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J Bacteriol. 1983 January; 153(1): 562–565.
PMCID: PMC217411

Phenotypic reversal in dam mutants of Escherichia coli K-12 by a recombinant plasmid containing the dam+ gene.


A recombinant plasmid, pMQ3, carrying the dam gene of Escherichia coli K-12, was constructed and transformed into dam+ and dam- strains. Both dam- and dam+ strains containing pMQ3 showed a wild phenotype for all traits, including mutation rate, except for a 10-fold increase in DNA adenine methylase activity.

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Selected References

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