Tuberculin, polysaccharides from

In each instance, polysaccharides Avere found to play a fundamental part. More recent workers have considered the polysaccharides from three sources (o) those associated with the somatic portion of the cell (h) those associated with the lipids and (c) those associated with the tuberculin from the culture medium. The literature and variety of the results of these investigations is now so vast that in a review such as this, one cannot hope to give a complete survey of the field. The aim has rather been to arrive at a representative view of the work so far reported. 

The method has proved valuable in studies of the carbohydrate metabolism of microorganisms (105,106), sucrose utilization by fungi (87) and bacteria (22,26), and microbial polysaccharides, e. g., the carbohydrates in yeast cell wall (194,238), polysaccharides of soils (86,104), and polysaccharides from tuberculin and pneumococcus type II (157). 

An Antigenic Polysaccharide, Polysaccharide II, Isolated from Tuberculin, Florence B. Seibert, M. Stacey, and P. W. Kent, Biochim. Biophys. Acta, 3 (1949) 632-640. 

These results were confirmed in the main by Dorset and Henley. A polysaccharide was obtained from Long s synthetic medium after growth of M. tuberculosis, human strain. This polysaccharide showed a positive biuret test for protein, and underwent hydrolysis only with difficulty. D-Arabinose and D-mannose were identified in the hydrolysate. No glycuronic acid could be detected. On hydrolysis, the D-arabi-nose seemed to be liberated before the other constituents. It was concluded from the biological tests that the active principle of tuberculin concerned in eliciting the skin reaction was a protein. This work was repeated with polysaccharides derived from the culture medium of the bovine and avian strains of organisms, and very similar results were obtained. D-Arabinose and D-mannose were also identified in those polysaccharides. 

A separation of the nucleic acid, polysaccharide and protein fractions of tuberculin was effected by the Tiselius electrophoretic technique, which was developed for large scale work in this field by Seibert and Watson. The polysaccharide was relatively immobile and thus was easily removed from the protein and nucleic acid. At pH 5.0 (or less), the nucleic acid and protein traveled in the electrophoretic tube as a single component. At higher pH values, the two tended to move independently. It was probable that some of the protein and nucleic acid was present as nucleoprotein. 

Anderson RJ, Peck RL, Creighton MM (1940) The chemistry of the lipids of tubercle bacilli. LXL The polysaccharide of the phosphatide obtained from cell residues in the preparation of tuberculin. J Biol Chem 136 211-227... 

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