Electron microscopic visualization of polysaccharide capsules on whole cell mounts of group B streptococci

1993 ◽  
Vol 24 (5) ◽  
pp. 455-456
Author(s):  
Barry M. Gray ◽  
Elizabeth W. Cooney
Keyword(s):  
Group B Streptococci ◽  
Electron Microscopic ◽  
Whole Cell ◽  
Group B ◽  
Polysaccharide Capsules

scholarly journals Putative Novel Surface-Exposed Streptococcus agalactiae Protein Frequently Expressed by the Group B Streptococcus from Zimbabwe

2009 ◽  
Vol 16 (9) ◽  
pp. 1302-1308 ◽  
Author(s):  
Rooyen T. Mavenyengwa ◽  
Johan A. Maeland ◽  
Sylvester R. Moyo
Keyword(s):  
Rabbit Antiserum ◽  
Periodate Oxidation ◽  
Cross Reactivity ◽  
Enzyme Linked Immunosorbent Assay ◽  
Protein Antigens ◽  
Group B Streptococci ◽  
Phenotypic Marker ◽  
Whole Cell ◽  
Strain Collection ◽  
Group B

ABSTRACTGroup B streptococci (GBS) express a variety of surface-exposed and strain-variable proteins which function as phenotypic markers and as antigens which are able to induce protective immunity in experimental settings. Among these proteins, the chimeric and immunologically cross-reacting alpha-like proteins are particularly important. Another protein, R3, which has been less well studied, occurred at a frequency of 21.5% in GBS from Zimbabwe and, notably, occurred in serotype V strains at a frequency of 75.9%. Working with rabbit antiserum raised against the R3 reference strain ATCC 49447 (strain 10/84; serotype V/R3) to detect the expression of the R3 protein, we recorded findings which suggested that strain 10/84 expressed a strain-variable protein antigen, in addition to R3. The antigen was detected by various enzyme-linked immunosorbent assay-based tests by using acid extract antigens or GBS whole-cell coats and by whole-cell-based Western blotting. We named the putative novel antigen the Z antigen. The Z antigen was a high-molecular-mass antigen that was susceptible to degradation by pepsin and trypsin but that was resistant tom-periodate oxidation and failed to show immunological cross-reactivity with any of a variety of other GBS protein antigens. The Z antigen was expressed by 33/121 (27.2%) of strains of a Zimbabwean GBS strain collection and by 64.2% and 72.4% of the type Ib and type V strains, respectively, and was occasionally expressed by GBS of other capsular serotypes. Thus, the putative novel GBS protein named Z showed distinct capsular antigen associations and presented as an important phenotypic marker in GBS from Zimbabwe. It may be an important antigen in GBS from larger areas of southern Africa. Its prevalence in GBS from Western countries is not known.

Susceptibility to Six Antibiotics of Group B Streptococci Isolated from Cerebrospinal Fluid

1985 ◽  
Vol 17 (2) ◽  
pp. 191-193
Author(s):  
Chris Mulder ◽  
Pieter Bol ◽  
Arjan Nabbe ◽  
Bob Zanen
Keyword(s):  
Cerebrospinal Fluid ◽  
Group B Streptococci ◽  
Group B

scholarly journals Influence of group B streptococci on piglet pulmonary artery response to bradykinin

1999 ◽  
Vol 86 (1) ◽  
pp. 61-65 ◽  
Author(s):  
Richard M. Whitehurst ◽  
Rachel Laskey ◽  
Ronald N. Goldberg ◽  
Donald Herbert ◽  
Cornelius Van Breemen
Keyword(s):  
Pulmonary Artery ◽  
Contractile Response ◽  
Isometric Force ◽  
Control Group ◽  
Relaxed Controls ◽  
Vascular Response ◽  
Group B Streptococci ◽  
Resting Tension ◽  
Neonatal Group ◽  
Group B

To study whether a sepsis-induced increase in des-Arg9-bradykinin (des-Arg9-BK) and bradykinin (BK) B1-receptor activity participates in the observed increase in pulmonary vascular resistance in neonatal group B streptococcal sepsis (GBS), isometric force bioassays of pulmonary artery (PA) rings were studied, after 4-h exposure to either Krebs or GBS, by using the following protocols: 1) BK dose-response curve, 2) vascular response to BK with N G-nitro-l-arginine methyl ester (l-NAME), and 3) response to des-Arg9-BK (BK metabolite and B1 agonist). PA rings exposed to BK resulted in contraction in the GBS group and a decrease in resting tension in the Control group ( P = 0.034) at a concentration of 10−5 M. GBS-treated PA rings contracted more to des-Arg9-BK than did Controls ( P < 0.001). BK (10−6 M) relaxed preconstricted PA rings incubated in GBS less than BK relaxed Controls ( P < 0.001), and preincubation withl-NAME decreased relaxation in both. These results suggest that GBS decreased endothelium-dependent BK relaxation and increased contractile response to des-Arg9-BK. We speculate that this occurs secondary to upregulation of B1 receptors reflected by B1-agonist-mediated PA contraction.

NEONATAL OSTEOMYELITIS AND MENINGITIS CAUSED BY GROUP B STREPTOCOCCI

1977 ◽  
Vol 2 (15) ◽  
pp. 500-501 ◽  
Author(s):  
Leslie R. Ashdown ◽  
P. H. Hewson ◽  
S. K. Suleman
Keyword(s):  
Group B Streptococci ◽  
Group B

scholarly journals Trends in molecular characteristics and antimicrobial resistance of group B streptococci: a multicenter study in Serbia, 2015–2020

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Dusan Kekic ◽  
Ina Gajic ◽  
Natasa Opavski ◽  
Milan Kojic ◽  
Goran Vukotic ◽  
...  
Keyword(s):  
Antimicrobial Resistance ◽  
Late Onset ◽  
Group B Streptococcus ◽  
Neonatal Morbidity ◽  
Disease Rate ◽  
Molecular Characteristics ◽  
Group B Streptococci ◽  
Live Births ◽  
Invasive Infections ◽  
Group B

AbstractGroup B Streptococcus (GBS) is a major cause of neonatal morbidity and mortality. Serbia has not fully implemented preventive measures against GBS neonatal diseases. Therefore, we aimed to assess the maternal GBS colonisation and invasive neonatal disease rate, to reveal the trends of antimicrobial resistance and serotype distribution of GBS from various patient groups. Randomly selected non-invasive (n = 991) and all invasive GBS (n = 80) collected throughout Serbia from 2015 to 2020 were tested for antimicrobial susceptibility, capsular typing, and hvgA detection. Overall, 877/5621 (15.6%) pregnant women were colonised with GBS. Invasive GBS infections incidence in infants (0.18/1000 live births) showed a decreasing trend (0.3 to 0.1/1000 live births). Type III was overrepresented in infants with invasive infections (n = 35, 58.3%), whereas type V predominated among colonised adults (n = 224, 25.5%) and those with noninvasive (n = 37, 32.5%) and invasive infections (n = 8, 40%). The hypervirulent clone III/ST17 was highly associated with invasive infections (n = 28, 35%), particularly late-onset disease (n = 9, 47.4%), showing an increase from 12.3 to 14.8%. The GBS resistance to erythromycin and clindamycin was 26.7% and 22.1%, respectively, with an upward trend. The emergence of the hypervirulent clone III/ST17 and the escalation in GBS resistance highlight an urgent need for continuous monitoring of GBS infections.

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