title: Pseudomonas aeruginosa population structure revisited under environmental focus: impact of water quality and phage pressure.
abstract: Pseudomonas aeruginosa attracts research attention as a common opportunistic nosocomial pathogen causing severe health problems in humans. Nevertheless, its primary habitat is the natural environment. Here, we relate the genetic diversity of 381 environmental isolates from rivers in northern Germany to ecological factors such as river system, season of sampling and different levels of water quality. From representatives of 99 environmental clones, also in comparison with 91 clinical isolates, we determined motility phenotypes, virulence factors, biofilm formation, serotype and the resistance to seven environmental P.aeruginosa phages. The integration of genetic, ecological and phenotypic data showed (i) the presence of several extended clonal complexes (ecc) which are non-uniformly distributed across different water qualities, and (ii) a correlation of the hosts' serotype composition with susceptibility towards distinct groups of environmental phages. For at least one ecc (eccB), we assumed the ecophysiological differences on environmental water adaptation and phage resistance to be so distinct as to reinforce an environmentally driven cladogenic split from the remainder of P.aeruginosa. In summary, we conclude that the majority of the microevolutionary population dynamics of P.aeruginosa were shaped by the natural environment and not by the clinical habitat.
authors.affiliation: HZI, Helmholtz Centre for Infection Research, Inhoffenstr. 7, 38124 Braunschweig.
authors.forename: Katherina
authors.initials: K
authors.lastname: Selezska
authors.forename: Marlon
authors.initials: M
authors.lastname: Kazmierczak
authors.forename: Mathias
authors.initials: M
authors.lastname: Müsken
authors.forename: Julia
authors.initials: J
authors.lastname: Garbe
authors.forename: Max
authors.initials: M
authors.lastname: Schobert
authors.forename: Susanne
authors.initials: S
authors.lastname: Häussler
authors.forename: Lutz
authors.initials: L
authors.lastname: Wiehlmann
authors.forename: Christine
authors.initials: C
authors.lastname: Rohde
authors.forename: Johannes
authors.initials: J
authors.lastname: Sikorski
mesh_terms: D001435:Bacteriophages / Q000502:physiology*; D018441:Biofilms; D014644:Genetic Variation; D005858:Germany; D006801:Humans; D010641:Phenotype; D011552:Pseudomonas Infections / Q000382:microbiology; D011550:Pseudomonas aeruginosa / Q000235:genetics / Q000502:physiology* / Q000821:virology*; D045483:Rivers / Q000382:microbiology; D012703:Serotyping; D016019:Survival Analysis; D014871:Water Microbiology; D060753:Water Quality