New strategies to combat bacterial infections

Group: Bacterial infections: antimicrobial therapies
Group leader: Eduard Torrents (etorrents@ibecbarcelona.eu)

Infectious diseases are the leading cause of death worldwide. Disease-causing bacteria that resist antibiotic treatment are now widespread in every part of the world and have reached “alarming levels” in many areas, as stated by the World Health Organization. “The problem is so serious that it threatens the achievements of modern medicine,” entering to A post-antibiotic era in which common infections and minor injuries can kill. Nowadays, bacterial biofilm-based infections have emerged as a significant public health concern.

We aim to explore and characterize new antimicrobial molecules that specifically inhibit new antibacterial targets. Also, we are exploring new antimicrobial strategies based on nanoparticles to deliver new and pre-existing antimicrobials with the capacity to evade the immune system and able to penetrate formed bacterial biofilms. The group is focused on the study of mixed biofilms and study the interaction between two different bacteria. Fundamental studies in microbial physiology, new vaccines, molecular microbiology and microfluidics applied to the microbiology diagnostic are also performed in our laboratory. See further details and publications at our group web page: www.torrentslab.eu.

Fig 1: Left: Surface plot
analysis of Pseudomonas aeruginosa wild type PAO1 four-day old biofilm. Close images
of the biofilm under the confocal scanning laser microscopy. It is shown
a representation of the nanoparticles used in this study.

Fig 2: Detailed microscopy observations of structured biofilms from P. aeruginosa PAO1 wild- type and different ribonucleotide reductase mutants. On the left, a scheme of the longitudinal structure
of P. aeruginosa biofilm is represented, labelled with indications of the oxygen concentration along the biofilm. On the right, images taken from the aerobic region of the biofilm (top part, superficial biofilm) and from the anaerobic region (bottom part, deeper in the biofilm structure) are shown.

Fig 3: Role of NrdDG in infection. Fluorescence intensity values of individual embryos infected with different P. aeruginosa strains (PAO1 and
PA14) containing the pETS136-C and pETS196-T vectors over 24 h post-infection.

Fig. 4. Balanced and stable Pseudomonas aeruginosa PA14 and Staphylococcus aureus Newman strain populations within a three-day-old mixed biofilm grown in continuous flow.