Effect of Amino Acid Imbalance on Course of Lansing Poliomyelitis in Mice. ∗

Summary

1. A decreased susceptibility to Lansing poliomyelitis, characterized by prolonged incubation and survival times, has been observed in mice fed excess methionine. To obtain this effect fully, a continuous period of high methionine intake was necessary prior to inoculation. 2. The addition of excess methionine to low tryptophan rations containing 6-methyl tryptophan resulted in a more marked protection against Lansing infection in mice than when the same amounts of methionine or 6-methyl tryptophan were fed alone.