The specific capsular polysaccharide of pneumococcus type I and the immunity which it induces in mice

1937 ◽  
Vol 45 (1) ◽  
pp. 131-147 ◽  
Author(s):  
Allan W. Downie
Keyword(s):  
Capsular Polysaccharide ◽  
Type I ◽  
Pneumococcus Type

scholarly journals SIMULTANEOUS PRODUCTION OF TWO CAPSULAR POLYSACCHARIDES BY PNEUMOCOCCUS

1959 ◽  
Vol 110 (4) ◽  
pp. 585-602 ◽  
Author(s):  
Robert Austrian ◽  
Harriet P. Bernheimer ◽  
Evelyn E. B. Smith ◽  
George T. Mills
Keyword(s):  
Capsular Polysaccharide ◽  
Phenotypic Expression ◽  
The Other ◽  
Type I ◽  
Capsular Type ◽  
Biochemical Reactions ◽  
Biochemical Basis ◽  
Transformed Cell ◽  
Partial Suppression ◽  
Pneumococcus Type

Study of the capsular genome of pneumococcus has shown that it controls a multiplicity of biochemical reactions essential to the synthesis of capsular polysaccharide. Mutation affecting any one of several biochemical reactions concerned with capsular synthesis may result in loss of capsulation without alteration of other biochemical functions similarly concerned. Mutations affecting the synthesis of uronic acids are an important cause of loss of capsulation and of virulence by strains of pneumococcus Type I and Type III. The capsular genome appears to have a specific location in the total genome of the cell, this locus being occupied by the capsular genome of whatever capsular type is expressed by the cell. Transformation of capsulated or of non-capsulated pneumococci to heterologous capsular type results probably from a genetic exchange followed by the development of a new biosynthetic pathway in the transformed cell. The new capsular genome is transferred to the transformed cell as a single particle of DNA. Binary capsulation results from the simultaneous presence within the pneumococcal cell of two capsular genomes, one mutated, the other normal. Interaction between the biochemical pathways controlled by the two capsular genomes leads to augmentation of the phenotypic expression of the product controlled by one and to partial suppression of the product determined by the other. Knowledge of the biochemical basis of binary capsulation can be used to indicate the presence of uronic acid in the capsular polysaccharide of a pneurnococcal type the composition of the capsule of which is unknown.

scholarly journals The Capsular Polysaccharide of Type I Pneumococcus

1967 ◽  
Vol 242 (21) ◽  
pp. 5106-5111
Author(s):  
R.C.E. Guy ◽  
M.J. How ◽  
M. Stacey ◽  
Michael Heidelberger
Keyword(s):  
Capsular Polysaccharide ◽  
Type I

scholarly journals FACTORS INVOLVED IN THE PRODUCTION OF IMMUNITY WITH PNEUMOCOCCUS VACCINE

1928 ◽  
Vol 48 (1) ◽  
pp. 83-104 ◽  
Author(s):  
Alvan L. Barach ◽  
Keyword(s):  
Intact Cell ◽  
Broth Culture ◽  
Time Interval ◽  
Type I ◽  
Type Ii ◽  
Lobar Pneumonia ◽  
The Common ◽  
Immunity Mechanism ◽  
Lethal Doses ◽  
Pneumococcus Type

1. The antigenic function of a pneumococcus vaccine made from the intact cell was compared with that derived fron a watery extract of the cell free from formed elements. In each instance, the immunity produced was dependent upon type-specific protective substance and not upon the elaboration of the common protein antibody. 2. The vaccine made from the intact cell resulted in both active and passive immunity which began on the 3rd day, increased markedly to the 5th, and remained approximately stationery to the 7th day. In the case of the Berkefeld filtrate of the shaken bacteria and the filtrate of the broth culture, the immunity began on the 4th day, increased to the 5th, and remained approximately stationery to the 7th day. The immunity produced by Pneumococcus Type I vaccine is greater than that produced by Type II. On the 3rd day, mice vaccinated with Type I vaccine resisted 100,000 minimal lethal doses, whereas mice immunized with Type II resisted 10,000 minimal lethal doses. On the 5th day, a larger percentage of mice survived these doses than on the 3rd day. 3. Certain factors related to the preparation and dosage of the vaccine are discussed. 4. As far as the time interval and the degree of immunity produced are concerned, these results suggest the possibility of employing pneumococcus vaccine in suitable doses in the treatment of lobar pneumonia. That an earlier activity of the immunity mechanism could actually be initiated in a patient with lobar pneumonia has still to be demonstrated.

scholarly journals Polysaccharides and virulence of Burkholderia pseudomallei

2007 ◽  
Vol 56 (8) ◽  
pp. 1005-1010 ◽  
Author(s):  
M. Sarkar-Tyson ◽  
J. E. Thwaite ◽  
S. V. Harding ◽  
S. J. Smither ◽  
P. C. F. Oyston ◽  
...  
Keyword(s):  
Burkholderia Pseudomallei ◽  
Capsular Polysaccharide ◽  
Gene Clusters ◽  
Type I ◽  
Wild Type ◽  
Time To Death ◽  
Type Iii ◽  
Type Iv ◽  
Mutant Strains ◽  
Delayed Time

Burkholderia pseudomallei is the causative agent of melioidosis, an infectious disease of humans and animals. Gene clusters which encode capsular polysaccharide (type I O-PS) and LPS (type II O-PS), both of which play roles in virulence, have previously been identified. Here, the identification of two further putative clusters, type III O-PS and type IV O-PS, is reported. Mice challenged with type III O-PS or type IV O-PS mutants showed increased mean times to death (7.8 and 11.6 days) compared to those challenged with wild-type B. pseudomallei (3 days). To investigate the possible roles of polysaccharides in protection, mice were immunized with killed cells of wild-type B. pseudomallei or killed cells of B. pseudomallei with mutations in the O antigen, capsular polysaccharide, type III O-PS or type IV O-PS gene clusters. Immunization with all polysaccharide mutant strains resulted in delayed time to death compared to the naïve controls, following challenge with wild-type B. pseudomallei strain K96243. However, immunization with killed polysaccharide mutant strains conferred different degrees of protection, demonstrating the immunological importance of the polysaccharide clusters on the surface of B. pseudomallei.

scholarly journals STUDIES ON INFLAMMATION

1933 ◽  
Vol 57 (6) ◽  
pp. 977-991 ◽  
Author(s):  
Valy Menkin
Keyword(s):  
Staphylococcus Aureus ◽  
Inflammatory Reaction ◽  
Trypan Blue ◽  
Type I ◽  
Mechanical Obstruction ◽  
Cutaneous Inflammation ◽  
The Difference ◽  
Set Up ◽  
Pneumococcus Type

Trypan blue injected into an area of cutaneous inflammation induced by Staphylococcus aureus failed to drain readily to the tributary lymphatics when the dye was injected as early as 1 hour after the inoculation of the microorganisms. Trypan blue introduced into an area of cutaneous inflammation induced by Pneumococcus Type I was retained in situ when the dye was injected about 6 or more hours after the inoculation of the bacteria. When an area of cutaneous inflammation was induced by the inoculation of a culture of Streptococcus hemolyticus, trypan blue injected into it drained readily to the tributary lymphatics for the first 30 hours following the onset of the inflammatory reaction. When the inflammation had lasted for 45 hours or longer, the dye was fixed in situ and failed in most instances to reach readily the tributary lymphatics. The rapidity of fixation of the dye in the instances given would appear to depend on mechanical obstruction in the form of both a fibrinous network and thrombosed lymphatics or thrombosed lymphatics alone at the site of inflammation. Inasmuch as staphylococci, pneumococci, and streptococci spread from the site of cutaneous inoculation primarily through lymphatic channels, the difference in the rapidity with which mechanical obstruction is set up in the areas inflamed by them will help to explain the differing invasive abilities of these pyogenic organisms.

A multimeric matrix-associated lectin (RapD) affects proper exopolysaccharide processing in Rhizobium leguminosarum

2020 ◽  
Author(s):  
Julian Tarsitano ◽  
Daniela Marta Russo ◽  
Leonardo Alonso ◽  
Angeles Zorreguieta
Keyword(s):  
Calcium Binding ◽  
Rhizobium Leguminosarum ◽  
Capsular Polysaccharide ◽  
The Other ◽  
Size Exclusion ◽  
Type I ◽  
Dependent Manner ◽  
Extracellular Medium ◽  
Bacterial Surface ◽  
Biofilm Matrix

<p><em>Rhizobium leguminosarum</em> synthesizes an acidic polysaccharide formed by the polymerization of octasaccharide repeating units containing glucose (Glc), glucuronic acid (GlcA) and galactose (Gal) in a 5:2:1 ratio with particular substitutions; most of it is secreted to the extracellular medium (EPS) and part of it is retained on the bacterial surface as a capsular polysaccharide (CPS). Rap proteins, substrates of the PrsDE type I secretion system (TISS) share at least one Ra/CDHL (cadherin-like) domain and are involved in biofilm and matrix development either by cleaving the polysaccharide (Ply glycanases) or by altering the bacterial adhesive properties. Previous studies have shown that RapA2 is a monomeric calcium-binding lectin capable of binding specifically the <em>R. leguminosarum</em> CPS through a Ra/CDHL domain. It was shown that the absence or excess of RapA2 in the extracellular medium alters the biofilm matrix’s properties.</p> <p>In this work we identified a new Rap protein (RapD), which comprises an N-terminal Ra/CDHL domain and a C-terminal domain of unknown function. By Western blot analysis using specific polyclonal antibodies we showed that in planktonic cultures RapD is co-secreted with the other Rap proteins in a PrsDE-dependent manner. Furthermore, under conditions that favor EPS production, a prominent RapD secretion was observed. In addition, colony blot assays indicated that RapD is associated with the biofilm matrix.  Interestingly, size exclusion chromatography of the EPS produced by the Δr<em>apA2</em> Δ<em>rapD</em> double mutant showed differences in the EPS profiles compared with those of the single mutants and the wild type strain, thus suggesting a functional interaction between the RapA2 and RapD proteins.</p> <p> Biophysical studies showed that calcium triggers proper folding and multimerization of recombinant RapD. Besides, further RapD conformation changes were observed in the presence of EPS.</p> <p>ELISA and BIA (binding inhibition assay) assays showed that in the presence of calcium, RapD specifically binds the EPS and that galactose residues would be involved in this interaction.</p> <p>In conclusion, RapD is a multimeric calcium-dependent EPS lectin that is co-secreted with the other Rap proteins via TISS PrsDE. Unlike RapA2, RapD is not retained on the bacterial surface but would rather interact with the released EPS. Finally, our results suggest that the interaction of RapA2 and RapD with the CPS or the EPS somehow affects the polysaccharide processing and therefore the biofilm matrix.</p>

A FAMILY OUTBREAK OF PNEUMOCOCCUS TYPE I INFECTIONS.*

1941 ◽  
Vol 201 (1) ◽  
pp. 100-105
Author(s):  
NORMAN PLUMMER ◽  
HERBERT K. ENSWORTH
Keyword(s):  
Type I ◽  
Family Outbreak ◽  
Pneumococcus Type
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