title: Swarming motility, secretion of type 3 effectors and biofilm formation phenotypes exhibited within a large cohort of Pseudomonas aeruginosa clinical isolates.
abstract: Pseudomonas aeruginosa is an opportunistic Gram-negative pathogen capable of acutely infecting or persistently colonizing susceptible hosts. P. aeruginosa colonizes surfaces in vitro by either biofilm formation or swarming motility. The choice of behaviour is influenced by the physical properties of the surface and specific nutrient availability, and subject to regulatory networks that also govern type 2 and type 3 protein secretion. Biofilm formation by clinical isolates has been well-studied. However, the swarming behaviour of human isolates has not been extensively analysed. We collected isolates from 237 hospitalized patients without cystic fibrosis and analysed motility and secretion phenotypes of each isolate. We found biofilm formation and swarming to be negatively associated, while swarming was positively associated with the secretion of both proteases and type 3 exoenzymes. Most isolates were capable of type 3 secretion and biofilm formation, even though these traits are considered to favour distinct modes of pathogenesis. Our data demonstrate that while clinical isolates display diverse motility, biofilm and secretion phenotypes, many of the predicted relationships between swarming motility and other phenotypes observed in laboratory strains also hold true for bacteria isolated from human patients.
authors.affiliation: Department of Pediatrics and Laboratory Medicine (Infectious Diseases and Clinical Microbiology), Yale University School of Medicine, New Haven, CT 06520, USA.
authors.forename: Thomas S
authors.initials: TS
authors.lastname: Murray
authors.affiliation: L2 Diagnostics, New Haven, CT 06511, USA.
authors.forename: Michel
authors.initials: M
authors.lastname: Ledizet
authors.affiliation: Section of Microbial Pathogenesis, Yale University School of Medicine, New Haven, CT 06520, USA.|Department of Medicine (Infectious Diseases), Yale University School of Medicine, New Haven, CT 06520, USA.
authors.forename: Barbara I
authors.initials: BI
authors.lastname: Kazmierczak
mesh_terms: D000293:Adolescent; D000328:Adult; D001426:Bacterial Proteins / Q000378:metabolism*; D018441:Biofilms / Q000254:growth & development*; D002648:Child; D002675:Child, Preschool; D006760:Hospitalization; D006801:Humans; D008124:Locomotion; D026901:Membrane Transport Proteins / Q000378:metabolism*; D011552:Pseudomonas Infections / Q000382:microbiology*; D011550:Pseudomonas aeruginosa / Q000302:isolation & purification* / Q000502:physiology*; D037521:Virulence Factors / Q000378:metabolism*; D055815:Young Adult
chemical_list: D001426:Bacterial Proteins; D026901:Membrane Transport Proteins; D037521:Virulence Factors