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Juan M Tomas - One of the best experts on this subject based on the ideXlab platform.

  • the polar and lateral flagella from Plesiomonas shigelloides are glycosylated with legionaminic acid
    Frontiers in Microbiology, 2015
    Co-Authors: Susana Merino, Eleonora Aquilini, Kelly M Fulton, Susan M Twine, Juan M Tomas
    Abstract:

    Plesiomonas shigelloides is the unique member of the Enterobacteriaceae family able to produce polar flagella when grow in liquid medium and lateral flagella when grown in solid or semisolid media. In this study on P. shigelloides 302-73 strain, we found two different gene clusters, one exclusively for the lateral flagella biosynthesis and the other one containing the biosynthetic polar flagella genes with additional putative glycosylation genes. P. shigelloides is the first Enterobacteriaceae were a complete lateral flagella cluster leading to a lateral flagella production is described. We also show that both flagella in P. shigelloides 302-73 strain are glycosylated by a derivative of legionaminic acid (Leg), which explains the presence of Leg pathway genes between the two polar flagella regions in their biosynthetic gene cluster. It is the first bacterium reported with O-glycosylated Leg in both polar and lateral flagella. The flagella O-glycosylation is essential for bacterial flagella formation, either polar or lateral, because gene mutants on the biosynthesis of Leg are non-flagellated. Furthermore, the presence of the lateral flagella cluster and Leg O-flagella glycosylation genes are widely spread features among the P. shigelloides strains tested.

  • genomic and proteomic studies on Plesiomonas shigelloides lipopolysaccharide core biosynthesis
    Journal of Bacteriology, 2014
    Co-Authors: Eleonora Aquilini, Susana Merino, Miguel Regue, Juan M Tomas
    Abstract:

    We report here the identification of waa clusters with the genes required for the biosynthesis of the core lipopolysaccharides (LPS) of two Plesiomonas shigelloides strains. Both P. shigelloides waa clusters shared all of the genes besides the ones flanking waaL. In both strains, all of the genes were found in the waa gene cluster, although one common core biosynthetic gene (wapG) was found in a different chromosome location outside the cluster. Since P. shigelloides and Klebsiella pneumoniae share a core LPS carbohydrate backbone extending up at least to the second outer-core residue, the functions of the common P. shigelloides genes were elucidated by genetic complementation studies using well-defined K. pneumoniae mutants. The function of strain-specific inner- or outer-core genes was identified by using as a surrogate acceptor LPS from three well-defined K. pneumoniae core LPS mutants. Using this strategy, we were able to assign a proteomic function to all of the P. shigelloides waa genes identified in the two strains encoding six new glycosyltransferases (WapA, -B, -C, -D, -F, and -G). P. shigelloides demonstrated an important variety of core LPS structures, despite being a single species of the genus, as well as high homologous recombination in housekeeping genes.

  • the Plesiomonas shigelloides wbo1 gene cluster and the role of o1 antigen lps in pathogenicity
    Microbial Pathogenesis, 2013
    Co-Authors: Eleonora Aquilini, Susana Merino, Juan M Tomas
    Abstract:

    The Plesiomonas shigelloides 302-73 strain (serotype O1) wb gene cluster encodes 15 proteins which are consistent with the chemical structure of the O1-antigen lypopolysaccharide (LPS) previously described for this strain. The P. shigelloides O1-antigen LPS export uses the Wzy-dependent pathway as correspond to heteropolysaccharides structures. By the isolation of two mutants lacking this O1-antigen LPS, we could establish that the presence of the O1-antigen LPS is crucial for to survive in serum mainly to become resistant to complement. Also, it is an important factor in the bacterial adhesion and invasion to some eukaryotic cells, and in the ability to form biofilms. This is the first report on the genetics from a P. shigelloides O-antigen LPS cluster (wb) not shared by Shigella like P. shigelloides O17, the only one reported until now.

  • genome sequence of Plesiomonas shigelloides strain 302 73 serotype o1
    Genome Announcements, 2013
    Co-Authors: Nuria Pique, Eleonora Aquilini, Tyler Alioto, David Minanagalbis, Juan M Tomas
    Abstract:

    ABSTRACT Plesiomonas shigelloides, the only species of the genus, is an emergent pathogenic bacterium associated with human diarrheal and extraintestinal disease. We present the whole-genome sequence analysis of the representative strain for the O1 serotype (strain 302-73), providing a tool for studying bacterial outbreaks, virulence factors, and accurate diagnostic methods.

  • structure of the core region from the lipopolysaccharide of Plesiomonas shigelloides strain 302 73 serotype o1
    European Journal of Organic Chemistry, 2009
    Co-Authors: Giuseppina Pieretti, Maria Michela Corsaro, Rosa Lanzetta, Michelangelo Parrilli, Susana Merino, Silvia Vilches, Juan M Tomas
    Abstract:

    Plesiomonas shigelloides is a Gram-negative pathogenic bacterium belonging to the Enterobacteriaceae family. To date, only few lipopolysaccharide (LPS) structures from P. shigelloides strains are known. In particular, three core oligosaccharides have been found. Recently, we elucidated the structure of the O-antigen of P. shigelloides 302-73 (serotype O1) and in this paper we present the characterization of the core structure from the LPS of the same strain. The LPS was hydrolyzed under both alkaline and mildly acidic conditions. In both cases, a mixture of oligosaccharides was obtained, which was purified by gel filtration and HPAEC. The oligosaccharides were characterized by chemical analysis, 2D NMR spectroscopy and MALDI-TOF mass spectrometry. A new core structure was found for P. shigelloides. In particular, from the analysis of the acid hydrolysed product it was possible to reveal the presence of a of D-glycero-D-talo-2-octulopyranosonic acid (Ko) residue, which substitutes in part the terminal 3-deoxy-D-manno-oct-2-ulosonic acid (Kdo) unit. The Ko residue is not frequently found in core structures.(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)

Czeslaw Lugowski - One of the best experts on this subject based on the ideXlab platform.

Doug Henderson - One of the best experts on this subject based on the ideXlab platform.

  • development of a method to produce hemoglobin in a bioreactor culture of escherichia coli bl21 de3 transformed with a plasmid containing Plesiomonas shigelloides heme transport genes and modified human hemoglobin genes
    Applied and Environmental Microbiology, 2011
    Co-Authors: Bryan J Z Smith, P Gutierrez, E Guerrero, C J Brewer, Doug Henderson
    Abstract:

    We describe a method for production of recombinant human hemoglobin by Escherichia coli grown in a bioreactor. E. coli BL21(DE3) transformed with a plasmid containing hemoglobin genes and Plesiomonas shigelloides heme transport genes reached a cell dry weight of 83.64 g/liter and produced 11.92 g/liter of hemoglobin in clarified lysates.

  • Enhancement of Recombinant Hemoglobin Production in Escherichia coli BL21(DE3) Containing the Plesiomonas shigelloides Heme Transport System
    Applied and Environmental Microbiology, 2008
    Co-Authors: D. M. Villarreal, John S. Olson, C. L. Phillips, A. M. Kelley, S. Villarreal, A. Villaloboz, P. Hernandez, Doug Henderson
    Abstract:

    To produce recombinant hemoglobin in Escherichia coli, sufficient intracellular heme must be present, or the protein folds improperly and is degraded. In this study, coexpression of human hemoglobin genes and Plesiomonas shigelloides heme transport genes enhanced recombinant hemoglobin production in E. coli BL21(DE3) grown in medium containing heme.

  • characterization of the Plesiomonas shigelloides genes encoding the heme iron utilization system
    Journal of Bacteriology, 2001
    Co-Authors: Doug Henderson, Elizabeth E Wyckoff, C E Rashidi, H Verlei, Athenia L Oldham
    Abstract:

    Plesiomonas shigelloides is a gram-negative pathogen which can utilize heme as an iron source. In previous work, P. shigelloides genes which permitted heme iron utilization in a laboratory strain of Escherichia coli were isolated. In the present study, the cloned P. shigelloides sequences were found to encode ten potential heme utilization proteins: HugA, the putative heme receptor; TonB and ExbBD; HugB, the putative periplasmic binding protein; HugCD, the putative inner membrane permease; and the proteins HugW, HugX, and HugZ. Three of the genes, hugA, hugZ, and tonB, contain a Fur box in their putative promoters, indicating that the genes may be iron regulated. When the P. shigelloides genes were tested in E. coli K-12 or in a heme iron utilization mutant of P. shigelloides, hugA, the TonB system genes, and hugW, hugX, or hugZ were required for heme iron utilization. When the genes were tested in a hemA entB mutant of E. coli, hugWXZ were not required for utilization of heme as a porphyrin source, but their absence resulted in heme toxicity when the strains were grown in media containing heme as an iron source. hugA could replace the Vibrio cholerae hutA in a heme iron utilization assay, and V. cholerae hutA could complement a P. shigelloides heme utilization mutant, suggesting that HugA is the heme receptor. Our analyses of the TonB system of P. shigelloides indicated that it could function in tonB mutants of both E. coli and V. cholerae and that it was similar to the V. cholerae TonB1 system in the amino acid sequence of the proteins and in the ability of the system to function in high-salt medium.

Susana Merino - One of the best experts on this subject based on the ideXlab platform.

  • the polar and lateral flagella from Plesiomonas shigelloides are glycosylated with legionaminic acid
    Frontiers in Microbiology, 2015
    Co-Authors: Susana Merino, Eleonora Aquilini, Kelly M Fulton, Susan M Twine, Juan M Tomas
    Abstract:

    Plesiomonas shigelloides is the unique member of the Enterobacteriaceae family able to produce polar flagella when grow in liquid medium and lateral flagella when grown in solid or semisolid media. In this study on P. shigelloides 302-73 strain, we found two different gene clusters, one exclusively for the lateral flagella biosynthesis and the other one containing the biosynthetic polar flagella genes with additional putative glycosylation genes. P. shigelloides is the first Enterobacteriaceae were a complete lateral flagella cluster leading to a lateral flagella production is described. We also show that both flagella in P. shigelloides 302-73 strain are glycosylated by a derivative of legionaminic acid (Leg), which explains the presence of Leg pathway genes between the two polar flagella regions in their biosynthetic gene cluster. It is the first bacterium reported with O-glycosylated Leg in both polar and lateral flagella. The flagella O-glycosylation is essential for bacterial flagella formation, either polar or lateral, because gene mutants on the biosynthesis of Leg are non-flagellated. Furthermore, the presence of the lateral flagella cluster and Leg O-flagella glycosylation genes are widely spread features among the P. shigelloides strains tested.

  • genomic and proteomic studies on Plesiomonas shigelloides lipopolysaccharide core biosynthesis
    Journal of Bacteriology, 2014
    Co-Authors: Eleonora Aquilini, Susana Merino, Miguel Regue, Juan M Tomas
    Abstract:

    We report here the identification of waa clusters with the genes required for the biosynthesis of the core lipopolysaccharides (LPS) of two Plesiomonas shigelloides strains. Both P. shigelloides waa clusters shared all of the genes besides the ones flanking waaL. In both strains, all of the genes were found in the waa gene cluster, although one common core biosynthetic gene (wapG) was found in a different chromosome location outside the cluster. Since P. shigelloides and Klebsiella pneumoniae share a core LPS carbohydrate backbone extending up at least to the second outer-core residue, the functions of the common P. shigelloides genes were elucidated by genetic complementation studies using well-defined K. pneumoniae mutants. The function of strain-specific inner- or outer-core genes was identified by using as a surrogate acceptor LPS from three well-defined K. pneumoniae core LPS mutants. Using this strategy, we were able to assign a proteomic function to all of the P. shigelloides waa genes identified in the two strains encoding six new glycosyltransferases (WapA, -B, -C, -D, -F, and -G). P. shigelloides demonstrated an important variety of core LPS structures, despite being a single species of the genus, as well as high homologous recombination in housekeeping genes.

  • the Plesiomonas shigelloides wbo1 gene cluster and the role of o1 antigen lps in pathogenicity
    Microbial Pathogenesis, 2013
    Co-Authors: Eleonora Aquilini, Susana Merino, Juan M Tomas
    Abstract:

    The Plesiomonas shigelloides 302-73 strain (serotype O1) wb gene cluster encodes 15 proteins which are consistent with the chemical structure of the O1-antigen lypopolysaccharide (LPS) previously described for this strain. The P. shigelloides O1-antigen LPS export uses the Wzy-dependent pathway as correspond to heteropolysaccharides structures. By the isolation of two mutants lacking this O1-antigen LPS, we could establish that the presence of the O1-antigen LPS is crucial for to survive in serum mainly to become resistant to complement. Also, it is an important factor in the bacterial adhesion and invasion to some eukaryotic cells, and in the ability to form biofilms. This is the first report on the genetics from a P. shigelloides O-antigen LPS cluster (wb) not shared by Shigella like P. shigelloides O17, the only one reported until now.

  • structure of the core region from the lipopolysaccharide of Plesiomonas shigelloides strain 302 73 serotype o1
    European Journal of Organic Chemistry, 2009
    Co-Authors: Giuseppina Pieretti, Maria Michela Corsaro, Rosa Lanzetta, Michelangelo Parrilli, Susana Merino, Silvia Vilches, Juan M Tomas
    Abstract:

    Plesiomonas shigelloides is a Gram-negative pathogenic bacterium belonging to the Enterobacteriaceae family. To date, only few lipopolysaccharide (LPS) structures from P. shigelloides strains are known. In particular, three core oligosaccharides have been found. Recently, we elucidated the structure of the O-antigen of P. shigelloides 302-73 (serotype O1) and in this paper we present the characterization of the core structure from the LPS of the same strain. The LPS was hydrolyzed under both alkaline and mildly acidic conditions. In both cases, a mixture of oligosaccharides was obtained, which was purified by gel filtration and HPAEC. The oligosaccharides were characterized by chemical analysis, 2D NMR spectroscopy and MALDI-TOF mass spectrometry. A new core structure was found for P. shigelloides. In particular, from the analysis of the acid hydrolysed product it was possible to reveal the presence of a of D-glycero-D-talo-2-octulopyranosonic acid (Ko) residue, which substitutes in part the terminal 3-deoxy-D-manno-oct-2-ulosonic acid (Kdo) unit. The Ko residue is not frequently found in core structures.(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)

  • structural studies of the o chain polysaccharide from Plesiomonas shigelloides strain 302 73 serotype o1
    European Journal of Organic Chemistry, 2008
    Co-Authors: Giuseppina Pieretti, Maria Michela Corsaro, Rosa Lanzetta, Michelangelo Parrilli, Rocio Canals, Susana Merino, Juan M Tomas
    Abstract:

    Plesiomonas shigelloides is a Gram-negative bacterium belonging to the Enterobacteriaceae family. It has been found in an aquatic environment in the tropical and subtropical regions and is responsible for many gastrointestinal infections in humans, which take place from drinking untreated water or eating uncooked shellfish. Plesiomonas shigelloides has also been reported to provoke extraintestinal infections such as meningitis and bacteremia in immunocompromised adults and neonates. Despite the emerging importance of this pathogenic microorganism, only three different O-antigens have been characterised so far. The structure of the O-chain of the lipopolysaccharide (LPS) from Plesiomonasshigelloides strain 302–73 (serotype O1) was determined by chemical analysis, 1D and 2D NMR spectroscopy and MALDI-TOF mass spectrometry. The polysaccharide was constituted by a linear pentasaccharidic repeating unit as follows: 3)-α-L-PneNAc4OAc(14)-α-L-FucNAc(14)-α-L-FucNAc(14)-α-L-FucNAc(13)-β-D-QuiNAc4NHb(1 (PneNAc = 2-acetamido-2,6-dideoxy-talose, Hb = (S)-3-hydroxybutanoyl) PneNAc O-acetylation was not stoichiometric and was found to be about 75 %. The position of the O-acetyl group and the amount of acetylation were deduced by NMR spectroscopic analysis. All the monosaccharides included in the repeating unit were deoxyamino sugars, which most probably, together with the presence of O-acetyl groups, were responsible for the recovery of the LPS in the phenol layer of the phenol/water extract of dried bacteria cells.(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)

Tomasz Niedziela - One of the best experts on this subject based on the ideXlab platform.