Relation of Salmonella typhi and Salmonella gallinarum auxotrophicity to the ability to grow on Simmons' medium

A total of 9 S. typhi strains and 1 S. gallinarum strain isolated from clinical material are auxotrophic with respect to tryptophan. The growth of S. typhi is accelerated in a glucose- and tryptophan-containing minimal medium with cysteine and methionine added. S. typhi strains are incapable of using sodium citrate as the only source of carbon. S. typhi cannot grow on Simmons citrate agar as these organisms are auxotrophic with respect to tryptophan and incapable of using sodium citrate as the only source of carbon, and S. gallinarum cannot grow on this medium as they are auxotrophic with respect to tryptophan.