Abstract
Thebgl operon ofEscherichia coli, which encodes the genes necessary for transport and catabolism of β-glucosides, is silent in wild-type cells and is activated by the transposition of IS elements. The silent form of the operon appears to be the stable state. We isolated Bgl- revertants of an activated strain after growth under nonselective conditions to understand whether activation of the cryptic operon by IS elements is reversible. Genetic and molecular analyses revealed that a majority of revertants carry deletions of thebgl structural genes, indicating that an irreversible alteration has occurred in the operon. Implications of these results for the evolution and maintenance of cryptic genes are discussed. [Yakkundi A., Moorthy S. and Mahadevan S. 1998 Reversion of anE. coli strain carrying an IS1-activatedbgl operon under nonselective conditions is predominantly due to deletions within the structural genes.J. Genet. 77, 21–26]
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Yakkundi, A., Moorthy, S. & Mahadevan, S. Reversion of anE. coli strain carrying an IS1-activatedbgl operon under nonselective conditions is predominantly due to deletions within the structural genes. J. Genet. 77, 21–26 (1998). https://doi.org/10.1007/BF02933037
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DOI: https://doi.org/10.1007/BF02933037