The effect of nitrite on nitratase adaptation inE. coli

Summary

• 1. Nitratase adaptation inE. coli is inhibited by ca. 6×10⁻³ M nitrite at pH 7.2.

• 2. The degree of inhibition is more closely related to the concentration of unionized nitrous acid than to the total nitrite concentration.

• 3. Since conditions allowing adaptation also favour nitrite production, nitratase adaptation must be auto-inhibitory.

• 4. The inhibitory effect of nitrite on growth, which parallels that on adaptation, is probably a general one on protein synthesis.

• 5. The stimulatory action of amino acids on the adaptation is not due to the destruction of nitrite.