Genomic islands ofPseudomonas aeruginosa

Abstract

Key to Pseudomonas aeruginosa’s ability to thrive in a diversity of niches is the presence of numerous genomic islands that confer adaptive traits upon individual strains. We reasoned that P. aeruginosa strains capable of surviving in the harsh environments of multiple hosts would therefore represent rich sources of genomic islands. To this end, we identified a strain, PSE9, that was highly virulent in both animals and plants. Subtractive hybridization was used to compare the genome of PSE9 to the less virulent strain PAO1. Nine genomic islands were identified in PSE9 that were absent in PAO1; seven of these had not been previously described. One these seven islands, designated PAGI-5, has already been shown to carry numerous interesting ORFs, including several required for virulence in mammals. Here we describe the remaining six genomic islands, PAGI-6, -7, -8, -9, -10, and -11, which include a prophage element and two Rhs elements.

Characterization of protease IV expression in Pseudomonas aeruginosa clinical isolates

“…Lee et al (2006) have reported pathogenicity-related genes, the presence or absence of which do not correlate directly with degree of virulence, suggesting virulence is more complex than simple autonomous functioning of virulence genes. Strain-variable virulence-associated genes have been reported within genomic islands of P. aeruginosa (Battle et al, 2009). These mobile genetic elements can contribute to virulence in a combinatorial manner with other accessory genome 'modules', resulting in strain-specific virulence (Lee et al, 2006).…”

Fatores envolvidos com a mobilização de PAPI-1

“…regulador transcricional dependente de zinco e uma proteína similar a TraY (fator acessório necessário para ligação da relaxase no plasmídeo F) de Cupriavidus metallidurans (Battle, et al 2009). …”

“…PAGI-9 e -10 são formadas por apenas um único gene cada, ambos relacionados a família Rhs que são elementos acessórios presente em E. coli, relacionada com biogênese do envelope celular e membrana externa, e PAGI-11 é uma região 28 de 2 kb que não contém nenhum gene predito e que não está presente em PSE9 e sim em PAO1 (McNulty, et al 2006;Battle, et al 2009). …”

“…São organismos com uma grande versatilidade metabólica e adaptativa sendo capazes de colonizar diversos ambientes (Lyczak, et al 2000). Pseudomonas stutzeri e requerido para oxidação de fosfito em fosfato (Battle, et al 2009). …”

“…Finally, in order to verify interactions involving the conserved proteins in PAPI-1 and XAC, two hybrid assays were carried out, but only false positives results were obtained. (Koonin, et al 2001;Mohd-Zain, et al 2004;Juhas, et al 2007;Mathee, et al 2008;Battle, et al 2009;Sentchilo, et al 2009 …”