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. 1996 May;178(9):2712–2714. doi: 10.1128/jb.178.9.2712-2714.1996

Intracellular inducer Hg2+ concentration is rate determining for the expression of the mercury-resistance operon in cells.

H Yu 1, L Chu 1, T K Misra 1
PMCID: PMC178000  PMID: 8626343

Abstract

Experiments involving mercury resistance mer operon-lacZ fusions, point mutations in the mercuric ion reductase merA gene, and transcomplementation have revealed that in Hg2+-resistant cells, the inducer Hg2+ concentration is rate determining for activation of transcription. mer operon expression is activated by the presence of nanomolar concentrations of Hg2+ in liquid media only when the mercuric ion reductase function is artificially inactivated in cells, whereas cells with active mercuric ion reductase require micromolar concentrations of Hg2+ for effective induction of the operon.

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Selected References

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