title: Transcriptome analyses and biofilm-forming characteristics of a clonal Pseudomonas aeruginosa from the cystic fibrosis lung.
abstract: Transmissible Pseudomonas aeruginosa clones potentially pose a serious threat to cystic fibrosis (CF) patients. The AES-1 clone has been found to infect up to 40 % of patients in five CF centres in eastern Australia. Studies were carried out on clonal and non-clonal (NC) isolates from chronically infected CF patients, and the reference strain PAO1, to gain insight into the properties of AES-1. The transcriptomes of AES-1 and NC isolates, and of PAO1, grown planktonically and as a 72 h biofilm were compared using PAO1 microarrays. Microarray data were validated using real-time PCR. Overall, most differentially expressed genes were downregulated. AES-1 differentially expressed bacteriophage genes, novel motility genes, and virulence and quorum-sensing-related genes, compared with both PAO1 and NC. AES-1 but not NC biofilms significantly downregulated aerobic respiration genes compared with planktonic growth, suggesting enhanced anaerobic/microaerophilic growth by AES-1. Biofilm measurement showed that AES-1 formed significantly larger and thicker biofilms than NC or PAO1 isolates. This may be related to expression of the gene PA0729, encoding a biofilm-enhancing bacteriophage, identified by PCR in all AES-1 but few NC isolates (n=42). Links with the Liverpool epidemic strain included the presence of PA0729 and the absence of the bacteriophage gene cluster PA0632-PA0639. No common markers were found with the Manchester strain. No particular differentially expressed gene in AES-1 could definitively be ascribed a role in its infectivity, thus increasing the likelihood that AES-1 infectivity is multi-factorial and possibly involves novel genes. This study extends our understanding of the transcriptomic and genetic differences between clonal and NC strains of P. aeruginosa from CF lung.
authors.affiliation: Department of Infectious Diseases and Immunology, University of Sydney, Sydney, Australia.
authors.forename: Jim
authors.initials: J
authors.lastname: Manos
authors.affiliation: Sydney Bioinformatics, University of Sydney, Sydney, Australia.|Department of Medicine, University of Sydney, Sydney, Australia.
authors.forename: Jonathan
authors.initials: J
authors.lastname: Arthur
authors.affiliation: Department of Infectious Diseases and Immunology, University of Sydney, Sydney, Australia.
authors.forename: Barbara
authors.initials: B
authors.lastname: Rose
authors.affiliation: Department of Infectious Diseases and Immunology, University of Sydney, Sydney, Australia.
authors.forename: Pholawat
authors.initials: P
authors.lastname: Tingpej
authors.affiliation: Department of Infectious Diseases and Immunology, University of Sydney, Sydney, Australia.
authors.forename: Carina
authors.initials: C
authors.lastname: Fung
authors.affiliation: Department of Infectious Diseases and Immunology, University of Sydney, Sydney, Australia.
authors.forename: Michelle
authors.initials: M
authors.lastname: Curtis
authors.affiliation: School of Biological Sciences, University of Southampton, Southampton, UK.|School of Biotechnology and Biomolecular Sciences, University of New South Wales, Sydney, Australia.
authors.forename: Jeremy S
authors.initials: JS
authors.lastname: Webb
authors.affiliation: Department of Infectious Diseases and Immunology, University of Sydney, Sydney, Australia.
authors.forename: Honghua
authors.initials: H
authors.lastname: Hu
authors.affiliation: School of Biotechnology and Biomolecular Sciences, University of New South Wales, Sydney, Australia.
authors.forename: Staffan
authors.initials: S
authors.lastname: Kjelleberg
authors.affiliation: A. W. Morrow Gastroenterology and Liver Centre, Centenary Institute of Cancer Medicine and Cell Biology, Royal Prince Alfred Hospital and Faculty of Medicine, University of Sydney, Sydney, Australia.
authors.forename: Mark D
authors.initials: MD
authors.lastname: Gorrell
authors.affiliation: Department of Respiratory Medicine, Royal Prince Alfred Hospital, Sydney, Australia.|Department of Medicine, University of Sydney, Sydney, Australia.
authors.forename: Peter
authors.initials: P
authors.lastname: Bye
authors.affiliation: Department of Infectious Diseases and Immunology, University of Sydney, Sydney, Australia.
authors.forename: Colin
authors.initials: C
authors.lastname: Harbour
mesh_terms: D000328:Adult; D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism*; D018441:Biofilms / Q000254:growth & development*; D002908:Chronic Disease; D003550:Cystic Fibrosis / Q000382:microbiology*; D005260:Female; D020869:Gene Expression Profiling; D015964:Gene Expression Regulation, Bacterial; D006801:Humans; D008168:Lung / Q000382:microbiology*; D008297:Male; D020411:Oligonucleotide Array Sequence Analysis; D011552:Pseudomonas Infections / Q000382:microbiology; D011550:Pseudomonas aeruginosa / Q000235:genetics / Q000254:growth & development* / Q000302:isolation & purification / Q000378:metabolism; D053038:Quorum Sensing; D055815:Young Adult
chemical_list: D001426:Bacterial Proteins