Isolation of the Specific Carbohydrate of Type A Friedliinder Bacillus

The parallelism between capsular synthesis and virulence among pathogenic bacteria is one which has been extensively investigated, but researches concerning the chemical nature of encapsulating substances have indeed been very few. Fiirst (1) has described the encapsulating substance of the Friedliinder bacillus. He believed it to be a mucoprotein-like substance. Harem (2) contended that the capsulate substance contained nucleoprotein. Preisz (3) has attempted unsuccessfully to immunize animals with the capsular substance from the anthrax bacillus. More recently Toenniessen (4) succeeded in isolating a nitrogen-free polysaccharide from the Friedlander bacillus, which he believed to be identical with the capsular material of this microorganism. Similar polysaccharides have been isolated from cultures of the bacilli of the aerogenes group (5), from Streptococcus hornensls (6), and even from certain yeasts (7). Strange as it may seem, none of these earlier investigators ascribed immunological significance to these bacterial carbohydrates. The so called soluble specific substance of the pneumococcus, first observed by Dochez and Avery (8), has been identified with the polysaccharide portion of the organism. An extensive investigation into the chemical and immunological nature of carbohydrates from the pneumococcus group has been carried out in this laboratory (9). Similar investigations have recently been extended to the group of Friedlitnder bacilli. From a strain of Friedlitnder's bacillus, Mueller, Smith, and Litarczek (10) have recorded the isolation of carbohydrate-containing material which at high dilutions reacted specifically with homologous antibacterial serum. I t has been shown by Julianelle (11)