Pseudomonas aeruginosa causes chronic lung infections in people with cystic fibrosis (CF) and acute opportunistic infections in people without CF. Forty-two P. aeruginosa strains from a range of clinical and environmental sources were collated into a single reference strain panel to harmonise research on this diverse opportunistic pathogen. To facilitate further harmonized and comparable research on P. aeruginosa, we characterized the panel strains for growth rates, motility, virulence in the Galleria mellonella infection model, pyocyanin and alginate production, mucoid phenotype, LPS pattern, biofilm formation, urease activity, and antimicrobial and phage susceptibilities. Phenotypic diversity across the P. aeruginosa panel was apparent for all phenotypes examined, agreeing with the marked variability seen in this species. However, except for growth rate, the phenotypic diversity among strains from CF versus non-CF sources was comparable. CF strains were less virulent in the G. mellonella model than non-CF strains (P50.037). Transmissible CF strains generally lacked O-antigen, produced less pyocyanin and had low virulence in G. mellonella. Furthermore, in the three sets of sequential CF strains,

Intensive exploitation, poor recycling, low repeatable use, and unusual resistance of plastics to environmental and microbiological action result in accumulation of huge waste amounts in terrestrial and marine environments, causing enormous hazard for human and animal life. In the last decades, much scientific interest has been focused on plastic biodegradation. Due to the comparatively short evolutionary period of their appearance in nature, sufficiently effective enzymes for their biodegradation are not available. Plastics are designed for use in conditions typical for human activity, and their physicochemical properties roughly change at extreme environmental parameters like low temperatures, salt, or low or high pH that are typical for the life of extremophilic microorganisms and the activity of their enzymes. This review represents a first attempt to summarize the extraordinarily limited information on biodegradation of conventional synthetic plastics by thermophilic, alkaliphilic, halophilic, and psychrophilic bacteria in natural environments and laboratory conditions. Most of the available data was reported in the last several years and concerns moderate extremophiles. Two main questions are highlighted in it: which extremophilic bacteria and their enzymes are reported to be involved in the degradation of different synthetic plastics, and what could be the impact of extremophiles in future technologies for resolving of pollution problems.

Contamination of surfaces in hospitals and food industry by bacterial biofilms is a serious health risk. Of concern is their resistance to routine antibacterials and disinfectants. This requires the development of novel approaches to biofilm detachment. The study evaluates the effectiveness of cationic polymer micelles (CPMs) against pre‐formed biofilms. CPMs based on different polycations were used. The hydrodynamic radius of the particles ranged from 16 to 360 nm. Biofilms of Escherichia coli 420, Pseudomonas aeruginosa PAO1, Staphylococcus aureus 29213 and Bacillus subtilis 168 were cultivated for 24 h then the pre‐formed biofilms were treated with the CPMs for 2, 4 or 6 h. Biofilm biomass was evaluated by the crystal violet assay, and live/dead fluorescence test was applied for bacterial viability. The ability of CPMs to interact with pre‐formed biofilms of the model strains was evaluated. We observed that the most effective CPMs were those based on poly(2‐(dimethylamino)ethyl methacrylate) copolymers which reduced the biofilm biomass three‐ to four‐fold compared with the treatment of the biofilm with water. Significantly reduced vitality of the bacteria in the biofilms was registered by the live/dead stain. The results indicate the applicability of the CPMs for disinfection of biofilm‐contaminated surfaces and the treatment of wounds.

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