Unraveling the immunopotentiation of P. aeruginosa PAPI-1 encoded pilin: From immunoinformatics survey to active immunization

Antimicrobial Potential of Chitosan Films Incorporated with Alcoholic Extract from Mimosa tenuiflora Leaves

Antimicrobial films were prepared with chitosan containing the methanolic extract of M. tenuiflora leaves (FECT20 %, FECT30 %, and FECT40 %), and their antimicrobial activities were evaluated by agar diffusion. The films were characterized by IR spectroscopy, scanning electron microscopy (SEM) and TG/DTG curves. TG/DTG curves showed thermal stability of chitosan-extract films up to 166 °C. Micrographs of chitosan-extract films revealed an increase in porosity with the addition of extract. The FECT40 % film showed inhibition zone diameters (IZ) against Micrococcus luteus, Staphylococcus aureus, Bacillus subtilis, and B. cereus, ranging from 1.0±0.02 to 0.72±0.09 cm. Only FECT30 % and FECT40 % inhibited the P. aeruginosa with IZs of 0.68±0.02 and 0.77±0.06 cm, respectively. In turn, the extract showed inhibition against B. subtilis and B. cereus, with IZs values of 0.92±0.2 cm and 0.72±0.05 cm, respectively. Additionally, the crude extract presented antioxidant potential with inhibition percentages of 32.74 %±0.90 for ABTS and 27.04 %±1.36 for DPPH. The antimicrobial and antioxidant activities of the crude extract, as well as the antimicrobial property of chitosan-extract films, suggests the potential of these biopolymers for the development of wound healing bandages and new food packaging alternatives.

Pseudomonas aeruginosa Vaccine Development: Lessons, Challenges, and Future Innovations

Pseudomonas aeruginosa is an opportunistic pathogen with a multidrug-resistant profile that has become a critical threat to global public health. It is one of the main causes of severe nosocomial infections, including ventilator-associated pneumonia, chronic infections in patients with cystic fibrosis, and bloodstream infections in immunosuppressed individuals. Development of vaccines against P. aeruginosa is a major challenge owing to the high capacity of this bacterium to form biofilms, its wide arsenal of virulence factors (including secretion systems, lipopolysaccharides, and outer membrane proteins), and its ability to evade the host immune system. This review provides a comprehensive historical overview of vaccine development efforts targeting this pathogen, ranging from early attempts in the 1970s to recent advancements, including vaccines based on novel proteins and emerging technologies such as nanoparticles and synthetic conjugates. Despite numerous promising preclinical developments, very few candidates have progressed to clinical trials, and none have achieved final approval. This panorama highlights the significant scientific efforts undertaken and the inherent complexity of successfully developing an effective vaccine against P. aeruginosa.