MUTATION TO l-RHAMNOSE RESISTANCE AND TRANSDUCTION TO l-RHAMNOSE UTILIZATION IN SALMONELLA TYPHOSA,

Salmonella typhosa is unable to utilize L-rhamnose as a carbon and energy source for growth. When rhamnose is added to a nutrient agar medium (or other similar media), which otherwise supports growth of this organism, growth is reportedly partially inhibited, and rhamnose resistant papillae arise (Muller, 1911). These mutants, which are no longer inhibited by rhamnose, and which no longer papillate on rhamnose nutrient agar, are still similar to the parent strain in being unable to utilize rhamnose as a carbon and energy source, produce acid or gas from rhamnose, or oxidize rhamnose (Mutller, 1911; Barkulis, 1949). Thus this mutational phenomenon differs from that of Escherichia coli mutabile, where papillae formed on lactose media produce acid and gas from lactose and utilize lactose as a carbon and energy source. Salmonella typhimurium, on the other hand, is able to utilize rhamnose as a carbon and energ