The central component of a metal-responsive genetic switch, the MerR
نویسنده
چکیده
The central component of a metal-responsive genetic switch, the MerR metalloregulatory protein, is one of the first examples of an mtracellular heavy metal receptor [l]. The merR gene product mediates the induction of the mercury resistance phenotype in bacteria [21, and resistant cells respond to subtoxic Hg(I1) levels (10 *6 -lo8 M) with transcriptional activation of the mer operon [31. Genetic evidence indicates that the merR gene product, MerR, exerts negative control of the structural genes in the absence of HgUI), and positive control in the presence of Hg(I1) 133.
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