AN INVESTIGATION OF THE BACILLUS PASTEURI GROUP II. SPECIAL PHYSIOLOGY OF THE ORGANISMS

In the first accounts of Urobacillus Pasteurii by Miquel (1889, 1898) the organism was described as having been cultivated in bouillon and peptone media containing various concentrations of urea. Beijerinck (1901) found that the bacillus would not grow on the ordinary laboratory media, but developed in bouillon containing 10 per cent urea, or an agar and gelatin to which 2 per cent urea and 0.3 per cent ammonium carbonate were added. He was unable to obtain growth of the organism in urea peptone solutions unless Chapoteau peptone, which was used by Miquel, was employed. Simple media containing, in addition to urea, asparagine and glucose, or ammonium salts of organic acids, did not support growth. Lohnis and Kuntze (1908) used bouillon, agar, and gelatin, each containi g 2 per cent urea, for the culti-vation of the organism, and confirmed Beijerinck's observations concerning the unsuitability of media which contained no urea or protein. It became generally accepted that the most important criterion for the recognition of B. Pasteuri was its inability to grow on ordinary media without added urea. Later work by Viehoever (1913), however, cast doubt on the necessity for urea, and this author observed growth of the organism in much simpler media than those used by Beijerinck and L6hnis and Kuntze. Viehoever described good growth in an ammonium carbonate mineral solution containing glucose and asparagine as the only organic compounds. In the same medium without glucose the organism was still capable of growing, but less vigorously. Vie-hoever added either urea, ammonium carbonate, or sodium carbonate to all the media he used