Chapters authored
Pharmaceutical Antibiotics at a Significant Level in Nature: From Hospitals, Livestock, and Plants to Soil, Water, and Sea
Antibiotics were the world’s great therapeutic hope after the Second World War, but today, unmonitored use has become one of the greatest risks for humanity. Without overestimation, one of the last scientific books on antibiotics was entitled: Antibiotics, the perfect storm. Before to environmental contamination by antibiotics, the pathogens got resistant to them. Because of the radical changes that antibiotics have brought about, they can generate new resistant bacteria in the environment that were previously harmless. These microorganisms will be exposed to concentrations of antibiotics never reached or will be exposed to unknown molecules that, for many of them, in certain environments, have never been exposed before. Initially, many of these antibiotics did not penetrate soils with high agricultural production, but in the following decades, they were even interspersed into crops. Nowadays, hundreds of tons of antibiotics are dumped into rivers and the sea. Many hospitals have water treatment facilities to prevent significant contamination, but not all companies, farms, and hospitals in developed, emerging, or poor countries apply wastewater treatment. Antibiotics are incorporated into wild microorganisms and plants, triggering a broad “unnatural” resistance, which will rapidly incorporate this information into the genome of other pathogenic microorganisms by horizontal transfer. On the other hand, antibiotics could be incorporated into drinking water and water intended for human or agricultural consumption that travels without being detected or monitored. This review covers the most important aspects of environmental pollution by antibiotics.
Part of the book: Emerging Contaminants
The Pangenome of Pseudomonas aeruginosa
This review summarizes the most important reports about Pseudomonas aeruginosa pangenome. Pan-genomics has tackled some fundamental concerns in pathogenic bacteria. PATRIC and other databases, store more than 9000 P. aeruginosa genomes. This data mining is an opportunity to develop discoveries related to antibiotic resistance, virulence, pathogenicity, fitness, and evolution, among others. Observing the different pangenomes of P. aeruginosa, it is concluded that this species has an open pangenome, and its accessory genome is larger than the central genome. HGT is one important source for P. aeruginosa genome. In recent years various authors developed P. aeruginosa pangenomes, from works with five genomes to more than 1300 genomes. This last work analyzed 54,272 genes, and they found a short and tiny core genome (only 665 genes). Other research with lesser strains or genomes identified a core genome bigger, almost 20% of the pangenome. Nevertheless, the total work proves that the accessory plus unique genome is larger than the core genome in P. aeruginosa.
Part of the book: Pseudomonas aeruginosa