In vitro identification of two adherence factors required for in vivo virulence of Pseudomonas fluorescens.

摘要: Abstract By enriching a random transposon insertion bank of Pseudomonas fluorescens for mutants affected in their adherence to the human extracellular matrix protein fibronectin, we isolated 23 adherence minus mutants. Mutants showed defect ability develop biofilm on an abiotic surface and were impaired virulence when tested vivo model fruit fly, Drosophila melanogaster . Molecular characterisation these that insertions localised two distinct chromosomal locations, which subsequently cloned characterised from A search databanks identified loci aeruginosa PAO1 genome with significant homology genes interrupted by insertions. Mutant IVC6 shows gmd , coding enzyme GDP-mannose dehydratase, involved synthesis A-band- O-antigen-containing lipopolysaccharide (LPS). IVG7 is significantly similar probable outer membrane strain PAO1, no specific function attributed thus far, yet Escherichia coli FadL, long-chain fatty acid transport. We propose this protein, together LPS, first steps P. leading host colonisation. Results presented here also demonstrate pathogenic potential assessed system, correlated its adhere fibronectin. Correlation between mutant phenotypes factors actual role discussed.