Studies on nutritional requirements of bacteria. IV. Nitrogen requirement of wild type Shigella dysenteriae and the effect of niacin thereon.

therefore, that the medium exerts no effect on•g traing•h . Sort and quantity of nitrogen sources None of those 10 strains could grow in the rmedium containing Lglutamlc acid, L-aspartic acid and L-methionlne (2). Upon examining the nitrogen requirement of about 60 wild Flexner type dysentery bacilli , even the most exacting strains of which were found to grow in the medium containing L-glutamic acid, L-aspartic acid, L-methionine , L-tryptophane, and L-cystine. It was found that the 10 strains of Shiga dysentery bacilli described above could be also grown in this medium . Each amino acid was withheld in turn from this medium and the growth was observed . Sorts and quantities of nitrogen sources tested were described in Table 1.