Electron Microscopic Studies on Streptococci

1970 ◽  
Vol 28 ◽  
pp. 194-195
Author(s):  
JOHN SWANSON M.D.
Keyword(s):  
Cell Walls ◽  
Teichoic Acid ◽  
Chemical Components ◽  
Group A Streptococci ◽  
Electron Microscopic ◽  
Histochemical Methods ◽  
Specific Polysaccharide ◽  
Microscopic Studies ◽  
Group A ◽  
Comparative Examination

Group A streptococci contain a variety of chemical components in their cell walls. The major components are mucopeptide, group-specific polysaccharide, protein constituents (M,T, and R), and teichoic acid. Investigations have been carried out to determine the location of each of these classes of chemical components. The techniques used include simple, comparative examination of selected strains that lack or possess a particular component, electron histochemical methods, immunoferritin methods, and extraction or removal of a particular component.

scholarly journals ELECTRON MICROSCOPIC STUDIES ON STREPTOCOCCI

1973 ◽  
Vol 138 (1) ◽  
pp. 245-258 ◽  
Author(s):  
John Swanson ◽  
Emil C. Gotschlich
Keyword(s):  
Cell Wall ◽  
Horseradish Peroxidase ◽  
Electron Microscopic ◽  
Streptococcal Cell Wall ◽  
Outermost Surface ◽  
Laminar Distribution ◽  
Specific Polysaccharide ◽  
Microscopic Studies ◽  
Group A ◽  
Protein Cell

The location of Group A carbohydrate in the streptococcal cell wall has been studied by several ultrastructural techniques. The findings, based largely on use of ferritin- and horseradish peroxidase-conjugated antibodies, are interpreted as demonstrating a discrete laminar distribution of the group-specific polysaccharide. This carbohydrate layer is located on the outermost surface of the cell wall in organisms lacking protein cell wall antigens.

scholarly journals STUDIES OF L FORMS AND PROTOPLASTS OF GROUP A STREPTOCOCCI

1959 ◽  
Vol 110 (6) ◽  
pp. 853-874 ◽  
Author(s):  
Earl H. Freimer ◽  
Richard M. Krause ◽  
Maclyn McCarty
Keyword(s):  
Cell Wall ◽  
Cell Walls ◽  
M Protein ◽  
Group A Streptococci ◽  
Group A ◽  
Isolated Cell ◽  
Streptococcal Strain

L forms of Group A streptococci have been isolated by the use of penicillin gradient agar plates. Osmotically fragile protoplasts of Group A streptococci have been obtained by the use of Group C phage-associated lysin which lyses Group A streptococci and their isolated cell walls. Membranes surrounding these enzymatically derived protoplasts have been isolated, and chemical and immunological studies indicate that they are free of cell wall carbohydrate and M protein. The streptococcal protoplasts reproduce as colonies which are morphologically indistinguishable from streptococcal L forms. Evidence is presented to show that these two streptococcal derivatives are serologically and physiologically related to each other as well as to the parent streptococcal strain from which they were isolated.

scholarly journals Modulation of the susceptibility of inbred and outbred rats to arthritis induced by cell walls of group A streptococci.

1979 ◽  
Vol 25 (2) ◽  
pp. 484-490 ◽  
Author(s):  
S K Anderle ◽  
J J Greenblatt ◽  
W J Cromartie ◽  
R Clark ◽  
J H Schwab
Keyword(s):  
Cell Walls ◽  
Group A Streptococci ◽  
Group A

scholarly journals Differential distributions in tissues and efficacies of aztreonam and ceftazidime and in vivo bacterial morphological changes following treatment.

1997 ◽  
Vol 41 (2) ◽  
pp. 401-409 ◽  
Author(s):  
A Turcotte ◽  
M Simard ◽  
N J Morin ◽  
D Beauchamp ◽  
M G Bergeron
Keyword(s):  
Cell Walls ◽  
Morphological Changes ◽  
Enterobacter Cloacae ◽  
Control Group ◽  
Electron Microscopic ◽  
Penetration Ratio ◽  
Microscopic Studies ◽  
Bow Tie ◽  
Fibrin Clots

The differential tissue distributions of aztreonam and ceftazidime within fibrin clots infected with Pseudomonas aeruginosa, Enterobacter cloacae, and Serratia marcescens, their efficacies, and the in vivo bacterial morphological changes induced by these drugs were evaluated. Rabbits were given intravenously a single dose of 100 mg of either agents/kg of body weight. In the cores of the clots, the peak levels of both drugs were much lower than those observed in the peripheries and in serum. Aztreonam's half-lives within the peripheries and in the cores of the fibrin clots were up to six times higher than observed in serum, while ceftazidime's half-lives in clots were twice that observed in serum. This resulted in a much greater penetration ratio for aztreonam than for ceftazidime. Both drugs controlled the growth of P. aeruginosa in vivo, but E. cloacae and S. marcescens responded better to ceftazidime. Morphological changes were more abundant in the peripheries than in the cores of the clots. In the control group, P. aeruginosa's morphology in the cores was different than that in the peripheries of the clots. Against P. aeruginosa, aztreonam did induce morphological changes in the cores while ceftazidime did not. Electron microscopic studies revealed that morphological changes associated with aztreonam seemed different than those of ceftazidime. Along with elongation of bacteria, more bow tie and herniated bacteria were observed with aztreonam. Though both agents selectively affect PBP 3, as manifested by elongated bacteria, they induce in the peripheries of the clots thickening, breaks, and detachment in bacterial cell walls, alterations which are generally associated with antibiotics affecting PBP 1a and 1b.

scholarly journals ENHANCED RESISTANCE TO STREPTOCOCCAL INFECTION INDUCED IN MICE BY CELL WALL MUCOPEPTIDE

1965 ◽  
Vol 122 (5) ◽  
pp. 877-890 ◽  
Author(s):  
Jiri Rotta ◽  
Thomas J. Prendergast ◽  
Walter W. Karakawa ◽  
Charles K. Harmon ◽  
Richard M. Krause
Keyword(s):  
Cell Wall ◽  
Cell Walls ◽  
Streptococcal Infection ◽  
Group A Streptococci ◽  
Streptococcal Cell Wall ◽  
Enhanced Resistance ◽  
Group A ◽  
Late Recovery ◽  
Fever Response ◽  
Virulent Group

The streptococcal cell wall mucopeptide when injected into mice either intraperitoneally or intravenously enhances the resitance to subsequent challenge with virulent Group A streptococci. Rabbits which are injected intravenously with solubilized mucopeptide develop a fever response which has a resemblance to that achieved with endotoxin. Mice which survive 6 to 7 weeks after challenge with virulent Group A streptococci yield at autopsy search Group A streptococci serologically identical to the challenge organisms. A preparative dose of cell walls injected into mice prior to challenge diminished this late recovery of streptococci. Group A-variant streptococci were recovered from mice which survived challenge and carried the organisms for several weeks. Filterable bacterial forms, which grew on L form media, were recovered from infected mice. The serologic type of the L forms was identical to that of the challenge organisms.

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