ENZYMATIC DEADAPTATION

Abstract

Beta-Galacto-sidase of Escherichia coli, adapted to lactose, was studied during enzymatic deadaptation. Lactose grown cultures were subcultured in the absence of lactose under a variety of conditions. Deadaptation consisted of dilution, rather than destruction, of preformed beta-galactosidase. Amino acid auxotrophs were unable to form beta-galactosidase unless supplied with the corresponding amino acids. It is suggested that the enzyme beta-galactosidase may not be unique in its stability.