scholarly journals Isolation, chemical composition, and molecular size of extracellular type II and type Ia polysaccharides of group B streptococci.

1983 ◽  
Vol 41 (2) ◽  
pp. 527-534 ◽  
Author(s):  
B J De Cueninck ◽  
T F Greber ◽  
T K Eisenstein ◽  
R M Swenson ◽  
G D Shockman
Keyword(s):  
Chemical Composition ◽  
Molecular Size ◽  
Type Ii ◽  
Group B Streptococci ◽  
Type Ia ◽  
Group B

scholarly journals Heterogeneity of penicillin-non-susceptible group B streptococci isolated from a single patient in Germany

2019 ◽  
Vol 75 (2) ◽  
pp. 296-299 ◽  
Author(s):  
Mark van der Linden ◽  
Rafael Mamede ◽  
Natascha Levina ◽  
Peter Helwig ◽  
Pedro Vila-Cerqueira ◽  
...  
Keyword(s):  
High Throughput Sequencing ◽  
Genomic Analysis ◽  
Amino Acid Sequences ◽  
Capsular Type ◽  
Group B Streptococci ◽  
The Us ◽  
Type Ia ◽  
The Usa ◽  
Group B ◽  
Host Evolution

Abstract Objectives Streptococcus agalactiae [group B streptococci (GBS)] have been considered uniformly susceptible to penicillin. However, increasing reports from Asia and North America are documenting penicillin-non-susceptible GBS (PRGBS) with mutations in pbp genes. Here we report, to the best of our knowledge, the first two PRGBS isolates recovered in Europe (AC-13238-1 and AC-13238-2), isolated from the same patient. Methods Two different colony morphologies of GBS were noted from a surgical abscess drainage sample. Both were serotyped and antimicrobial susceptibility testing was performed by different methodologies. High-throughput sequencing was done to compare the isolates at the genomic level, to identify their capsular type and ST, to evaluate mutations in the pbp genes and to compare the isolates with the genomes of other PRGBS isolates sharing the same serotype and ST. Results Isolates AC-13238-1 and AC-13238-2 presented MICs above the EUCAST and CLSI breakpoints for penicillin susceptibility. Both shared the capsular type Ia operon and ST23. Genomic analysis uncovered differences between the two isolates in seven genes, including altered pbp genes. Deduced amino acid sequences revealed critical substitutions in PBP2X in both isolates. Comparison with serotype Ia clonal complex 23 PRGBS from the USA reinforced the similarity between AC-13238-1 and AC-13238-2, and their divergence from the US strains. Conclusions Our results support the in-host evolution of β-lactam-resistant GBS, with two PRGBS variants being isolated from one patient.

Cross protection in mice with the Smith diffuse strain of Staphylococcus aureus versus a type Ia strain of group B streptococci

1982 ◽  
Vol 28 (7) ◽  
pp. 726-732 ◽  
Author(s):  
Yoshitoshi Ichiman ◽  
Kosaku Yoshida
Keyword(s):  
Staphylococcus Aureus ◽  
Cell Surface ◽  
Active Immunization ◽  
Cell Vaccine ◽  
Group B Streptococci ◽  
Type Ia ◽  
Whole Cell Vaccine ◽  
Surface Polysaccharides ◽  
Surface Polysaccharide ◽  
Group B

Active immunization of mice with whole cell vaccine or cell surface polysaccharide from either the Smith diffuse strain of Staphylococcus aureus or SS-615 (type Ia of group B streptococci) protected against challenge by either the homologous or heterologous strains. In the peritoneal cavity of mice immunized with either of these organisms rapid phagocytosis and reduction of the viable cells was observed at 6 h after the challenge. Cell surface polysaccharides extracted from strains Smith diffuse and SS-615, both prepared by the same procedure as that of the Smith surface antigen, were capable of absorbing the protective antibody in rabbit hyperimmune sera prepared with homologous or heterologous strains.

The Role of Complement and Antibody in Opsonophagocytosis of Type II Group B Streptococci

1986 ◽  
Vol 154 (1) ◽  
pp. 47-54 ◽  
Author(s):  
C. J. Baker ◽  
B. J. Webb ◽  
D. L. Kasper ◽  
M. S. Edwards
Keyword(s):  
Type Ii ◽  
Group B Streptococci ◽  
Group B

scholarly journals Lethal synergism induced in mice by influenza type A virus and type Ia group B streptococci.

1983 ◽  
Vol 41 (2) ◽  
pp. 618-623 ◽  
Author(s):  
W T Jones ◽  
J H Menna ◽  
D E Wennerstrom
Keyword(s):  
Type A ◽  
Group B Streptococci ◽  
Influenza Type ◽  
Type Ia ◽  
Group B

scholarly journals Group B Streptococcal Type II and III Conjugate Vaccines: Physicochemical Properties That Influence Immunogenicity

2006 ◽  
Vol 13 (8) ◽  
pp. 936-943 ◽  
Author(s):  
Francis Michon ◽  
Catherine Uitz ◽  
Arun Sarkar ◽  
Anello J. D'Ambra ◽  
Maryline Laude-Sharp ◽  
...  
Keyword(s):  
Sialic Acid ◽  
Reductive Amination ◽  
High Titer ◽  
Type Ii ◽  
Group B Streptococci ◽  
End Groups ◽  
Group B ◽  
Aldehyde Groups ◽  
Opsonophagocytic Killing ◽  
Acid Labile

ABSTRACT Recent efforts toward developing vaccines against group B streptococci (GBS) have focused on increasing the immunogenicity of GBS polysaccharides by conjugation to carrier proteins. However, partial depolymerization of GBS polysaccharides for the production of vaccines is a difficult task because of their acid-labile, antigenically critical sialic acids. Here we report a method for the partial depolymerization of type II and III polysaccharides by mild deaminative cleavage to antigenic fragments with reducing-terminal 2,5-anhydro-d-mannose residues. Through the free aldehydes of their newly formed end groups, the fragments were conjugated to tetanus toxoid by reductive amination. The resulting conjugates stimulated the production in animals of high-titer type II- and III-specific antibodies which induced opsonophagocytic killing of type II and III strains of group B streptococci. For the type II conjugates, immunogenicity increased as oligosaccharide size decreased, whereas for type III conjugates, the size of the oligosaccharides did not significantly influence immunogenicity. When oligosaccharides of defined size were conjugated through sialic acid residues, the resulting cross-linkages were shown to affect immunogenicity. When oligosaccharides were conjugated through terminal aldehyde groups generated by deamination, modification of the exocyclic chain of sialic acid did not influence immunogenicity.

scholarly journals TWO SEROLOGICAL TYPES OF GROUP B HEMOLYTIC STREPTOCOCCI WITH RELATED, BUT NOT IDENTICAL, TYPE-SPECIFIC SUBSTANCES

1938 ◽  
Vol 67 (1) ◽  
pp. 25-40 ◽  
Author(s):  
Rebecca C. Lancefield
Keyword(s):  
Group B Streptococci ◽  
Passive Protection ◽  
Cross Reactions ◽  
Precipitin Reaction ◽  
Specific Substance ◽  
Type Ia ◽  
Preliminary Study ◽  
The Cross ◽  
Group B ◽  
Identical Type

1. Among group B hemolytic streptococci one serological type previously described as homogeneous has been shown, instead, to contain two closely related types, distinguishable by reciprocal absorption experiments. These streptococci are designated Types Ia and Ib. 2. Homologous organisms in each case absorb all antibodies from their respective antisera, while organisms of the heterologous related type absorb only the antibody responsible for the cross reactions. Group B streptococci of other types do not absorb the antibodies responsible for the cross reactions between these two related types. The precipitin reaction and passive protection tests in mice were employed in this analysis. 3. The type-specific substance of Type Ia is a polysaccharide. Preliminary study indicates that this is also true of Type Ib. While no data are available concerning the chemical relationships of these substances, it seems probable that the two types elaborate polysaccharides, related chemically as well as serologically.

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