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A W D Lepper - One of the best experts on this subject based on the ideXlab platform.

  • characterization of pilin genes from seven serologically defined prototype strains of Moraxella bovis
    Journal of Bacteriology, 1994
    Co-Authors: J L Atwell, A W D Lepper, Jan M Tennent, T C Elleman
    Abstract:

    Abstract Numerous field isolates of Moraxella bovis have previously been classified by serological techniques into seven serogroups, each defined by homologous cross-reaction with antisera prepared against purified pili of a single prototype strain. The gene encoding pilin from each of the prototype strains has been characterized by nucleotide sequence determination. The coding sequences show extensive homology (70 to 80%) while the proximal downstream sequences show a dichotomy into nonhomologous sets. The pilin genes of three more strains were also characterized. The presence of an additional, partial pilin gene in each prototype strain was confirmed by Southern blot analysis, and the partial pilin genes from two strains of one serogroup were characterized by sequence determination. Features of the pilin gene sequences are considered in relation to pilin gene inversion and the serological variants of strains which may arise from gene inversion events.

  • a unified serotyping scheme for Moraxella bovis
    Veterinary Microbiology, 1991
    Co-Authors: L J Moore, A W D Lepper
    Abstract:

    Abstract Fifty-three Australian, seven British, two American and two New Zealand isolates of Moraxella bovis were classified into seven serogroups on the basis of their variable fimbrial (pilus) antigens using whole cell slide agglutination (SA), enzyme-linked immunosorbent assays (ELISA) and tandem-crossed immunoelectrophoresis (TCIE). Although results of serogroup classification by SA and ELISA were identical in 68.7% of isolates, it was found necessary to resolve the discrepancies between the two systems using TCIE. Results suggest that world-wide variation in the potentially host-protective fimbrial antigens of M. bovis may be relatively limited. It is proposed that the previous numerical classifications of British and Australian serogroups are appropriately amalgamated as a result of this latest study and are designated as serogroups A to G inclusive. A protocol for the further serotyping of fresh, fimbriate isolates of M. bovis is suggested.

  • characterization of the pilin gene of Moraxella bovis dalton 2d and expression of pili from m bovis in pseudomonas aeruginosa
    Infection and Immunity, 1990
    Co-Authors: T C Elleman, Peter A Hoyne, A W D Lepper
    Abstract:

    The pilin gene of Moraxella bovis Dalton 2d was isolated by cloning in Pseudomonas aeruginosa. The nucleotide sequence of this gene encodes a prepilin of 156 amino acid residues. When high levels of pilin were expressed from the gene in P. aeruginosa, by using the pL promoter of bacteriophage lambda inserted upstream of the coding sequence, pili which were indistinguishable from pili of M. bovis were produced.

T C Elleman - One of the best experts on this subject based on the ideXlab platform.

  • characterization of pilin genes from seven serologically defined prototype strains of Moraxella bovis
    Journal of Bacteriology, 1994
    Co-Authors: J L Atwell, A W D Lepper, Jan M Tennent, T C Elleman
    Abstract:

    Abstract Numerous field isolates of Moraxella bovis have previously been classified by serological techniques into seven serogroups, each defined by homologous cross-reaction with antisera prepared against purified pili of a single prototype strain. The gene encoding pilin from each of the prototype strains has been characterized by nucleotide sequence determination. The coding sequences show extensive homology (70 to 80%) while the proximal downstream sequences show a dichotomy into nonhomologous sets. The pilin genes of three more strains were also characterized. The presence of an additional, partial pilin gene in each prototype strain was confirmed by Southern blot analysis, and the partial pilin genes from two strains of one serogroup were characterized by sequence determination. Features of the pilin gene sequences are considered in relation to pilin gene inversion and the serological variants of strains which may arise from gene inversion events.

  • characterization of the pilin gene of Moraxella bovis dalton 2d and expression of pili from m bovis in pseudomonas aeruginosa
    Infection and Immunity, 1990
    Co-Authors: T C Elleman, Peter A Hoyne, A W D Lepper
    Abstract:

    The pilin gene of Moraxella bovis Dalton 2d was isolated by cloning in Pseudomonas aeruginosa. The nucleotide sequence of this gene encodes a prepilin of 156 amino acid residues. When high levels of pilin were expressed from the gene in P. aeruginosa, by using the pL promoter of bacteriophage lambda inserted upstream of the coding sequence, pili which were indistinguishable from pili of M. bovis were produced.

Jennifer C Wilson - One of the best experts on this subject based on the ideXlab platform.

  • identification and characterisation of a biosynthetic locus for Moraxella bovis lipo oligosaccharide
    Carbohydrate Research, 2016
    Co-Authors: Isabelle Faglin, Jennifer C Wilson, Darren I Grice, Teresemarie Daal, S Eranda R A M Ratnayake, Sanjesh Singh, Ian R Peak
    Abstract:

    Moraxella bovis is a Gram-negative gammaproteobacterium and is one of the causative agents of infectious bovine keratoconjunctivitis. The structure of lipooligosaccharide (LOS) from strain Epp63 was recently elucidated. In the present study a genetic locus of seven encoding genes with high similarity to glycosyltransferases has been identified. Mutation of these putative glycosyltransferase genes resulted in M. bovis mutant bacteria that expressed truncated LOS structures. The structures of the oligosaccharide (OS) expressed by the mutant strains were elucidated and demonstrated the role of the glycosyltransferase enzymes in the LOS biosynthesis of M. bovis. The glycosyltransferase genes designated lgt1, lgt3, and lgt6 are highly similar to the genes in the related bacterium M. catarrhalis. In addition, there are syntenic similarities with the corresponding LOS biosynthesis locus in M. catarrhalis and other members of Moraxellaceae.

  • elucidation of the structure of the oligosaccharide from wild type Moraxella bovis epp63 lipooligosaccharide
    Carbohydrate Research, 2014
    Co-Authors: Cristina De Castro, Ian R Peak, Darren I Grice, Teresemarie Daal, Antonio Molinaro, Jennifer C Wilson
    Abstract:

    Abstract Moraxella bovis is a Gram-negative microorganism that causes Infectious Bovine Keratoconjunctivitis (IBK), colloquially known as ‘Pink eye’ in cattle worldwide. Lipopolysaccharides/lipooligosaccharides are the predominant glycans on the surface of Gram-negative microorganisms. Structural elucidation of the oligosaccharide structure of the rough phenotype of Moraxella bovis strain Epp63 was determined using GC–MS, methylation analysis, and NMR spectroscopy. The oligosaccharide is a branched structure that comprises 10 sugars in addition to KDO. The unusual features of this oligosaccharide include the fact that the oligosaccharide is devoid of heptose. The KDO residue is directly attached to a (→4,6)-branched glucose and additionally contains a terminal open chain acetal-linked N -acetylgalactosamine, (1 S )-Gal a NAc residue →4,6-linked to a sub-terminal galactose residue.

  • identification of a capsular polysaccharide from Moraxella bovis
    Carbohydrate Research, 2005
    Co-Authors: Jennifer C Wilson, Paul G Hitchen, Martin Frank, Ian R Peak, P Collins, Howard R Morris, Anne Dell, Darren I Grice
    Abstract:

    The bacterium Moraxella bovis is the causative agent of an economically important disease of cattle: Infectious Bovine Keratoconjunctivitis (IBK), otherwise known as pinkeye. Little is known regarding the structure of the carbohydrates produced by M. bovis. The structure of a capsular polysaccharide from M. bovis (strain Mb25) has been determined using NMR and MS analysis. From these data it is concluded that the polysaccharide is composed of the unmodified chondroitin disaccharide repeat unit.

Ian R Peak - One of the best experts on this subject based on the ideXlab platform.

  • identification and characterisation of a biosynthetic locus for Moraxella bovis lipo oligosaccharide
    Carbohydrate Research, 2016
    Co-Authors: Isabelle Faglin, Jennifer C Wilson, Darren I Grice, Teresemarie Daal, S Eranda R A M Ratnayake, Sanjesh Singh, Ian R Peak
    Abstract:

    Moraxella bovis is a Gram-negative gammaproteobacterium and is one of the causative agents of infectious bovine keratoconjunctivitis. The structure of lipooligosaccharide (LOS) from strain Epp63 was recently elucidated. In the present study a genetic locus of seven encoding genes with high similarity to glycosyltransferases has been identified. Mutation of these putative glycosyltransferase genes resulted in M. bovis mutant bacteria that expressed truncated LOS structures. The structures of the oligosaccharide (OS) expressed by the mutant strains were elucidated and demonstrated the role of the glycosyltransferase enzymes in the LOS biosynthesis of M. bovis. The glycosyltransferase genes designated lgt1, lgt3, and lgt6 are highly similar to the genes in the related bacterium M. catarrhalis. In addition, there are syntenic similarities with the corresponding LOS biosynthesis locus in M. catarrhalis and other members of Moraxellaceae.

  • elucidation of the structure of the oligosaccharide from wild type Moraxella bovis epp63 lipooligosaccharide
    Carbohydrate Research, 2014
    Co-Authors: Cristina De Castro, Ian R Peak, Darren I Grice, Teresemarie Daal, Antonio Molinaro, Jennifer C Wilson
    Abstract:

    Abstract Moraxella bovis is a Gram-negative microorganism that causes Infectious Bovine Keratoconjunctivitis (IBK), colloquially known as ‘Pink eye’ in cattle worldwide. Lipopolysaccharides/lipooligosaccharides are the predominant glycans on the surface of Gram-negative microorganisms. Structural elucidation of the oligosaccharide structure of the rough phenotype of Moraxella bovis strain Epp63 was determined using GC–MS, methylation analysis, and NMR spectroscopy. The oligosaccharide is a branched structure that comprises 10 sugars in addition to KDO. The unusual features of this oligosaccharide include the fact that the oligosaccharide is devoid of heptose. The KDO residue is directly attached to a (→4,6)-branched glucose and additionally contains a terminal open chain acetal-linked N -acetylgalactosamine, (1 S )-Gal a NAc residue →4,6-linked to a sub-terminal galactose residue.

  • identification of a capsular polysaccharide from Moraxella bovis
    Carbohydrate Research, 2005
    Co-Authors: Jennifer C Wilson, Paul G Hitchen, Martin Frank, Ian R Peak, P Collins, Howard R Morris, Anne Dell, Darren I Grice
    Abstract:

    The bacterium Moraxella bovis is the causative agent of an economically important disease of cattle: Infectious Bovine Keratoconjunctivitis (IBK), otherwise known as pinkeye. Little is known regarding the structure of the carbohydrates produced by M. bovis. The structure of a capsular polysaccharide from M. bovis (strain Mb25) has been determined using NMR and MS analysis. From these data it is concluded that the polysaccharide is composed of the unmodified chondroitin disaccharide repeat unit.

Shinji Takai - One of the best experts on this subject based on the ideXlab platform.

  • filamentous haemagglutinin like protein genes encoded on a plasmid of Moraxella bovis
    Veterinary Microbiology, 2006
    Co-Authors: Tsutomu Kakuda, Nopporn Sarataphan, Tetsuya Tanaka, Shinji Takai
    Abstract:

    The complete nucleotide sequence of a plasmid, pMBO-1, from Moraxella bovis strain Epp63 was determined. We identified 30 open reading frames (ORFs) encoded by the 44,215 bp molecule. Two large ORFs, flpA and flpB, encoding proteins with similarity to Bordetella pertussis filamentous haemagglutinin (FHA), were identified on the same plasmid. The gene for a specific accessory protein (Fap), which may play a role in the secretion of Flp protein, was also identified. Reverse transcriptase PCR analysis of total RNA isolated from M. bovis Epp63 indicated that the flpA, flpB, and fap genes are all transcribed. Southern blot analysis indicated that the flp and fap genes are present in other clinical isolates of geographically diverse M. bovis.

  • molecular cloning and characterization of a 79 kda iron repressible outer membrane protein of Moraxella bovis
    Fems Microbiology Letters, 2003
    Co-Authors: Tsutomu Kakuda, Daiki Oishi, Shiro Tsubaki, Shinji Takai
    Abstract:

    Moraxella bovis expresses an iron-repressible 79-kDa outer-membrane protein, IrpA. DNA and N-terminal amino acid sequence analysis indicate that IrpA is closely related to FrpB of Neisseria meningitidis, FetA of Neisseria gonorrhoeae and CopB of Moraxella catarrhalis. The results of manganese mutagenesis and a gel-shift assay suggested that the transcription of irpA is negatively regulated by the ferric uptake regulator. The insertion of an antibiotic resistance cassette into the irpA gene affected the strain’s ability to utilize bovine transferrin and lactoferrin. IrpA was detected in geographically diverse clinical isolates, and the antigenicity of IrpA was conserved in all the isolates tested. Therefore, IrpA may have potential as a candidate vaccine.

  • cloning and characterization of the fur gene from Moraxella bovis
    Microbiology and Immunology, 2003
    Co-Authors: Tsutomu Kakuda, Daiki Oishi, Shiro Tsubaki, Shinji Takai
    Abstract:

    A homologue of the ferric uptake regulator gene (fur) was isolated from Moraxella bovis by degenerate polymerase chain reaction and cloning. Fur protein of M. bovis exhibited 72.1% amino acid identity with Acinetobacter calcoaceticus Fur. Western blot analysis showed a decrease of Fur expression in response to sufficient-iron conditions compared with deficient-iron conditions. An electrophoretic mobility-shift assay indicated that Fur protein binds to DNA fragments containing a putative Fur-box derived from the upstream region of the M. bovis fur gene. Fur of M. bovis may regulate the expression of iron transport systems in response to iron limitation in the environment.