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. 1978 Dec;90(4):673-81.
doi: 10.1093/genetics/90.4.673.

Regulation of newly evolved enzymes. IV. Directed evolution of the Ebg repressor

B G Hall

Regulation of newly evolved enzymes. IV. Directed evolution of the Ebg repressor

B G Hall. Genetics. 1978 Dec.

Abstract

In Escherichia coli, the wild-type repressor of ebg (evolved beta-galactosidase) enzyme synthesis, specified by the ebgR+ gene, responds very weakly to lactulose (fructose-beta-D-galactopyranoside). Selection for a functional repressor that responds strongly to lactulose as an inducer reveals the existence of ebgR+L mutants, which occur spontaneously at a frequency of about 2 X 10(-10) . EBGR+L mutants are pleiotropic in that they specify ebg repressor with a greatly increased response to lactulose, lactose, galactose-arabinoside and methyl-galactoside as inducers. Selection of ebgR+L mutants is discussed within the framework of directed evolution of a regulatory function.

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References

    1. Science. 1964 Dec 4;146(3649):1313-5 - PubMed
    1. Proc Natl Acad Sci U S A. 1974 Jun;71(6):2453-5 - PubMed
    1. Annu Rev Microbiol. 1970;24:429-62 - PubMed
    1. J Bacteriol. 1971 Apr;106(1):90-6 - PubMed
    1. J Gen Microbiol. 1967 Apr;47(1):87-102 - PubMed