Research Topic on Pseudomonas aeruginosa, Biology, Genetics, and Host–Pathogen Interactions

Abstract

Over the years, Pseudomonas aeruginosa has served as a paradigm for the study of gene expression, metabolism, and pathogenesis. The large genome, which approaches the complexity and size of lower eukaryotes, and an abundance of regulators, facilitates adaptation to almost any environment. During evolution, competition with other prokaryotes and the acquisition of defensive mechanisms to fend off eukaryotic predators have allowed the maintenance of antibiotic-resistance markers, degradative enzymes, and secretion systems, which impact upon human infection. Eleven articles, nine of which are comprehensive reviews, are presented to highlight these topics and provide an up-to-date resource. Genomes, Proteomes, Biology A perspective on the evolution of genomic diversity is provided in the initial article by Klockgether et al. (2011). The core genome of P. aeruginosa is highly conserved and collinearly arranged as a single chromosome. The mosaic structure of the genome is interrupted by the accessory genome being made up of regions of plasticity, integrated islands, transposons, phages, or IS-elements. Comparisons of strains from the same clonal complex, yet unrelated geographic origin, show a low substitution rate. Versatility is related to a combination of a large genome, accessory elements, and a variety of regulatory systems. Rao et al. (2011) use global proteomic approaches to study the differences between a mucoid and a non-mucoid isolate derived from the same patient. Data from mass spectrometry analyses utilizing isobaric tags and 2D-electrophoresis are correlated with microarray results to provide a snapshot of expression profiles. These techniques indicate that the type 6 secretion (T6S) and the mucoid phenotype are inversely correlated. Important technical considerations make this report a valuable resource for refinements of bacterial proteomics