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Jeanmarie Meyer - One of the best experts on this subject based on the ideXlab platform.
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Pyoverdine and histicorrugatin-mediated iron acquisition in Pseudomonas thivervalensis.
Biometals : an international journal on the role of metal ions in biology biochemistry and medicine, 2016Co-Authors: Sandra Matthijs, Jeanmarie Meyer, Nathalie Brandt, Marc Ongena, Wafa Achouak, Herbert BudzikiewiczAbstract:The genome of Pseudomonas thivervalensis LMG 21626(T) has been sequenced and a genomic, genetic and structural analysis of the siderophore mediated iron acquisition was undertaken. Pseudomonas thivervalensis produces two structurally new siderophores, Pyoverdine PYOthi which is typical for P. thivervalensis strains and a closely related strain, and the lipopeptidic siderophore histicorrugatin which is also detected in P. lini. Histicorrugatin consists out of an eight amino acid long peptide which is linked to octanoic acid. It is structurally related to the siderophores corrugatin and ornicorrugatin. Analysis of the proteome for TonB-dependent receptors identified 25 candidates. Comparison of the TonB-dependent receptors of P. thivervalensis with the 17 receptors of its phylogenetic neighbor, P. brassicacearum subsp. brassicacearum NFM 421, showed that NFM 421 shares the same set of receptors with LMG 21626(T), including the histicorrugatin receptor. An exception was found for their cognate Pyoverdine receptor which can be explained by the observation that both strains produce structurally different Pyoverdines. Mass analysis showed that NFM 421 did not produce histicorrugatin, but the analogue ornicorrugatin. Growth stimulation assays with a variety of structurally distinct Pyoverdines produced by other Pseudomonas species demonstrated that LMG 21626(T) and NFM 421 are able to utilize almost the same set of Pyoverdines. Strain NFM 421 is able utilize two additional Pyoverdines, Pyoverdine of P. fluorescens Pf0-1 and P. citronellolis LMG 18378(T), these Pyoverdines are probably taken up by the FpvA receptor of NFM 421.
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Pyoverdine Siderophores as Taxonomic and Phylogenic Markers
Pseudomonas, 2010Co-Authors: Jeanmarie MeyerAbstract:A total of 638 fluorescent Pseudomonas strains, representing 64 different species, have been analyzed through siderotyping. Altogether, the data allow considering Pyoverdine, the fluorescent pigment and siderophore, which characterizes these species, as a very powerful taxonomic marker. Pyoverdine characterization through isoelectrophoresis and iron transport capacity allows an easy and rapid identification at the species level of most strains without the need of any other phenotypic or genomic identification tests. Moreover, the comparison of the 63 Pyoverdine molecular structures, which are presently fully determined, allows the identification of groups of structurally closely related Pyoverdines, which producer strains correspond to highly phylogenetically related strains. Thus, Pyoverdines, as taxonomic as well as phylogenic markers, are molecules of great importance for the characterization and a better knowledge of the fluorescent Pseudomonas.
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Pseudomonas cedrina subsp. fulgida subsp. nov., a fluorescent bacterium isolated from the phyllosphere of grasses; emended description of Pseudomonas cedrina and description of Pseudomonas cedrina subsp. cedrina subsp. nov.
International Journal of Systematic and Evolutionary Microbiology, 2009Co-Authors: Undine Behrendt, Jeanmarie Meyer, Peter Schumann, Andreas UlrichAbstract:The taxonomic position of a group of four strains, isolated from the phyllosphere of grasses, within the species Pseudomonas cedrina was investigated. The isolates formed a separate cluster through ribotyping and MALDI-TOF MS, which could be clearly differentiated from the type strain of P. cedrina. The differences found between the patterns of the type strain of P. cedrina and the novel isolates were more distinct than those between the type strain and recognized species of the genus Pseudomonas, which were phylogenetically related by 16S rRNA gene sequence analysis. Physiological characterization also revealed significant differences between the novel grass isolates and the type strain of P. cedrina. Siderotyping of the Pyoverdines revealed identical Pyoverdine-isoelectrofocusing patterns for the novel isolates and the type strain of P. cedrina. However, Pyoverdine-mediated (59)Fe cross uptake studies indicated differences in the siderotype. In contrast, phylogenetic analysis based on 16S rRNA gene sequence analysis and DNA-DNA hybridization studies (reassociation value 76.4 %) supported the affiliation of the novel isolates to the species P. cedrina. As a consequence of these observations, the splitting of the species P. cedrina into two novel subspecies Pseudomonas cedrina subsp. cedrina subsp. nov. (type strain CFML 96-198(T)=CIP 105541(T)=DSM 17516(T)) and Pseudomonas cedrina subsp. fulgida subsp. nov. (type strain P 515/12(T)=DSM 14938(T)=LMG 21467(T)) is proposed.
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Siderophore-mediated iron acquisition in the entomopathogenic bacterium Pseudomonas entomophila L48 and its close relative Pseudomonas putida KT2440.
BioMetals, 2009Co-Authors: Sandra Matthijs, Jeanmarie Meyer, Herbert Budzikiewicz, Georges Laus, Kourosch Abbaspour-tehrani, Mathias Schäfer, Pierre CornelisAbstract:Pseudomonas entomophila L48 is a recently identified entomopathogenic bacterium which, upon ingestion, kills Drosophila melanogaster, and is closely related to P. putida. The complete genome of this species has been sequenced and therefore a genomic, genetic and structural analysis of the siderophore-mediated iron acquisition was undertaken. P. entomophila produces two siderophores, a structurally new and unique Pyoverdine and the secondary siderophore pseudomonine, already described in P. fluorescens species. Structural analysis of the Pyoverdine produced by the closely related P. putida KT2440 showed that this strain produces an already characterised Pyoverdine, but different from P. entomophila, and no evidence was found for the production of a second siderophore. Growth stimulation assays with heterologous Pyoverdines demonstrated that P. entomophila is able to utilize a large variety of structurally distinct Pyoverdines produced by other Pseudomonas species. In contrast, P. putida KT2440 is able to utilize only its own Pyoverdine and the Pyoverdine produced by P. syringae LMG 1247. Our data suggest that although closely related, P. entomophila is a more efficient competitor for iron than P. putida.
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Fpva Bound to Non-Cognate Pyoverdines: Molecular Basis of Siderophore Recognition by an Iron Transporter.
Molecular microbiology, 2009Co-Authors: Jason Greenwald, Jeanmarie Meyer, Christelle Gruffaz, Isabelle J. Schalk, Mirella Nader, Hervé Celia, Valérie A. Geoffroy, Franc PattusAbstract:Summary The first step in the specific uptake of iron via sidero- phores in Gram-negative bacteria is the recognition and binding of a ferric siderophore by its cognate receptor. We investigated the molecular basis of this event through structural and biochemical approaches. FpvA, the Pyoverdine-Fe transporter from Pseudomonas aeruginosa ATCC 15692 (PAO1 strain), is able to transport ferric-Pyoverdines origi- nating from other species, whereas most fluorescent pseudomonads are only able to use the one they produce among the more than 100 known different Pyoverdines. We solved the structure of FpvA bound to non-cognate Pyoverdines of high- or low-affinity and found a close correlation between receptor- ligand structure and the measured affinities. The structure of the first amino acid residues of the Pyoverdine chain distinguished the high- and low- affinity binders while the C-terminal portion of the Pyoverdines, often cyclic, does not appear to contribute extensively to the interaction between the siderophore and its transporter. The specificity of the ferric-Pyoverdine binding site of FpvA is con- ferred by the structural elements common to all ferric-Pyoverdines, i.e. the chromophore, iron, and its chelating groups.
K Poole - One of the best experts on this subject based on the ideXlab platform.
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FpvA-mediated ferric Pyoverdine uptake in Pseudomonas aeruginosa: identification of aromatic residues in FpvA implicated in ferric Pyoverdine binding and transport.
Journal of bacteriology, 2005Co-Authors: Jiang-sheng Shen, Jeanmarie Meyer, Valerie Geoffroy, S Neshat, Allison Meldrum, Zongchao Jia, K PooleAbstract:A number of aromatic residues were seen to cluster in the upper portion of the three-dimensional structure of the FpvA ferric Pyoverdine receptor of Pseudomonas aeruginosa, reminiscent of the aromatic binding pocket for ferrichrome in the FhuA receptor of Escherichia coli. Alanine substitutions in three of these, W362, W391, and F795, markedly compromised ferric Pyoverdine binding and transport, consistent with a role of FpvA in ferric Pyoverdine recognition.
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FpvA Receptor Involvement in Pyoverdine Biosynthesis in Pseudomonas aeruginosa
Journal of bacteriology, 2002Co-Authors: Jiang-sheng Shen, Allison Meldrum, K PooleAbstract:Alignment of the Pseudomonas aeruginosa ferric Pyoverdine receptor, FpvA, with similar ferric-siderophore receptors revealed that the mature protein carries an extension of ca. 70 amino acids at its N terminus, an extension shared by the ferric pseudobactin receptors of P. putida. Deletion of fpvA from the chromosome of P. aeruginosa reduced Pyoverdine production in this organism, as a result of a decline in expression of genes (e.g., pvdD) associated with the biosynthesis of the Pyoverdine peptide moiety. Wild-type fpvA restored pvd expression in the mutant, thereby complementing its Pyoverdine deficiency, although a deletion derivative of fpvA encoding a receptor lacking the N terminus of the mature protein did not. The truncated receptor was, however, functional in Pyoverdine-mediated iron uptake, as evidenced by its ability to promote Pyoverdine-dependent growth in an iron-restricted medium. These data are consistent with the idea that the N-terminal extension plays a role in FpvA-mediated Pyoverdine biosynthesis in P. aeruginosa.
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The pvc gene cluster of Pseudomonas aeruginosa: role in synthesis of the Pyoverdine chromophore and regulation by PtxR and PvdS.
Journal of bacteriology, 1999Co-Authors: Alain Stintzi, Jeanmarie Meyer, Urs A. Ochsner, Zaiga Johnson, Martin J. Stonehouse, Michael L. Vasil, K PooleAbstract:A putative operon of four genes implicated in the synthesis of the chromophore moiety of the Pseudomonas aeruginosa siderophore Pyoverdine, dubbed pvcABCD (where pvc stands for Pyoverdine chromophore), was cloned and sequenced. Mutational inactivation of the pvc genes abrogated Pyoverdine biosynthesis, consistent with their involvement in the biosynthesis of this siderophore. pvcABCD expression was negatively regulated by iron and positively regulated by both PvdS, the alternate sigma factor required for Pyoverdine biosynthesis, and PtxR, a LysR family activator previously implicated in exotoxin A regulation.
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Quorum-sensing and siderophore biosynthesis in Pseudomonas aeruginosa: lasRllasI mutants exhibit reduced Pyoverdine biosynthesis
FEMS microbiology letters, 1998Co-Authors: Alain Stintzi, Jeanmarie Meyer, Kelly Evans, K PooleAbstract:Cell density-dependent gene expression in Pseudomonas aeruginosa is controlled, in part, by the quorum-sensing regulator LasR. lasR null mutants exhibited a reproducible 2-fold decrease in production of the catecholate-hydroxamate siderophore Pyoverdine during grown under iron-limiting conditions. Similarly, lasI mutants defective in the biosynthesis of the autoinducer PAI-1 also exhibited a 2-fold decrease in Pyoverdine production which could be largely restored upon addition of exogenous PAI-1. lasR mutants were not altered with respect to expression of the pvdD gene involved in the synthesis of the peptide portion of Pyoverdine, indicating that some other Pyoverdine biosynthetic gene(s) were affected by the LasRI status of the cell. This represents the first report of quorum-sensing regulation of siderophore production in bacteria and highlights the fact that cell density, while not an essential signal for Pyoverdine expression, does enhance production of this siderophore.
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Pseudomonas aeruginosa : lasR/lasI mutants exhibit reduced Pyoverdine biosynthesis
1998Co-Authors: Alain Stintzi, Jeanmarie Meyer, Kelly Evans, K PooleAbstract:Cell density-dependent gene expression in Pseudomonas aeruginosa is controlled, in part, by the quorum-sensing regulator LasR. IasR null mutants exhibited a reproducible 2-fold decrease in production of the catecholate-hydroxamate siderophore Pyoverdine during grown under iron-limiting conditions. Similarly, lasl mutants defective in the biosynthesis of the autoinducer PAI- also exhibited a 2-fold decrease in Pyoverdine production which could be largely restored upon addition of exogenous PAI-I. IasR mutants were not altered with respect to expression of the pvdD gene involved in the synthesis of the peptide portion of Pyoverdine, indicating that some other Pyoverdine biosynthetic gene(s) were affected by the LasRI status of the cell. This represents the first report of quorum-sensing regulation of siderophore production in bacteria and highlights the fact that cell density, while not an essential signal for Pyoverdine expression, does enhance production of this siderophore. 0 1998 Federation of European Microbiological Societies. Published by Elsevier Science B.V. All rights
Pierre Cornelis - One of the best experts on this subject based on the ideXlab platform.
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Analysis of the draft genome of Pseudomonas fluorescens ATCC17400 indicates a capacity to take up iron from a wide range of sources, including different exogenous Pyoverdines
BioMetals, 2014Co-Authors: Lumeng Ye, Sandra Matthijs, Josselin Bodilis, Falk Hildebrand, Jeroen Raes, Pierre CornelisAbstract:All fluorescent pseudomonads ( Pseudomonas aeruginosa , P. putida , P. fluorescens , P. syringae and others) are known to produce the high-affinity peptidic yellow-green fluorescent siderophore Pyoverdine. These siderophores have peptide chains that are quite diverse and more than 50 Pyoverdine structures have been elucidated. In the majority of the cases, a Pseudomonas species is also able to produce a second siderophore of lower affinity for iron. Pseudomonas fluorescens ATCC 17400 has been shown to produce a unique second siderophore, (thio)quinolobactin, which has an antimicrobial activity against the phytopathogenic Oomycete Pythium debaryanum . We show that this strain has the capacity to utilize 16 different Pyoverdines, suggesting the presence of several ferriPyoverdine receptors. Analysis of the draft genome of P. fluorescens ATCC 17400 confirmed the presence of 55 TonB-dependent receptors, the largest so far for Pseudomonas , among which 15 are predicted to be ferriPyoverdine receptors (Fpv). Phylogenetic analysis revealed the presence of two different clades containing ferriPyoverdine receptors, with sequences similar to the P. aeruginosa type II FpvA forming a separate cluster. Among the other receptors we confirmed the presence of the QbsI (thio)quinolobactin receptor, an ferri-achromobactin and an ornicorrugatin receptor, several catecholate and four putative heme receptors. Twenty five of the receptors genes were found to be associated with genes encoding extracytoplasmic sigma factors (ECF σ) and transmembrane anti-σ sensors.
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A combinatorial approach to the structure elucidation of a Pyoverdine siderophore produced by a Pseudomonas putida isolate and the use of Pyoverdine as a taxonomic marker for typing P. putida subspecies
Biometals : an international journal on the role of metal ions in biology biochemistry and medicine, 2013Co-Authors: Steven Ballet, Sandra Matthijs, Falk Hildebrand, Jeroen Raes, Georges Laus, Karel Guillemyn, José C. Martins, Pierre CornelisAbstract:The structure of a Pyoverdine produced by Pseudomonas putida, W15Oct28, was elucidated by combining mass spectrometric methods and bioinformatics by the analysis of non-ribosomal peptide synthetase genes present in the newly sequenced genome. The only form of Pyoverdine produced by P. putida W15Oct28 is characterized to contain α-ketoglutaric acid as acyl side chain, a dihydroPyoverdine chromophore, and a 12 amino acid peptide chain. The peptide chain is unique among all Pyoverdines produced by Pseudomonas subspecies strains. It was characterized as –l-Asp-l-Ala-d-AOHOrn-l-Thr-Gly-c[l-Thr(O-)-l-Hse-d-Hya-l-Ser-l-Orn-l-Hse-l-Ser-O-]. The chemical formula and the detected and calculated molecular weight of this Pyoverdine are: C65H93N17O32, detected mass 1624.6404 Da, calculated mass 1624.6245. Additionally, Pyoverdine structures from both literature reports and bioinformatics prediction of the genome sequenced P. putida strains are summarized allowing us to propose a scheme based on Pyoverdines structures as tool for the phylogeny of P. putida. This study shows the strength of the combination of in silico analysis together with analytical data and literature mining in determining the structure of secondary metabolites such as peptidic siderophores.
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use of non porous pillar array columns for the separation of pseudomonas Pyoverdine siderophores as an example of a real world biological sample
Journal of Chromatography A, 2009Co-Authors: Hamed Eghbali, Sandra Matthijs, Pierre Cornelis, Vincent Verdoold, Han Gardeniers, Gert DesmetAbstract:We report on the first separation of a complex biomixture in pressure-driven mode using perfectly ordered pillar array columns. The separations were conducted in the reversed-phase mode using a highly aqueous mobile phase, while the outer surface of the non-porous pillars was chemically functionalized with a hydrophobic C8-layer. The samples originated from two different bacterial strains (Pseudomonas aeruginosa PAO1 and Pseudomonas sp. W15Feb38) of fluorescent pseudomonads. These produce fluorescent yellow-green Pyoverdines that serve as siderophores to shuttle iron inside the cell. The Pyoverdines of both strains were prepared from the supernatant through a crude solid phase extraction without any further purification step. In case of the PAO1 mixture, a separation of 15 components within a column length of 2.5 cm could be observed through the transparent cover glass of the chip. For the W15Feb38 mixture, a separation of eight components could be observed within the same distance. These fast chromatographic separations were compared with those obtained via iso-electrofocusing (IEF), which is the traditionally employed fingerprinting method to characterize pseudomonad strains based on their Pyoverdine profiles (siderotyping). With this technique, and despite the injection of a 10,000 times larger sample mass, only nine bands were maximally observed for the PAO1 mixture, whereas maximally six bands were observed in case of the W15Feb38 mixture. The chromatographic pillar array method, yielding a separation in less than 1 min, was also significantly faster than the IEF method, which typically needs 1.5 h. The present system can therefore be considered as a potential alternative fingerprinting tool for the fast identification of different strains of fluorescent pseudomonads, including as diagnostic tool for typing strains of the important opportunistic pathogen P. aeruginosa
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Siderophore-mediated iron acquisition in the entomopathogenic bacterium Pseudomonas entomophila L48 and its close relative Pseudomonas putida KT2440.
BioMetals, 2009Co-Authors: Sandra Matthijs, Jeanmarie Meyer, Herbert Budzikiewicz, Georges Laus, Kourosch Abbaspour-tehrani, Mathias Schäfer, Pierre CornelisAbstract:Pseudomonas entomophila L48 is a recently identified entomopathogenic bacterium which, upon ingestion, kills Drosophila melanogaster, and is closely related to P. putida. The complete genome of this species has been sequenced and therefore a genomic, genetic and structural analysis of the siderophore-mediated iron acquisition was undertaken. P. entomophila produces two siderophores, a structurally new and unique Pyoverdine and the secondary siderophore pseudomonine, already described in P. fluorescens species. Structural analysis of the Pyoverdine produced by the closely related P. putida KT2440 showed that this strain produces an already characterised Pyoverdine, but different from P. entomophila, and no evidence was found for the production of a second siderophore. Growth stimulation assays with heterologous Pyoverdines demonstrated that P. entomophila is able to utilize a large variety of structurally distinct Pyoverdines produced by other Pseudomonas species. In contrast, P. putida KT2440 is able to utilize only its own Pyoverdine and the Pyoverdine produced by P. syringae LMG 1247. Our data suggest that although closely related, P. entomophila is a more efficient competitor for iron than P. putida.
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Impaired maturation of the siderophore Pyoverdine chromophore in Pseudomonas fluorescens ATCC 17400 deficient for the cytochrome c biogenesis protein CcmC.
FEBS letters, 2002Co-Authors: Christine Baysse, Herbert Budzikiewicz, Diana Uría Fernández, Pierre CornelisAbstract:Pyoverdines are the main siderophores of fluorescent pseudomonads. They comprise a quinoline chromophore, a peptide chain, and a dicarboxylic acid or a dicarboxylic acid amide side chain. Each Pseudomonas species produces a Pyoverdine with a different peptide chain. A cytochrome c biogenesis DeltaccmC mutant of Pseudomonas fluorescens ATCC 17400 produces multiple Pyoverdine forms, showing differences at the level of the chromophore or the side chain. When grown in the presence of L-cysteine, DeltaccmC produces only ferribactin, a non-fluorescent precursor of Pyoverdine, while addition of oxidized glutathione improves Pyoverdine production. We suggest that the conversion of ferribactin to Pyoverdine does not take place in the DeltaccmC mutant because of lack of oxidizing power in the periplasm.
Iain L. Lamont - One of the best experts on this subject based on the ideXlab platform.
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Interactions between an anti-sigma protein and two sigma factors that regulate the Pyoverdine signaling pathway in Pseudomonas aeruginosa
BMC microbiology, 2014Co-Authors: Rebecca J. Edgar, Lois W. Martin, David F. Ackerley, Matt Shirley, Anna F. Konings, Iain L. LamontAbstract:Background Synthesis and uptake of Pyoverdine, the primary siderophore of the opportunistic pathogen Pseudomonas aeruginosa, is dependent on two extra-cytoplasmic function (ECF) sigma factors, FpvI and PvdS. FpvI and PvdS are required for expression of the ferri-Pyoverdine receptor gene fpvA and of Pyoverdine synthesis genes respectively. In the absence of Pyoverdine the anti-sigma factor FpvR that spans the cytoplasmic membrane inhibits the activities of both FpvI and PvdS, despite the two sigma factors having low sequence identity.
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Biosynthesis of novel Pyoverdines by domain substitution in a nonribosomal peptide synthetase of Pseudomonas aeruginosa.
Applied and environmental microbiology, 2014Co-Authors: Mark J. Calcott, Iain L. Lamont, Jeremy G. Owen, David F. AckerleyAbstract:Pyoverdine is a fluorescent nonribosomal peptide siderophore made by fluorescent pseudomonads. The Pseudomonas aeruginosa nonribosomal peptide synthetase (NRPS) PvdD contains two modules that each incorporate an l-threonine residue at the C-terminal end of Pyoverdine. In an attempt to generate modified Pyoverdine peptides, we substituted alternative-substrate-specifying adenylation (A) and peptide bond-catalyzing condensation (C) domains into the second module of PvdD. When just the A domain was substituted, the resulting strains produced only wild-type Pyoverdine-at high levels if the introduced A domain specified threonine or at trace levels otherwise. The high levels of Pyoverdine synthesis observed whenever the introduced A domain specified threonine indicated that these nonnative A domains were able to communicate effectively with the PvdD C domain. Moreover, the unexpected observation that non-threonine-specifying A domains nevertheless incorporated threonine into Pyoverdine suggests that the native PvdD C domain exhibited stronger selectivity than these A domains for the incorporated amino acid substrate (i.e., misactivation of a threonine residue by the introduced A domains was more frequent than misincorporation of a nonthreonine residue by the PvdD C domain). In contrast, substitution of both the C and A domains of PvdD generated high yields of rationally modified Pyoverdines in two instances, these Pyoverdines having either a lysine or a serine residue in place of the terminal threonine. However, C-A domain substitution more commonly yielded a truncated peptide product, likely due to stalling of synthesis on a nonfunctional recombinant NRPS template.
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synthesis of the siderophore Pyoverdine in pseudomonas aeruginosa involves a periplasmic maturation
Amino Acids, 2010Co-Authors: Emilie Yeterian, Laurent Guillon, Iain L. Lamont, Lois W. Martin, Laure Journet, Isabelle J. SchalkAbstract:Pyoverdines, the main siderophores produced by fluorescent Pseudomonads, comprise a fluorescent dihydroxyquinoline chromophore attached to a strain-specific peptide. These molecules are thought to be synthesized as non-fluorescent precursor peptides that are then modified to give functional Pyoverdines. Using the fluorescent properties of PVDI, the Pyoverdine produced by Pseudomonas aeruginosa PAO1, we were able to show that PVDI was not present in the cytoplasm of the bacteria, but large amounts of a fluorescent PVDI precursor PVDIp were stored in the periplasm. Like PVDI, PVDIp is able to transport iron into P. aeruginosa cells. Mutation of genes encoding the periplasmic PvdN, PvdO and PvdP proteins prevented accumulation of PVDIp in the periplasm and secretion of PVDI into the growth medium, indicating that these three enzymes are involved in PVDI synthesis. Mutation of the gene encoding PvdQ resulted in the presence of fluorescent PVDI precursor in the periplasm and secretion of a functional fluorescent siderophore that had different isoelectric properties to PVDI, suggesting a role for PvdQ in the periplasmic maturation of PVDI. Mutation of the gene encoding the export ABC transporter PvdE prevented PVDI production and accumulation of PVDIp in the periplasm. These data are consistent with a model in which a PVDI precursor peptide is synthesized in the cytoplasm and exported to the periplasm by PvdE where siderophore maturation, including formation of the chromophore moiety, occurs in a process involving the PvdN, PvdO, PvdP and PvdQ proteins.
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Role of TonB1 in Pyoverdine-Mediated Signaling in Pseudomonas aeruginosa
Journal of bacteriology, 2009Co-Authors: Matt Shirley, Iain L. LamontAbstract:Pyoverdines are siderophores secreted by Pseudomonas aeruginosa. Uptake of ferriPyoverdine in P. aeruginosa PAO1 occurs via the FpvA receptor protein and requires the energy-transducing protein TonB1. Interaction of (ferri)Pyoverdine with FpvA activates Pyoverdine gene expression in a signaling process involving the cytoplasmic-membrane-spanning anti-sigma factor FpvR and the sigma factor PvdS. Here, we show that mutation of a region of FpvA that interacts with TonB1 (the TonB box) prevents this signaling process, as well as inhibiting bacterial growth in the presence of the iron-chelating compound ethylenediamine-di(o-hydroxy-phenylacetic acid). Signaling via wild-type FpvA was also eliminated in strains lacking TonB1 but was unaffected in strains lacking either (or both) of two other TonB proteins in P. aeruginosa, TonB2 and TonB3. An absence of Pyoverdine-mediated signaling corresponded with proteolysis of PvdS. These data show that interactions between FpvA and TonB1 are required for (ferri)Pyoverdine signal transduction, as well as for ferriPyoverdine transport, consistent with a mechanistic link between the signaling and transport functions of FpvA.
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Adsorption to metal oxides of the Pseudomonas aeruginosa siderophore Pyoverdine and implications for bacterial biofilm formation on metals.
Langmuir : the ACS journal of surfaces and colloids, 2007Co-Authors: Hamish G. Upritchard, Iain L. Lamont, Jing Yang, Philip J. Bremer, A. James McquillanAbstract:The initiation of biofilm formation is poorly understood, and in particular, the contribution of chemical bond formation between bacterial cells and metal surfaces has received little attention. We have previously used in situ infrared spectroscopy to show, during the initial stages of Pseudomonas aeruginosa biofilm formation, the formation of coordinate covalent bonds between titanium dioxide particle films and Pyoverdine, a mixed catecholate and hydroxamate siderophore. Here we show using infrared spectroscopy that Pyoverdine can also form covalent bonds with particle films of Fe2O3, CrOOH, and AlOOH. Adsorption to the metal oxides through the catechol-like 2,3-diamino-6,7-dihydroxyquinoline part of Pyoverdine was most evident in the infrared spectrum of the adsorbed Pyoverdine molecule. Weaker infrared absorption bands that are consistent with the hydroxamic acids of Pyoverdine binding covalently to TiO2, Fe2O3, and AlOOH surfaces were also observed. The adsorption of Pyoverdine to TiO2 and Fe2O3 surfa...
Philippe Lemanceau - One of the best experts on this subject based on the ideXlab platform.
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The Pseudomonas fluorescens Siderophore Pyoverdine Weakens Arabidopsis thaliana Defense in Favor of Growth in Iron-Deficient Conditions
Plant physiology, 2016Co-Authors: Pauline L Trapet, Sylvie Mazurier, Philippe Lemanceau, Laure Avoscan, Agnès Klinguer, Stéphanie Pateyron, Sylvie Citerne, Christian Chervin, David Wendehenne, Angélique Besson-bardAbstract:Pyoverdines are siderophores synthesized by fluorescent Pseudomonas spp. Under iron-limiting conditions, these high-affinity ferric iron chelators are excreted by bacteria in the soil to acquire iron. Pyoverdines produced by beneficial Pseudomonas spp. ameliorate plant growth. Here, we investigate the physiological incidence and mode of action of Pyoverdine from Pseudomonas fluorescens C7R12 on Arabidopsis (Arabidopsis thaliana) plants grown under iron-sufficient or iron-deficient conditions. Pyoverdine was provided to the medium in its iron-free structure (apo-Pyoverdine), thus mimicking a situation in which it is produced by bacteria. Remarkably, apo-Pyoverdine abolished the iron-deficiency phenotype and restored the growth of plants maintained in the iron-deprived medium. In contrast to a P. fluorescens C7R12 strain impaired in apo-Pyoverdine production, the wild-type C7R12 reduced the accumulation of anthocyanins in plants grown in iron-deficient conditions. Under this condition, apo-Pyoverdine modulated the expression of around 2,000 genes. Notably, apo-Pyoverdine positively regulated the expression of genes related to development and iron acquisition/redistribution while it repressed the expression of defense-related genes. Accordingly, the growth-promoting effect of apo-Pyoverdine in plants grown under iron-deficient conditions was impaired in iron-regulated transporter1 and ferric chelate reductase2 knockout mutants and was prioritized over immunity, as highlighted by an increased susceptibility to Botrytis cinerea This process was accompanied by an overexpression of the transcription factor HBI1, a key node for the cross talk between growth and immunity. This study reveals an unprecedented mode of action of Pyoverdine in Arabidopsis and demonstrates that its incidence on physiological traits depends on the plant iron status.
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Ferric-Pyoverdine Recognition by Fpv Outer Membrane Proteins of Pseudomonas protegens Pf-5
Journal of bacteriology, 2012Co-Authors: Sierra L. Hartney, Sylvie Mazurier, Maëva K. Girard, Samina Mehnaz, Edward W. Davis, Harald Gross, Philippe Lemanceau, Joyce E. LoperAbstract:The soil bacterium Pseudomonas protegens Pf-5 (previously called P. fluorescens Pf-5) produces two siderophores, enantio-pyochelin and a compound in the large and diverse Pyoverdine family. Using high-resolution mass spectroscopy, we determined the structure of the Pyoverdine produced by Pf-5. In addition to producing its own siderophores, Pf-5 also utilizes ferric complexes of some Pyoverdines produced by other strains of Pseudomonas spp. as sources of iron. Previously, phylogenetic analysis of the 45 TonB-dependent outer membrane proteins in Pf-5 indicated that six are in a well-supported clade with ferric-Pyoverdine receptors (Fpvs) from other Pseudomonas spp. We used a combination of phylogenetics, bioinformatics, mutagenesis, Pyoverdine structural determinations, and cross-feeding bioassays to assign specific ferric-Pyoverdine substrates to each of the six Fpvs of Pf-5. We identified at least one ferric-Pyoverdine that was taken up by each of the six Fpvs of Pf-5. Functional redundancy of the Pf-5 Fpvs was also apparent, with some ferric-Pyoverdines taken up by all mutants with a single Fpv deletion but not by a mutant having deletions in two of the Fpv-encoding genes. Finally, we demonstrated that phylogenetically related Fpvs take up ferric complexes of structurally related Pyoverdines, thereby establishing structure-function relationships that can be employed in the future to predict the Pyoverdine substrates of Fpvs in other Pseudomonas spp.
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Variation in the TonB-dependent outer-membrane proteins in plant-associated strains of Pseudomonas fluorescens
2011Co-Authors: Sierra L. Hartney, Sylvie Mazurier, Philippe Lemanceau, Joyce E. LoperAbstract:Genomic sequences of ten strains of plant-associated Pseudomonas spp. were surveyed for the presence of TonB-dependent outer-membrane proteins (TBDPs), which function in the uptake of substrates from the environment by many Gram-negative bacteria. The ten strains represent P. fluorescens, P. chlororaphis, and P. synxantha isolated from the phyllosphere, rhizosphere or soil. 14 to 45 TBDPs were identified in each strain, and phylogenetic analysis of the TBDPs identified five that are conserved across all ten genomes. Comparisons to proteins with known functions allowed the assignment of putative roles in uptake of heme, vitamin B12, copper, and the siderophore ferrichrome to the conserved TBDPs. Each strain also has multiple TBDPs with predicted functions in the uptake of Pyoverdines, a structurally diverse class of siderophores produced by the fluorescent pseudomonads. For example, strain Pf-5 has six such TBDPs. Using crossfeeding assays, we found that Pf-5 utilized Pyoverdines having 17 distinct structures. Mutants of Pf-5 lacking each of the six putative Pyoverdine receptors were constructed and tested in crossfeeding assays, which linked the uptake of specific Pyoverdines to individual TBDPs. The identification of the core TBDPs present in all genomes as well as the TBDPs unique to each genome highlights functions conserved across the species as well as those specific to the distinctive lifestyles of each strain.
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Diversity of TonB-dependent outer-membrane proteins in plant-associated strains of Pseudomonas fluorescens
2011Co-Authors: Sierra L. Hartney, Sylvie Mazurier, Philippe Lemanceau, Joyce E. LoperAbstract:Genomic sequences of ten strains of plant-associated Pseudomonas spp. were surveyed for the presence of TonB-dependent outer-membrane proteins (TBDPs), which function in the uptake of substrates from the environment by many Gram-negative bacteria. The ten strains represent P. fluorescens, P. chlororaphis, and P. synxantha isolated from the phyllosphere, rhizosphere or soil. 14 to 45 TBDPs were identified in each strain, and phylogenetic analysis of the TBDPs identified five that are conserved across all ten genomes. Comparisons to proteins with known functions allowed the assignment of putative roles in uptake of heme, vitamin B12, copper, and the siderophore ferrichrome to the conserved TBDPs. Each strain also has multiple TBDPs with predicted functions in the uptake of Pyoverdines, a structurally diverse class of siderophores produced by the fluorescent pseudomonads. For example, strain Pf-5 has six such TBDPs. Using crossfeeding assays, we found that Pf-5 utilized Pyoverdines having 17 distinct structures. Mutants of Pf-5 lacking each of the six putative Pyoverdine receptors were constructed and tested in crossfeeding assays, which linked the uptake of specific Pyoverdines to individual TBDPs. The identification of the core TBDPs present in all genomes as well as the TBDPs unique to each genome highlights functions conserved across the species as well as those specific to the distinctive lifestyles of each strain.
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TonB-dependent outer-membrane proteins and siderophore utilization in Pseudomonas fluorescens Pf-5
BioMetals, 2011Co-Authors: Sierra L. Hartney, Sylvie Mazurier, Philippe Lemanceau, Teresa A. Kidarsa, Maria Carolina Quecine, Joyce E. LoperAbstract:The soil bacterium Pseudomonas fluorescens Pf-5 produces two siderophores, a Pyoverdine and enantio-pyochelin, and its proteome includes 45 TonB-dependent outer-membrane proteins, which commonly function in uptake of siderophores and other substrates from the environment. The 45 proteins share the conserved β-barrel and plug domains of TonB-dependent proteins but only 18 of them have an N-terminal signaling domain characteristic of TonB-dependent transducers (TBDTs), which participate in cell-surface signaling systems. Phylogenetic analyses of the 18 TBDTs and 27 TonB-dependent receptors (TBDRs), which lack the N-terminal signaling domain, suggest a complex evolutionary history including horizontal transfer among different microbial lineages. Putative functions were assigned to certain TBDRs and TBDTs in clades including well-characterized orthologs from other Pseudomonas spp. A mutant of Pf-5 with deletions in Pyoverdine and enantio-pyochelin biosynthesis genes was constructed and characterized for iron-limited growth and utilization of a spectrum of siderophores. The mutant could utilize as iron sources a large number of Pyoverdines with diverse structures as well as ferric citrate, heme, and the siderophores ferrichrome, ferrioxamine B, enterobactin, and aerobactin. The diversity and complexity of the TBDTs and TBDRs with roles in iron uptake clearly indicate the importance of iron in the fitness and survival of Pf-5 in the environment.
