scholarly journals Spread of Virulent Group AStreptococcusTypeemm59from Montana to Wyoming, USA

2014 ◽  
Vol 20 (4) ◽  
pp. 658-660 ◽  
Author(s):  
Christopher C. Brown ◽  
Randall J. Olsen ◽  
Nahuel Fittipaldi ◽  
Monica L. Morman ◽  
Peter L. Fort ◽  
...  
Keyword(s):  
Virulent Group

Rapid detection of the “highly virulent” group B streptococcus ST-17 clone

2006 ◽  
Vol 8 (7) ◽  
pp. 1714-1722 ◽  
Author(s):  
Marie-Cécile Lamy ◽  
Shaynoor Dramsi ◽  
Annick Billoët ◽  
Hélène Réglier-Poupet ◽  
Asmaa Tazi ◽  
...  
Keyword(s):  
Rapid Detection ◽  
Group B Streptococcus ◽  
Group B ◽  
Highly Virulent ◽  
Virulent Group

scholarly journals Stable genetic integration of a red fluorescent protein in a virulent Group A Streptococcus strain

2019 ◽  
Vol 1 (9) ◽  
Author(s):  
Zhong Liang ◽  
Katelyn Carothers ◽  
Adam Holmes ◽  
Deborah Donahue ◽  
Shaun W. Lee ◽  
...  
Keyword(s):  
Fluorescent Protein ◽  
Group A Streptococcus ◽  
Red Fluorescent Protein ◽  
Group A ◽  
Genetic Integration ◽  
Virulent Group

scholarly journals FATE OF NON-VIRULENT GROUP A STREPTOCOCCI PHAGOCYTIZED BY HUMAN AND MOUSE NEUTROPHILS

1957 ◽  
Vol 106 (6) ◽  
pp. 777-786 ◽  
Author(s):  
Armine T. Wilson ◽  
Grove G. Wiley ◽  
Pauline Bruno
Keyword(s):  
Electric Current ◽  
Peripheral Blood ◽  
Group A Streptococci ◽  
Blood Neutrophils ◽  
Group A ◽  
Time Required ◽  
Human And Mouse ◽  
Virulent Group

The fate of non-virulent group A streptococci phagocytized in vitro has been investigated by destroying the phagocyte with electric current and observing whether the liberated cocci multiply. Human and mouse peripheral blood neutrophils quickly injure ingested cocci, the time required to produce 50 per cent non-survival of chains being 8 and 6¾ minutes, respectively.

scholarly journals INTERGROUP PHAGE REACTIONS AND TRANSDUCTION BETWEEN GROUP C AND GROUP A STREPTOCOCCI

1973 ◽  
Vol 137 (6) ◽  
pp. 1338-1353 ◽  
Author(s):  
Lewis W. Wannamaker ◽  
Susan Almquist ◽  
Stephen Skjold
Keyword(s):  
High Titer ◽  
Significant Proportion ◽  
Indicator Strain ◽  
Streptomycin Resistance ◽  
Group A Streptococci ◽  
Single Group ◽  
Homologous Group ◽  
Forming Efficiency ◽  
Group A ◽  
Virulent Group

In a study of intergroup reactions, four virulent Group A streptococcal phages were found to form plaques in high titer on lawns prepared from a number of Group C streptococcal strains. Whether the phages were propagated on the homologous (Group A) strain or a heterologous (Group C) strain did not appear to influence consistently the plaque-forming efficiency on lawns prepared from a homologous (Group A) or a heterologous (Group C) strain or to alter significantly the percent of Group C strains which showed plaque formation. Considerable variability was found in the ability of temperate phages to lyse strains of a heterologous group. A single Group C indicator strain was lysed by a high percentage of freshly induced temperate Group A phages. A single temperate Group C phage lysed a significant proportion of Group A strains when freshly induced or when propagated on a Group A strain. Intragroup transduction of streptomycin resistance was demonstrated between Group C strains. Intergroup transduction of streptomycin resistance and also bacitracin resistance was achieved between Group C and Group A streptococci. These observations provide evidence that Group A streptococci can serve as recipients in intergroup transmission of genetic information. Ultraviolet irradiation of the transducing lysate and lowering the propagation temperature of the transducing lysate increased the frequency of transduction in both the intragroup and intergroup transduction systems.

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.

scholarly journals THE EFFECT OF A POLYSACCHARIDE-SPLITTING ENZYME ON STREPTOCOCCAL INFECTION

1941 ◽  
Vol 73 (4) ◽  
pp. 493-506 ◽  
Author(s):  
George K. Hirst
Keyword(s):  
Molecular Weight ◽  
Streptococcal Infection ◽  
Protective Action ◽  
Intraperitoneal Administration ◽  
Group A Streptococci ◽  
Group A ◽  
Intraperitoneal Infection ◽  
Virulent Group

1. Confirming the observations of other experimenters, it has been found that group A hemolytic streptococci produce a capsule containing a polysaccharide which is similar to, if not identical with, certain high molecular weight sugars found in the mammalian body. 2. Leech extract possesses a powerful enzyme capable of splitting one of the linkages in this polysaccharide and of decapsulating group A and group C hemolytic streptococci in vitro and in vivo. 3. Mice and guinea pigs can be protected from intraperitoneal infection with a virulent group C streptococcus by the intraperitoneal administration of leech extract. In contrast there is little protective action of leech extract in mice infected with group A hemolytic streptococci. 4. The protective effect of leech extract against streptococcal group C infection is probably due to the removal of the capsule in vivo. 5. The capsule of mouse virulent group C streptococci plays a major rôle in the virulence of that microorganism, while the capsule of certain mouse virulent group A streptococci plays little, if any, rôle in virulence, at least when the infection is intraperitoneal in the mouse.

scholarly journals FACTORS AFFECTING THE CHAIN LENGTH OF GROUP A STREPTOCOCCI

1960 ◽  
Vol 112 (4) ◽  
pp. 687-698 ◽  
Author(s):  
Richard D. Ekstedt ◽  
Gene H. Stollerman
Keyword(s):  
Surface Antigens ◽  
M Protein ◽  
Specific Inhibition ◽  
Group A Streptococci ◽  
Factors Affecting ◽  
Low Concentrations ◽  
Group A ◽  
Virulent Group ◽  
Long Chain ◽  
Long Chains

Minute amounts of M protein were detected in culture supernates of virulent Group A streptococci by type-specific inhibition of the long chain and the bactericidal tests for anti-M antibody. The amount of M protein that was detected by the inhibition of these biological systems was less than could be demonstrated by precipitation tests. All strains of streptococci rich in M protein which were studied formed long chains when grown in sufficient concentrations of anti-M antibody. Very low concentrations of anti-M antibody escaped detection by the long chain test when strains of excessive M protein content were employed. Under such conditions the bactericidal test detected anti-M antibody more sensitively than the long chain test owing to the smaller inoculum employed in the former method. The scission of streptococcal chains may be inhibited by union of antibodies with surface antigens other than M protein. Long chains were formed when M-negative, R-positive strains were grown in sera containing anti-R antibody.

scholarly journals Influences of Linezolid, Penicillin, and Clindamycin, Alone and in Combination, on Streptococcal Pyrogenic Exotoxin A Release

2003 ◽  
Vol 47 (5) ◽  
pp. 1752-1755 ◽  
Author(s):  
Elizabeth A. Coyle ◽  
Raymond Cha ◽  
Michael J. Rybak
Keyword(s):  
In Vitro Model ◽  
Group A Streptococci ◽  
Bacterial Burden ◽  
Exotoxin A ◽  
Group A ◽  
Vitro Model ◽  
Virulent Group

ABSTRACT An in vitro model was used to compare the effects of linezolid, clindamycin, and penicillin, alone and in combination, on streptococcal pyrogenic exotoxin A (SPE A) release against virulent group A streptococci (GAS). All regimens exhibited lower (P < 0.05) SPE A release at 1 h than those with penicillin alone. Linezolid and clindamycin, alone or in combination with penicillin, may optimize the treatment of GAS infections by reducing bacterial burden and exotoxin release.

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