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O serotype-independent susceptibility of Pseudomonas aeruginosa to lectin-like pyocins.

Ghequire MG, Dingemans J, Pirnay JP, De Vos D, Cornelis P, De Mot R - Microbiologyopen (2014)

Bottom Line: The recombinant proteins exhibit species-specific antagonistic activities down to nanomolar concentrations against clinical and environmental P. aeruginosa strains, including several multidrug-resistant isolates.No correlation was found between L pyocin susceptibility and phylogenetic relatedness of P. aeruginosa isolates.Sensitive strains were retrieved in 13 out of 15 O serotypes tested, excluding the possibility that the highly variable and immunogenic O serotype antigen of the LPS coating would represent a dominant susceptibility-discriminating factor.

View Article: PubMed Central - PubMed

Affiliation: Centre of Microbial and Plant Genetics, University of Leuven, 3001, Heverlee, Belgium.

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Functional diversity of L pyocins. Tree representation inferred from the similarity matrix of a composite data set of 328 Pseudomonas aeruginosa strains, marking L pyocin susceptibility (A) and distribution of O serotypes (B). The respective color legends specify pyocin susceptibility (A) and O serotype (B). White dots represent untested (A) or untypable strains (B). Circles correspond to a polyphasic profile and are scaled with an increasing number of member representatives. Line color and style represent branch lengths. A decreasing phylogenetic relatedness corresponds to a gradual decline in line style, from solid to dashed and color change, from black to gray, respectively. The grouping of the resulting averaged composite similarity matrix was achieved by standard MST analysis, with single and double locus variable priority rules. Priority standards were as follows: identification policy, all taxa with zero inter-taxon distance were identified; priority rule 1, maximum number of N-locus variants (N = 1) with weight 10000; priority rule 2, maximum number of N-locus variants (N = 2) with weight 10. Branch length scaling is logarithmic. Line color and style represent branch lengths: lengths up to 1, thickness 2 and solid; lengths up to 3, thickness 1 and solid; lengths up to 4, thickness 1 and dashed; lengths above 4, thickness 1 and dotted. Line color changes gradually from black (up to 1) to light gray (above 4).
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fig06: Functional diversity of L pyocins. Tree representation inferred from the similarity matrix of a composite data set of 328 Pseudomonas aeruginosa strains, marking L pyocin susceptibility (A) and distribution of O serotypes (B). The respective color legends specify pyocin susceptibility (A) and O serotype (B). White dots represent untested (A) or untypable strains (B). Circles correspond to a polyphasic profile and are scaled with an increasing number of member representatives. Line color and style represent branch lengths. A decreasing phylogenetic relatedness corresponds to a gradual decline in line style, from solid to dashed and color change, from black to gray, respectively. The grouping of the resulting averaged composite similarity matrix was achieved by standard MST analysis, with single and double locus variable priority rules. Priority standards were as follows: identification policy, all taxa with zero inter-taxon distance were identified; priority rule 1, maximum number of N-locus variants (N = 1) with weight 10000; priority rule 2, maximum number of N-locus variants (N = 2) with weight 10. Branch length scaling is logarithmic. Line color and style represent branch lengths: lengths up to 1, thickness 2 and solid; lengths up to 3, thickness 1 and solid; lengths up to 4, thickness 1 and dashed; lengths above 4, thickness 1 and dotted. Line color changes gradually from black (up to 1) to light gray (above 4).

Mentions: Seventy strains in the test panel were selected from a collection of 328 P. aeruginosa isolates, based on their distribution across a MST previously built from a polyphasic data set (Pirnay et al. 2009). Characteristics include O serotype, fluorescent amplified-fragment length polymorphism pattern, gene sequences of outer membrane proteins (oprI, oprL, and oprD), pyoverdine receptors (fpvA and fpvB), group I pilin glycosyltransferase (tfpO), and the prevalence of exoenzyme genes (exoS and exoU). Patterns of pyocin sensitivity did not correlate with any of these characteristics, as variation occurred even within clonal complexes (Fig. 6A). Susceptible strains were found in virtually all MST clusters and, hence, liability to pyocin L-mediated killing cannot be attributed to phylogenetic relatedness, suggesting that (a) highly variable epitope(s) mainly determine(s) strain victimization.


O serotype-independent susceptibility of Pseudomonas aeruginosa to lectin-like pyocins.

Ghequire MG, Dingemans J, Pirnay JP, De Vos D, Cornelis P, De Mot R - Microbiologyopen (2014)

Functional diversity of L pyocins. Tree representation inferred from the similarity matrix of a composite data set of 328 Pseudomonas aeruginosa strains, marking L pyocin susceptibility (A) and distribution of O serotypes (B). The respective color legends specify pyocin susceptibility (A) and O serotype (B). White dots represent untested (A) or untypable strains (B). Circles correspond to a polyphasic profile and are scaled with an increasing number of member representatives. Line color and style represent branch lengths. A decreasing phylogenetic relatedness corresponds to a gradual decline in line style, from solid to dashed and color change, from black to gray, respectively. The grouping of the resulting averaged composite similarity matrix was achieved by standard MST analysis, with single and double locus variable priority rules. Priority standards were as follows: identification policy, all taxa with zero inter-taxon distance were identified; priority rule 1, maximum number of N-locus variants (N = 1) with weight 10000; priority rule 2, maximum number of N-locus variants (N = 2) with weight 10. Branch length scaling is logarithmic. Line color and style represent branch lengths: lengths up to 1, thickness 2 and solid; lengths up to 3, thickness 1 and solid; lengths up to 4, thickness 1 and dashed; lengths above 4, thickness 1 and dotted. Line color changes gradually from black (up to 1) to light gray (above 4).
© Copyright Policy - open-access
Related In: Results  -  Collection

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fig06: Functional diversity of L pyocins. Tree representation inferred from the similarity matrix of a composite data set of 328 Pseudomonas aeruginosa strains, marking L pyocin susceptibility (A) and distribution of O serotypes (B). The respective color legends specify pyocin susceptibility (A) and O serotype (B). White dots represent untested (A) or untypable strains (B). Circles correspond to a polyphasic profile and are scaled with an increasing number of member representatives. Line color and style represent branch lengths. A decreasing phylogenetic relatedness corresponds to a gradual decline in line style, from solid to dashed and color change, from black to gray, respectively. The grouping of the resulting averaged composite similarity matrix was achieved by standard MST analysis, with single and double locus variable priority rules. Priority standards were as follows: identification policy, all taxa with zero inter-taxon distance were identified; priority rule 1, maximum number of N-locus variants (N = 1) with weight 10000; priority rule 2, maximum number of N-locus variants (N = 2) with weight 10. Branch length scaling is logarithmic. Line color and style represent branch lengths: lengths up to 1, thickness 2 and solid; lengths up to 3, thickness 1 and solid; lengths up to 4, thickness 1 and dashed; lengths above 4, thickness 1 and dotted. Line color changes gradually from black (up to 1) to light gray (above 4).
Mentions: Seventy strains in the test panel were selected from a collection of 328 P. aeruginosa isolates, based on their distribution across a MST previously built from a polyphasic data set (Pirnay et al. 2009). Characteristics include O serotype, fluorescent amplified-fragment length polymorphism pattern, gene sequences of outer membrane proteins (oprI, oprL, and oprD), pyoverdine receptors (fpvA and fpvB), group I pilin glycosyltransferase (tfpO), and the prevalence of exoenzyme genes (exoS and exoU). Patterns of pyocin sensitivity did not correlate with any of these characteristics, as variation occurred even within clonal complexes (Fig. 6A). Susceptible strains were found in virtually all MST clusters and, hence, liability to pyocin L-mediated killing cannot be attributed to phylogenetic relatedness, suggesting that (a) highly variable epitope(s) mainly determine(s) strain victimization.

Bottom Line: The recombinant proteins exhibit species-specific antagonistic activities down to nanomolar concentrations against clinical and environmental P. aeruginosa strains, including several multidrug-resistant isolates.No correlation was found between L pyocin susceptibility and phylogenetic relatedness of P. aeruginosa isolates.Sensitive strains were retrieved in 13 out of 15 O serotypes tested, excluding the possibility that the highly variable and immunogenic O serotype antigen of the LPS coating would represent a dominant susceptibility-discriminating factor.

View Article: PubMed Central - PubMed

Affiliation: Centre of Microbial and Plant Genetics, University of Leuven, 3001, Heverlee, Belgium.

Show MeSH
Related in: MedlinePlus