Structure determination ofStreptococcus suisserotype 14 capsular polysaccharide

2013 ◽  
Vol 91 (2) ◽  
pp. 49-58 ◽  
Author(s):  
Marie-Rose Van Calsteren ◽  
Fleur Gagnon ◽  
Cynthia Calzas ◽  
Guillaume Goyette-Desjardins ◽  
Masatoshi Okura ◽  
...  
Keyword(s):  
Sialic Acid ◽  
Capsular Polysaccharide ◽  
Group B Streptococcus ◽  
Periodate Oxidation ◽  
Side Chain ◽  
Chemically Modified ◽  
Type Ia ◽  
Group B ◽  
Suis Serotype ◽  
Mild Acid

The capsular polysaccharide (CPS) of Streptococcus suis serotype 14 was purified, chemically modified, and characterized. Sugar and absolute configuration analyses gave the following CPS composition: d-Gal, 3; d-Glc, 1; d-GlcNAc, 1; d-Neu5Ac, 1. The Sambucus nigra lectin, which recognizes the Neu5Ac(α2–6)Gal/GalNAc sequence, showed binding to the native CPS. Sialic acid was found to be terminal, and the CPS was quantitatively desialylated by mild acid hydrolysis. It was also submitted to periodate oxidation followed by borohydride reduction and Smith degradation. Sugar and methylation analyses,1H and13C nuclear magnetic resonance, and mass spectrometry of the native CPS or of its specifically modified products allowed to determine the repeating unit sequence: [6)[Neu5Ac(α2–6)Gal(β1–4)GlcNAc(β1–3)]Gal(β1–3)Gal(β1–4)Glc(β1–]n. S. suis serotype 14 CPS has an identical sialic acid-containing side chain as serotype 2 CPS, but differs by the absence of rhamnose in its composition. The same side chain is also present in group B Streptococcus type Ia CPS, except that in the latter sialic acid is 2,3- rather than 2,6-linked to the following galactose. A correlation between the S. suis CPS sequence and genes of the serotype 14 cps locus encoding putative glycosyltransferases and polymerase responsible for the biosynthesis of the repeating unit is proposed.

Structure determination ofStreptococcus suisserotype 2 capsular polysaccharide

2010 ◽  
Vol 88 (3) ◽  
pp. 513-525 ◽  
Author(s):  
Marie-Rose Van Calsteren ◽  
Fleur Gagnon ◽  
Sonia Lacouture ◽  
Nahuel Fittipaldi ◽  
Marcello Gottschalk
Keyword(s):  
Sialic Acid ◽  
Capsular Polysaccharide ◽  
Group B Streptococcus ◽  
Periodate Oxidation ◽  
Methylation Analysis ◽  
Mild Acid Hydrolysis ◽  
Chemically Modified ◽  
Group B ◽  
Suis Serotype ◽  
Mild Acid

The capsular polysaccharide (CPS) of Streptococcus suis serotype 2 was isolated, purified, chemically modified, and characterized. Sugar and absolute configuration analyses of the CPS gave the following composition: d-Gal, 3; d-Glc, 1; d-GlcNAc, 1; d-Neu5Ac, 1; l-Rha, 1. Sialic acid was found to be terminal, and the CPS was quantitatively desialylated by mild acid hydrolysis. The CPS was also submitted to periodate oxidation followed by borohydride reduction and Smith degradation. Sugar and methylation analysis,1H and13C nuclear magnetic resonance, and mass spectrometry of the native CPS or of its specifically modified products allowed to determine the repeating unit sequence: [4)[Neu5Ac(α2–6)Gal(β1–4)GlcNAc(β1–3)]Gal(β1–4)[Gal(α1–3)]Rha(β1–4)Glc(β1-]n. The backbone sequence was found to be identical to that of Streptococcus agalactiae or group B Streptococcus (GBS) type VIII and Streptococcus pneumoniae type 23F. The S. suis CPS shares the sequence Neu5Ac-Gal-GlcNAc-Gal in common with GBS types Ia, Ib, II, III, and IV CPSs but differs from them by the presence of rhamnose and the fact that sialic acid is 2,6- rather than 2,3-linked to the following Gal. A correlation between the S. suis CPS sequence and genes of the serotype 2 cps locus encoding putative enzymes responsible for the biosynthesis of the repeating unit was tentatively established.

scholarly journals NeuA Sialic Acid O-Acetylesterase Activity Modulates O-Acetylation of Capsular Polysaccharide in Group B Streptococcus

2007 ◽  
Vol 282 (38) ◽  
pp. 27562-27571 ◽  
Author(s):  
Amanda L. Lewis ◽  
Hongzhi Cao ◽  
Silpa K. Patel ◽  
Sandra Diaz ◽  
Wesley Ryan ◽  
...  
Keyword(s):  
Sialic Acid ◽  
Capsular Polysaccharide ◽  
Group B Streptococcus ◽  
Site Directed Mutagenesis ◽  
Synthetase Activity ◽  
Bacterial Surface ◽  
Acetylneuraminic Acid ◽  
Single Polypeptide ◽  
Group B

Group B Streptococcus (GBS) is a common cause of neonatal sepsis and meningitis. A major GBS virulence determinant is its sialic acid (Sia)-capped capsular polysaccharide. Recently, we discovered the presence and genetic basis of capsular Sia O-acetylation in GBS. We now characterize a GBS Sia O-acetylesterase that modulates the degree of GBS surface O-acetylation. The GBS Sia O-acetylesterase operates cooperatively with the GBS CMP-Sia synthetase, both part of a single polypeptide encoded by the neuA gene. NeuA de-O-acetylation of free 9-O-acetyl-N-acetylneuraminic acid (Neu5,9Ac2) was enhanced by CTP and Mg2+, the substrate and co-factor, respectively, of the N-terminal GBS CMP-Sia synthetase domain. In contrast, the homologous bifunctional NeuA esterase from Escherichia coli K1 did not display cofactor dependence. Further analyses showed that in vitro, GBS NeuA can operate via two alternate enzymatic pathways: de-O-acetylation of Neu5,9Ac2 followed by CMP activation of Neu5Ac or activation of Neu5,9Ac2 followed by de-O-acetylation of CMP-Neu5,9Ac2. Consistent with in vitro esterase assays, genetic deletion of GBS neuA led to accumulation of intracellular O-acetylated Sias, and overexpression of GBS NeuA reduced O-acetylation of Sias on the bacterial surface. Site-directed mutagenesis of conserved asparagine residue 301 abolished esterase activity but preserved CMP-Sia synthetase activity, as evidenced by hyper-O-acetylation of capsular polysaccharide Sias on GBS expressing only the N301A NeuA allele. These studies demonstrate a novel mechanism regulating the extent of capsular Sia O-acetylation in intact bacteria and provide a genetic strategy for manipulating GBS O-acetylation in order to explore the role of this modification in GBS pathogenesis and immunogenicity.

scholarly journals Chemical Synthesis of the Repeating Unit of Type Ia Group B Streptococcus Capsular Polysaccharide

2015 ◽  
Vol 17 (5) ◽  
pp. 1102-1105 ◽  
Author(s):  
Prolay K. Mondal ◽  
Guochao Liao ◽  
Mohabul A. Mondal ◽  
Zhongwu Guo
Keyword(s):  
Chemical Synthesis ◽  
Capsular Polysaccharide ◽  
Group B Streptococcus ◽  
Type Ia ◽  
Group B

scholarly journals Regulation of Cell Component Production by Growth Rate in the Group B Streptococcus

1999 ◽  
Vol 181 (17) ◽  
pp. 5389-5394 ◽  
Author(s):  
Robin A. Ross ◽  
Lawrence C. Madoff ◽  
Lawrence C. Paoletti
Keyword(s):  
Growth Rate ◽  
Alkaline Phosphatase ◽  
Capsular Polysaccharide ◽  
Group B Streptococcus ◽  
Dry Weight ◽  
C Protein ◽  
Rate Regulation ◽  
Type Ia ◽  
Cell Components ◽  
Group B

ABSTRACT Group B Streptococcus (GBS) is the leading cause of bacterial sepsis and meningitis among neonates. While the capsular polysaccharide (CPS) is an important virulence factor of GBS, other cell surface components, such as C proteins, may also play a role in GBS disease. CPS production by GBS type III strain M781 was greater when cells were held at a fast (1.4-h mass-doubling time [td ]) than at a slow (11-htd ) rate of growth. To further investigate growth rate regulation of CPS production and to investigate production of other cell components, different serotypes and strains of GBS were grown in continuous culture in a semidefined and a complex medium. Samples were obtained after at least five generations at the selected growth rate. Cells and cell-free supernatants were processed immediately, and results from all assays were normalized for cell dry weight. All serotypes (Ia, Ib, and III) and strains (one or two strains per serotype) tested produced at least 3.6-fold more CPS at atd of 1.4 h than at atd of 11 h. Production of beta C protein by GBS type Ia strain A909 and type Ib strain H36B was also shown to increase at least 5.5-fold with increased growth rate (production at atd of 1.4 h versus 11 h). The production of alpha C protein by the same strains did not significantly change with increased growth rate. The effect of growth rate on other cell components was also investigated. Production of group B antigen did not change with growth rate, while alkaline phosphatase decreased with increased growth rate. Both CAMP factor and beta-hemolysin production increased fourfold with increased growth rate. Growth rate regulation is specific for select cell components in GBS, including beta C protein, alkaline phosphatase, beta-hemolysin, and CPS production.

Construction of multivalent sialyl Lex from the type Ia group B Streptococcus capsular polysaccharide

2001 ◽  
Vol 332 (3) ◽  
pp. 249-255 ◽  
Author(s):  
Wei Zou ◽  
JianJun Li ◽  
Suzon Larocque ◽  
Harold J Jennings
Keyword(s):  
Capsular Polysaccharide ◽  
Group B Streptococcus ◽  
Sialyl Lex ◽  
Type Ia ◽  
Group B

scholarly journals Immunodeterminant specificity of human immunity to type III group B streptococcus.

1979 ◽  
Vol 149 (2) ◽  
pp. 327-339 ◽  
Author(s):  
D L Kasper ◽  
C J Baker ◽  
R S Baltimore ◽  
J H Crabb ◽  
G Schiffman ◽  
...  
Keyword(s):  
Sialic Acid ◽  
Capsular Polysaccharide ◽  
Group B Streptococcus ◽  
Core Antigen ◽  
Opsonic Activity ◽  
Type Iii ◽  
The Core ◽  
Native Antigen ◽  
Group B ◽  
Native Group

The type III polysaccharides of group B Streptococcus in its native state chemically consists of glucose, galactose, glucosamine, and sialic acid. The core of this polysaccharide lacks sialic acid and precipitates with type III antiserum to give a partial identity with the precipitate between the native antigen and this serum. The core determinant is immunochemically similar to the capsular polysaccharide of type XIV Streptococcus pneumoniae, while the native type III group B streptococcal polysaccharide does not cross-react with type XIV pneumococcal antiserum. In human sera, it is antibody directed to the native antigen which correlates very highly with opsonic immunity (r = 0.94) while a poorer correlation exists between antibody to the core antigen and opsonins (r = 0.51 P less than 0.001). In natural infections, as association exists between low levels of maternal antibody to the native antigen and risk of disease in the infant. This association is not true for antibody to the core structure, where both infected infants and their mothers have much higher levels of antibody to the core than the native antigens. Infected infants are also more likely to respond to infection by developing antibody to the native antigen. Immunization of 12 adults with multivalent pneumococcal polysaccharide induced significantly better antibody response to the core antigen than to the native, and this vaccine induced opsonic activity in only one recipient. Immunization of adults with type III group B streptococcal antigens induced antibody to the native determinant which correlated with opsonic activity. Therefore, it would appear that native group B streptococcal polysaccharides will provide the best candidate antigens for immunization.

scholarly journals Identification of Group B Streptococcus Capsule Type by Use of a Dual Phenotypic/Genotypic Assay

2017 ◽  
Vol 55 (9) ◽  
pp. 2637-2650 ◽  
Author(s):  
Areej Alhhazmi ◽  
Armaan Pandey ◽  
Gregory J. Tyrrell
Keyword(s):  
Sialic Acid ◽  
Large Scale ◽  
Capsular Polysaccharide ◽  
Group B Streptococcus ◽  
Epidemiological Studies ◽  
Dot Blot ◽  
Content Type ◽  
Dot Blot Assay ◽  
Important Virulence Factor ◽  
Group B

ABSTRACTThe group B streptococcus (GBS) capsular polysaccharide (CPS) is an important virulence factor which is also used for GBS typing. There are 10 CPS types (Ia, Ib, and II to IX). GBS that do not phenotypically type are considered nontypeable. All genes required for CPS synthesis are found on the GBScpsoperon, which contains a highly variable CPS-determining region (cpsG-cpsK). The objective of this study was development of an assay to detect sialic acid on the GBS cell surface, followed by a genotypic PCR CPS typing assay. Sialic acid is located at the terminal end of the side chain of all known GBS CPS types. Sialic acid can be bound to commercially available lectins such as slugLimax flavuslectin. BiotinylatedL. flavus-streptavidin-peroxidase complex was used in an enzyme immunoassay and dot blot assay to detect sialic acid. This was followed by a PCR typing scheme that was developed to target the serotype-determining region of thecpslocus for Ia, Ib, and II to IX. Sialic acid from the CPS types Ia, Ib, and II to IX was detectable on the GBS cell surfaces of all previously identified CPS-typed GBS strains assayed. This was followed by the real-time PCR typing assay which successfully identified CPS Ia, Ib, and II to IX types. The combination of phenotypic and genotypic assays provides an accurate tool for detection of CPS expression and assignment of CPS typing. These assays have the potential to be used for CPS typing in large-scale epidemiological studies.

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