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R M KRAUSE

Publications and source records attributed to R M KRAUSE.

At least 19 recordsLinked to original sources

THE CELL WALLS OF GROUP D STREPTOCOCCI. I. THE IMMUNOCHEMISTRY OF THE TYPE 1 CARBOHYDRATE.

Group D Types 1 and 26 cell walls and the corresponding type-specific carbohydrates, extracted from the walls by various means, contain rhamnose, glucose, galactose, N-acetylglucosamine, and N-acetylgalactosamine. Mucopeptide elements are also present in the walls and in enzymatically-extracted carbohydrates. Types 1 and 26 carbohydrates extracted by formamide contain no mucopeptide, but the serologic reactivity of Type 1 antigen is destroyed by this procedure. The Type 1 antigen was successfully extracted, however, by a new technique involving autolysis of cell walls at pH 6.2. The type carbohydrate prepared by this procedure has chemical and serological similarities to the antigens prepared by the S. albus enzyme and the lysozyme methods. Quantitative precipitin inhibition studies with Type 1 antigen and antibody indicate that D-glucose and N-acetylglucosamine may be components of the antigenic determinant. The terminal residue is probably bound by an beta-glycosidic bond to the subterminal sugar. Similar studies with the Type 26 carbohydrate have not revealed any of the chemical features of the antigenic determinant.

Antibodies↗

ISOLATION OF L FORMS FROM GROUP A STREPTOCOCCI EXPOSED TO BACITRACIN.

Rotta, Jiri (Washington University School of Medicine, St. Louis, Mo.), Walter W. Karakawa, and Richard M. Krause. Isolation of L forms from group A streptococci exposed to bacitracin. J. Bacteriol. 89:1581-1585. 1965.-L forms were obtained from group A streptococci by exposure to bacitracin on gradient plates, although novobiocin was ineffective in this respect. Subcultures of these L forms had morphological and bacteriological properties similar to those obtained with penicillin. M protein was detected in L-form colony smears by immunofluorescent staining with type-specific conjugate. The L forms were not stained with group-specific conjugate. Parallel precipitin tests performed with extracts from a heavy growth of L forms on agar confirmed these findings. Thus, the L forms obtained with bacitracin continue to produce M protein but are devoid of the group-specific carbohydrate which is a major component of cell-wall structure.

Bacitracin↗

ANTIGENIC RELATIONSHIPS BETWEEN GROUPS B AND G STREPTOCOCCI.

Trypsinized cell walls of Group B hemolytic streptococci are composed of a group-specific carbohydrate and mucopeptide. The carbohydrate extracted with hot formamide is composed of rhamnose, N-acetylglucosamine, and galactose. Quantitative precipitin inhibition studies have shown that L rhamose is the significant component of the antigenic determinant. The cross-reactivity between B and G carbohydrates is dependent upon the fact that Lrhamose is a determinant sugar in both antigens.

Antigens↗

IMMUNOCHEMICAL STUDIES ON THE SPECIFIC CARBOHYDRATE OF GROUP G STREPTOCOCCI.

Group G hemolytic streptococcal cell walls which have been treated with trypsin are composed of a group-specific polysaccharide moiety and a mucopeptide matrix. The mucopeptide contains N-acetylglucosamine, N-acetylmuramic acid, alanine, glutamic acid, lysine, and glycine, a composition similar to that of other groups of streptococci. The Group G carbohydrate is composed of rhamnose, N-acetylgalactosamine, and galactose. Serological studies suggest that the monosaccharide of L-rhamnose is a major component of the determinant of antigenic specificity.

Alanine↗

GROUP-SPECIFIC CARBOHYDRATE OF GROUP C-VARIANT HEMOLYTIC STREPTOCOCCI.

The trypsinized cell walls of Group C hemolytic streptococci are composed of the specific carbohydrate antigen and a mucopeptide matrix. Certain phage resistant strains of Group C streptococci, isolated from organisms which survive exposure to Group C bacteriophage also possess carbohydrate and mucopeptide fractions, but the carbohydrate gives a precipitin reaction with Group A-variant antiserum and not with Group C antiserum. These strains have been termed Group C-variant. The C-variant carbohydrate contains 86 per cent rhamnose and only 2 per cent galactosamine, and is thus chemically and immunologically similar to Group A-variant carbohydrate. The evidence suggests that the antigenic determinants of Groups A-variant and C-variant carbohydrates are rhamnose-rhamnose linkages. These results strongly support the hypothesis that the carbohydrates of Groups A and C streptococci are composed of a similar rhamnose moiety but that the determinant amino sugar terminal to the rhamnose-rhamnose linkages in the case of Group A is N-acetylglucosamine whereas that of Group C is N-acetylgalactosamine.

Alanine↗

Variation in the group-specific carbohydrate of group C hemolytic Streptococci.

Certain strains of Group C hemolytic streptococci, termed Group C-intermediate, contain a group-specific carbohydrate antigen which gives a precipitin cross-reaction with A-variant antiserum. The carbohydrate antigens of these strains have a rhamnose:hexosamine ratio ranging from 2.4 to 2.6 whereas the ratio of typical Group C strains varies between 1.1 and 1.7. N-acetylgalactosamine, the major hexosamine in all of these strains is the principle determinant of Group C specificity. The high concentration of rhamnose in the C-intermediate carbohydrate suggests that a portion of the rhamnose oligosaccharide side chains are devoid of terminal N-acetylgalactosamine and thus react with Group A-variant antiserum. This view is supported by the fact that the induced variant enzyme, which destroys A-variant carbohydrate reactivity with the liberation of rhamnose oligosaccharides, has a similar action upon the Group C-intermediate carbohydrate. C-intermediate carbohydrate, after treatment with variant enzyme which removed approximately 25 per cent of the rhamnose, does not react with A-variant antisera.

Carbohydrate Metabolism↗

Studies on the chemical structure of the streptococcal cell wall. II. The composition of group C cell walls and chemical basis for serologic specificity of the carbohydrate moiety.

The trypsinized cell walls of Group C streptococci contain two components, the group-specific carbohydrate and a mucopeptide polymer. Hot formamide extraction of Group C cell walls results in a soluble group-specific carbohydrate fraction and an insoluble mucopeptide residue. This mucopeptide, similar in composition to that of Groups A and A-variant streptococci, contains N-acetylglucosamine, N-acetylmuramic acid, alanine, glutamic acid, lysine, and glycine. It is dissolved by the muralytic enzymes, including lysozyme, which does not attack the whole cell wall. Lysis of the cell wall by phage-associated lysin results in the release of soluble fragments composed of the elements of mucopeptide. Group C carbohydrate extracted with formamide is composed primarily of N-acetylgalactosamine and rhamnose. Serological studies suggest that the specificity of Group C carbohydrate is determined by the N-acetylgalactosamine.

Carbohydrates↗

Studies on the chemical structure of the streptococcal cell wall. I. The identification of a mucopeptide in the cell walls of groups A and A-variant streptococci.

Lysis of trypsinized Group A streptococcal cell walls with phage-associated lysin releases into solution dialyzable and non-dialyzable mucopeptide fractions composed of N-acetylglucosamine, N-acetylmuramic acid and alanine, glutamic acid, lysine, and glycine in addition to the characteristic group-specific carbohydrate. The latter substance contains appreciable amounts of N-acetylmuramic acid and the amino acids as well as N-acetylglucosamine and rhamnose. Hot formamide extraction of the cell walls results in a soluble fraction of group-specific carbohydrate and an insoluble residue. The Group A carbohydrate in this instance is composed of rhamnose and N-acetylglucosamine. The composition of the insoluble residue is similar to that of the mucopeptide fractions released from the cell wall by phage-associated lysin. This residue was shown by electron microscopy to be composed of discrete discs which appear similar in structure to the intact cell wall. The specific carbohydrate obtained by hot formamide extraction of Group A-variant cell walls was composed almost exclusively of rhamnose. The residue fraction was similar to that of Group A. The residue of cell walls extracted with hot formamide is extensively solubilized not only by phage-associated lysin and S. albus enzyme, but also by lysozyme, which has no measurable effect on the intact streptococcal cell wall.

Amino Acids↗

Studies of L forms and protoplasts of group A streptococci. I. Isolation, growth, and bacteriologic characteristics.

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.

Bacteriophages↗