Certain constitutive mutations in the two regulator genes for alkaline phosphatase respond to an external suppressor. This result suggests that the products of the regulator genes, and therefore the repressor for alkaline phosphatase, are protein molecules. © 1963, Academic Press Inc. (London) Ltd.. All rights reserved.
Garen, A., & Garen, S. (1963). Genetic evidence on the nature of the repressor for alkaline phosphatase in E. coli. Journal of Molecular Biology, 6(5), 433–438. https://doi.org/10.1016/S0022-2836(63)80054-6