Filamentous Capsulated Streptococci from the Human Respiratory Tract I. Antigenic Attributes of Provisional Capsular Type 83 and Its Relationship to Streptococci of So-Called Group M

Abstract

Two immunologically reactive polysaccharides have been isolated from the cell walls and from culture filtrates of a filamentous alpha-hemolytic streptococcus provisionally designated capsular type 83. Both polysaccharides were purified by diethylaminoethyl-cellulose chromatography. Analysis indicates that the capsular polysaccharide consists of galactose and phosphorus, whereas the cell wall polysaccharide contains galactosamine, glucosamine, glucose, and phosphorus. On the basis of immunochemical experiments, it is suggested that the capsular polysaccharide is composed of galactose-phosphate units with terminal galactose residues at the nonreducing end. It has also been found that the capsular antigen of streptococcus type 83 is shared by a number of streptococcal strains classified in Lancefield's group M. The cell wall polysaccharide of streptococcus type 83 cross-reacts with antibody to the C8, or cell wall-like capsular, polysaccharide of Diplococcus pneumoniae, and this cross-reactivity may be a reflection that the streptococcal antigen possesses certain structural features which are similar to those of pneumococcal C and C8 polysaccharides.

Glycerolphosphate-Containing Cell Wall Polysaccharides fromStreptococcus sanguis

“…DISCUSSION The cell wall polysaccharides extracted from streptococcal walls with 0.5 N HCI (pH 2) at 100 C (19), formamide at 170 C (11) and Streptomyces albus enzyme (21) have been found to be composed of rhamnose, glucose, galactose, N-acetylglucosamine, and N-acetylgalactosamine in various combinations (29). We have fractionated the cell wall polysaccharide(s) of S. sanguis into at least four fractions to the purity of 95% or more as judged by polyacrylamide gel (15,16,17) reported that the cell wall polysaccharides of three filamentous streptococci isolated from a human respiratory tract contained phosphate in addition to glucosamine, galactosamine, and glucose, but the presence of glycerol was not reported. Recently (Table 1).…”

Filamentous Capsulated Streptococci from the Human Respiratory Tract III. Immunochemical Studies of the Cross-Reactivity Between the Cell Wall Antigens of a Filamentous Streptococcus and of Pneumococcus

“…Preliminary evidence has suggested that the cross-reacting cell wall antigens of these filamentous streptococci have similar immunological features and might represent, therefore, a common group-specific antigen. Previous studies have shown that the cell wall antigen of the prototypic strain of filamentous streptococcal capsular type 83 contains galactosamine, glucosamine, glucose, and phosphorus (16). Although an immunological relationship was demonstrated between this antigen and pneumococcal C polysaccharide, the immunochemical basis for the cross-reactivity was not defined.…”

“…Earlier studies have drawn attention to the immunological cross-reactivity between the C. capsular polysaccharide of pneumococcus (5) and a variety of strains of capsulated filamentous alphaand nonhemolytic streptococci of the human respiratory tract (2,16). Such an immunological relationship is consistent with the observation that the cell walls of pneumococcus and of a filamentous streptococcus studied previously have in common certain chemical constituents, namely galactosamine, glucosamine, glucose, phosphate, and several amino acids (16). In the following experiments, the immunochemical basis for the cross-reactivity between the cell walls of pneumococcus and of a filamentous alpha-hemolytic streptococcus has been investigated in greater detail.…”

“…Previous studies have indicated that immunological cross-reactivity exists between the cellular antigens of some strains of alphaand nonhemolytic filamentous streptococci of the human respiratory tract and the C, or cell wall, polysaccharide of pneumococcus (2). In an extension of the initial observations, a cell wall carbohydrate, reacting with an antiserum to the C8, or cell wall-like capsular polysaccharide of pneumococcus (5) and consisting of glucose, galactose, glucosamine, galactosamine, and phosphorus, was isolated from the prototypic strain of the alpha-hemolytic filamentous streptococcus provisionally designated type 83 (16). Studies of the cell wall antigen of this organism demonstrated that an immunological similarity existed between it and the cell wall antigen of pneumococcus, but the immunochemical basis for this cross reactivity was not defined.…”

Filamentous Capsulated Streptococci from the Human Respiratory Tract II. Antigenic Structure of Provisional Capsular Types 89 and 83/89

“…It has been found previously that many strains of alphaand nonhemolytic streptococci isolated from human respiratory secretions produce type-specific capsular substances (2,11). Extensive immunological studies of a collection of filamentous morphological variants giving rise to rugose colonies on the surface of agar plates have revealed the existence of at least 30 capsular serotypes.…”