Biomedical subjects

M B Perry

Publications and source records attributed to M B Perry.

At least 109 records · Page 6Linked to original sources

PubMed1989

Structure of the lipopolysaccharide antigenic O-chain produced by Salmonella livingstone (O:6,7).

The lipopolysaccharide produced by Salmonella livingstone (O:6,7) was composed of an antigenic O-polysaccharide which was shown by composition, methylation analysis, and high resolution nuclear magnetic resonance studies to be a high molecular weight polymer containing D-glucose, 2-acetamido-2-deoxy-D-glucose, and D-mannose residues (1:1:4) composed in a repeating hexasaccharide unit having the structure: (formula; see text)

Antigens, Bacterial↗

PubMed1988

Structure of the capsular polymer of Actinobacillus pleuropneumoniae serotype 6.

The capsular polymer of Actinobacillus pleuropneumoniae serotype 6 (ATCC 33590) was investigated by methylation, dephosphorylation, partial hydrolysis, and 1H- and 13C-n.m.r. methods. It was found to be a high-molecular-weight polymer composed of triglycosylglycerol phosphate repeating-units joined through monophosphate diester linkages, and has the structure: (formula; see text).

Actinobacillus↗

PubMed1988

Application of high-resolution n.m.r. spectroscopy to the elucidation of the structure of the specific capsular polysaccharide of Streptococcus pneumoniae type 7F.

The specific capsular polysaccharide of Streptococcus pneumoniae type 7F (American type 51) is a high-molecular-weight neutral polymer composed of 2-acetamido-2-deoxy-D-galactose, 2-acetamido-2-deoxy-D-glucose, D-glucose, D-galactose, L-rhamnose, and 2-O-acetyl-L-rhamnose residues. N.m.r. spectroscopy (1H and 13C), in conjunction with composition and methylation analyses, and periodate oxidation data, showed the polysaccharide to be a branched polymer with a repeating heptasaccharide unit having the following structure. (formula; see text)

Acetylation↗

PubMed1988

Structural analysis of the specific capsular polysaccharide of Streptococcus pneumoniae type 45 (American type 72).

The specific capsular polysaccharide of Streptococcus pneumoniae type 45 (American type 72) was found to be a high molecular weight polymer composed of D-galactose, 2-acetamido-2-deoxy-D-galactose, 2-acetamido-2-deoxy-D-glucose, 2-acetamido-2-deoxy-L-fucose, L-rhamnose, glycerol, and phosphate (2:1:1:1:1:1:1). Partial hydrolysis, dephosphorylation, methylation analysis, periodate oxidation studies, and one- and two-dimensional 1H and 13C high-field nuclear magnetic resonance experiments showed the polysaccharide to be a branched polymer of a 1-phosphoglycerol-substituted hexasaccharide repeating unit having the structure: (formula; see text).

Carbohydrate Sequence↗

PubMed1988

Structure of the major lipopolysaccharide antigenic O-chain produced by Salmonella carrau (O:6, 14, 24).

Salmonella carrau, which belongs to group H (O:6, 14, 24) of the Kauffmann-White classification system, produced a major (90%) smooth lipopolysaccharide which by SDS-PAGE, glycose analysis, methylation, periodate oxidation, deamination, and 1H- and 13C-n.m.r. studies was shown to have an O-polysaccharide moiety composed of a repeating pentasaccharide having the structure: (formula: see text).

Antigens, Bacterial↗

PubMed1988

Structure of the O-antigen polysaccharide of Haemophilus pleuropneumoniae serotype 3 (ATCC 27090) lipopolysaccharide.

The structure of the O-antigen polysaccharide of Haemophilus pleuropneumoniae serotype 3 (ATCC 27090) S-type lipopolysaccharide was investigated by methylation analysis, partial hydrolysis, periodate oxidation, and 1H- and 13C-n.m.r. spectroscopy, and concluded to be composed of linear pentasaccharide repeating-units having the structure: [----3)-alpha-D-Glcp-(1----2)-beta-D-Galf-(1----6)-alpha-D-Galp-(1 ----6)- beta-D-Glcp-(1----3)-beta-D-Galf-(1----]n.

Antigens, Bacterial↗

PubMed1988

Rapid hydrophobic grid membrane filter-enzyme-labeled antibody procedure for identification and enumeration of Escherichia coli O157 in foods.

An O-antigen-specific monoclonal antibody, labeled by horseradish peroxidase-protein A, was used in a hydrophobic grid membrane filter-enzyme-labeled antibody method for rapid detection of Escherichia coli O157 in foods. The method yielded presumptive identification within 24 h and recovered, on average, 95% of E. coli O157:H7 artificially inoculated into comminuted beef, veal, pork, chicken giblets, and chicken carcass washings. In food samples from two outbreaks involving E. coli O157:H7, the organism was isolated at levels of up to 10(3)/g. The lower limit of sensitivity was 10 E. coli O157 per g of meat. Specific typing for E. coli O157:H7 can be achieved through staining with labeled H7 antiserum or tube agglutination.

Animals↗

PubMed1988

Characterization of Brucella polysaccharide B.

Polysaccharide B was extracted from Brucella melitensis 16M and from a rough strain of Brucella abortus 45/20 by autoclaving or trichloroacetic acid extraction of whole cells and by a new method involving mild leaching of cells. The material obtained by either of the established procedures was contaminated by O polysaccharide. The new leaching protocol eliminated this impurity and provided a pure glucan, which was regarded as polysaccharide B. This polysaccharide was found by high-performance liquid chromatography separations, chemical composition, methylation, and two-dimensional homo- and heteronuclear magnetic resonance experiments to be a family of nonreducing cyclic 1,2-linked polymers of beta-D-glucopyranosyl residues. The degree of polymerization varied between 17 and 24. Polysaccharide B was essentially identical to cyclic D-glucans produced by Rhizobia, Agrobacteria, and other bacterial species. Pure polysaccharide B did not precipitate with Brucella anti-A or anti-M serum and did not inhibit the serological reaction of Brucella A or M antigen with either bovine or murine monoclonal Brucella anti-A or anti-M serum. Previously described serological reactions of polysaccharide B preparations with Brucella anti-A and anti-M sera are related in this study to the presence in crude extracts of contaminants with the antigenic properties of Brucella lipopolysaccharide O polysaccharides.

Antigens, Bacterial↗

PubMed1988

Identification of Escherichia coli serotype O157 strains by using a monoclonal antibody.

The O157 antigenic determinant of Escherichia coli serotype O157:H7, an important bacterial pathogen, resides in the polysaccharide portion of its cellular lipopolysaccharide component which, from structural studies, was identified as a linear polymer of a repeating tetrasaccharide unit composed of D-glucose, L-fucose, 2-acetamido-2-deoxy-D-galactose, and 4-acetamido-4,6-dideoxy-D-mannose residues (1:1:1:1). Hybrid cells producing monoclonal antibodies against the E. coli O157 antigen were obtained by fusion of myeloma cells with lymphocytes from BALB/c mice immunized with killed E. coli O157:117 cells. Clones were selected for binding specificity with purified O polysaccharide. One monoclonal antibody used in direct slide agglutinations or in coagglutination reactions with Staphylococcus aureus Cowan 1 cells sensitized with the affinity column-purified antibody accurately detected all strains of E. coli O157 tested. This selected monoclonal antibody did not agglutinate E. coli strains such as E. coli O7 and E. coli O116 or other bacteria which are known to give positive agglutinations with conventional polyclonal E. coli antisera. These results indicate that the monoclonal antibody is a superior specific-typing reagent.

Agglutination Tests↗

PubMed1988

Structure of the antigenic O-polysaccharide of the lipopolysaccharide produced by Salmonella eimsbuttel.

The smooth lipopolysaccharide produced by Salmonella eimsbuttel, which had the O:6, O:7, and O:14 antigenic factors defined in the Kauffmann-White classification, was shown by sodium dodecyl sulfate-polyacrylamide gel electrophoresis analysis, composition analysis, methylation, periodate oxidation, deamination, and 1H and 13C nuclear magnetic resonance studies to contain a high molecular weight O-chain polysaccharide composed of D-mannose (four parts), D-glucose (one part), and 2-acetamido-2-deoxy-D-glucose (one part). It was a branched polymer of a repeating hexasaccharide unit having the structure (formula; see text).

Antigens, Bacterial↗

PubMed1988

Structure of the specific capsular polysaccharide of Streptococcus pneumoniae type 23F (American type 23).

The specific capsular polysaccharide of Streptococcus pneumoniae serotype 23F (American type 23) is composed of a repeating tetrasaccharide unit containing D-glucose (one part), D-galactose (one part), L-rhamnose (two parts), glycerol (one part), and phosphate (one part). By composition analysis, optical rotation, partial hydrolysis, periodate oxidation, methylation, and high-resolution 1H and 13C nuclear magnetic resonance studies, the elucidated unambiguous structure was in agreement with our earlier proposal but is at variance with structures proposed later by other authors. The structure of the type 23F pneumococcal polysaccharide is (formula; see text).

Chromatography, Gas↗

PubMed1988

The structures of the two lipopolysaccharide O-chains produced by Salmonella boecker.

Salmonella boecker, which belongs to group 0:6, 14(H) and shows the antigenic factors 6, 14, [1], and [25], defined by the Kauffmann-White system, produces two lipopolysaccharides differing from each other in the structures of their 0-poly-saccharide moieties. By glycose composition, partial hydrolysis, nitrous acid deamination, methylation, optical rotation, and 1H and 13C nuclear magnetic resonance studies, the O-polysaccharides were demonstrated to be high-molecular-weight polymers (I and II) composed of either structurally related repeating tetrasaccharide or repeating pentasaccharide units having the structures and (table; see text).

Carbohydrate Sequence↗

PubMed1987

Structure of the capsular polysaccharide of Haemophilus pleuropneumoniae serotype 5.

The capsular polysaccharide of Haemophilus (Actinobacillus) pleuropneumoniae serotype 5 (ATCC 33377) was found to be a linear type polysaccharide of a repeating disaccharide unit composed of 2-acetamido-2-deoxy-D-glucose and 3-deoxy-D-manno-2-octulosonic acid (dOclA). By composition analysis, methylation, partial hydrolysis and 1H and 13C nuclear magnetic resonance studies, it was concluded that the capsular polysaccharide is a high-molecular-mass unbranched polymer having the structure: [6)-alpha-D-GlcNAcp-(1-5)-beta-dOclAp-(2]n.

Carbohydrates↗

PubMed1987

Structural elucidation of the Brucella melitensis M antigen by high-resolution NMR at 500 MHz.

The Brucella M antigen from the species type strain Brucella melitensis 16M has been identified as a component of the cell wall lipopolysaccharide (LPS). O polysaccharide liberated from this LPS by mild acid hydrolysis exhibited M activity in serological tests and was shown to be a homopolymer of 4-formamido-4,6-dideoxy-alpha-D-mannopyranosyl residues arranged in an oligosaccharide repeating unit as judged by sodium dodecyl sulfate-polyacrylamide gel electrophoresis of the native lipopolysaccharide. Structural analysis of the O polysaccharide by NMR methods was difficult due to apparent microheterogeneity of the repeating unit, which was in fact caused by the presence of rotational isomers of the N-formyl moiety. This problem was resolved by chemical modification of the polysaccharide to its amino and N-acetyl derivatives, the 500-MHz 1H and 125-MHz 13C NMR spectra of which could be analyzed in terms of a unique structure through application of pH-dependent beta-shifts and two-dimensional techniques that included COSY, relayed COSY, and NOESY experiments together with heteronuclear C/H shift correlation spectroscopy. On the basis of these experiments and supported by methylation and periodate oxidation data, the structure of the M polysaccharide was determined as a linear polymer of unbranched pentasaccharide repeating units consisting of four 1,2-linked and one 1,3-linked 4,6-dideoxy-4-formamido-alpha-D-mannopyranosyl residues. The marked structural similarity of the M antigen and the A antigen, which is known to be a 1,2-linked homopolysaccharide of 4,6-dideoxy-4-formamido-alpha-D-mannopyranosyl units, accounts for cross-serological reactions of the two and the long-standing confusion surrounding the nature of their antigenic determinants. Structural and serological considerations in conjuction with the sodium dodecyl sulfate banding pattern of Brucella A LPS suggest that its biosynthesis differs appreciably from that of the M antigen, which appears to be synthesized by regulated assembly of preformed oligosaccharide repeating units. Temperature, lysogenic phage may be responsible for such biosynthetic and structural variations.

Antigens, Bacterial↗

PubMed1987

The structure of the lipopolysaccharide O-chain (M antigen) and polysaccharide B produced by Brucella melitensis 16M.

The surface M antigen of Brucella species has been identified as the lipopolysaccharide O-polysaccharide component composed of a repeating pentasaccharide unit containing a sequence of one 1,3- and four 1,2-linked, 4,6-dideoxy-4-formamido-alpha-D-mannopyranosyl units. A neutral polysaccharide produced by Brucella species and referred to as polysaccharide B (poly B) has been identified as a family of circular 1,2-linked polymers of beta-D-glucopyranosyl units ranging in ring size from 17 to 24 glucosyl units.

Antigens, Bacterial↗

PubMed1987

Electrophoretic and immunochemical study of the lipopolysaccharides produced by chemostat-grown Escherichia coli O157.

Two chemically different O-polysaccharides, a low molecular mass form of LPS and core LPS produced by chemostat-grown E. coli O157, were analysed by SDS-PAGE, silver staining and immunoblotting. The reactivities of the different O-polysaccharides with antisera prepared against E. coli O157 grown in batch culture, Salmonella O30 or Brucella abortus were very similar, showing that the O-polysaccharides share at least some antigenic determinants. The reactions of the low molecular mass LPS with the antisera indicated it was semi-rough LPS having one repeat unit of the O-polysaccharide attached to core LPS.

Electrophoresis, Polyacrylamide Gel↗

PubMed1987

Alterations in lipopolysaccharide produced by chemostat-grown Escherichia coli O157:H7 as a function of growth rate and growth-limiting nutrient.

Escherichia coli O157:H7 was grown in chemostats as continuous cultures at different controlled growth rates and under different nutrient limitations to determine the effects on lipopolysaccharide (LPS) structure. LPS from whole cells and extracted using the hot aqueous phenol method was examined by sodium dodecyl sulfate--polyacrylamide gel electrophoresis (SDS-PAGE) and by gel filtration after hydrolysis with acetic acid. At low growth rates under glucose limitation (D = 0.1 h-1, doubling time (td), approx. 416 min; or D = 0.4 h-1, td, approx. 104 min), E. coli O157 produced high molecular weight LPS identical to that previously characterized from cells grown in batch culture. At a high growth rate (D = 0.8 h-1, td, approx. 52 min), the ratio of high molecular weight LPS to low molecular weight LPS produced greatly decreased. A small amount of high molecular weight LPS, containing O-polysaccharide which lacked amino sugars, and which thus was chemically different from that previously characterized, was produced by the cells at high growth rates. The predominant form of LPS from these cells was of slightly higher molecular weight than rough LPS, probably S-R LPS, and it consistently formed aggregates on SDS-PAGE. This form of LPS was also predominant when E. coli O157 was grown under Mg2+ limitation at an intermediate growth rate (D = 0.4 h-1, td, approx. 104 min).

Chromatography, Gel↗

PubMed1987

Identification of the A and M antigens of Brucella as the O-polysaccharides of smooth lipopolysaccharides.

Rabbit antisera, cross-absorbed serotype-specific for the Brucella A and M antigens, precipitated respectively the smooth lipopolysaccharides from B. abortus 1119-3 and B. melitensis 16M. The antigenic A and M activity of these lipopolysaccharides was shown to reside within the O-chain region of the smooth lipopolysaccharides by inhibition experiments. Homologous O-polysaccharides showed the highest inhibitory activity in ELISA, although both the A and M antigens were active as heterologous inhibitors, showing that the antigenic determinants of the classical A and M antigens are therefore within the respective O-polysaccharide structures. Their cross-serological activity may be explained in terms of the distinct but related chemical structures of these polysaccharides.

Antigens, Bacterial↗