) and Gram-positive (Staphylococcus aureus) bacteria can be loaded with cationic 70-nm gold nanoparticles and that subsequent laser illumination results in VNB formation inside the biofilms.