Hypersensitivity to Hg2+ and hyperbinding activity associated with cloned fragments of the mercurial resistance operon of plasmid NR1
Hypersensitivity to Hg2+ and hyperbinding activity associated with cloned fragments of the mercurial resistance operon of plasmid NR1
复制标题
对 Hg2 过敏以及与质粒 NR1 耐汞操纵子克隆片段相关的超结合活性
DOI：
10.1128/jb.140.1.161-166.1979
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发表时间：
1979
影响因子：
3.2
通讯作者：
R. Rownd
中科院分区：
文献类型：
--
作者：
H. Nakahara;S. Silver;T. Miki;R. Rownd
质粒NR 1中与抗Hg 2+和有机汞有关的区域由限制性内切酶片段EcoRI-H和EcoRI-I上的序列组成。当这两个片段一起克隆到一个衍生物的质粒ColE 1，杂交质粒赋予的属性与那些父母的质粒，NR 1：抗汞2+和有机汞剂的溴化汞和荧光素乙酸汞和诱导合成的酶汞还原酶没有区别。当EcoRI-I片段克隆到质粒ColE 1中时，含有质粒的细胞与无质粒的菌株一样对Hg 2+和有机汞敏感。将EcoRI-H片段克隆到ColE 1中，发现含有该杂交质粒的细胞对Hg ~（2+）和有机汞过敏。这种超敏反应可通过先前暴露于低、亚毒性汞2+或红溴红水平而诱导。它与可诱导的超结合活性相关，该活性归因于控制Hg 2+摄取的基因，并在片段EcoRI-H上发现（其中包含抗汞[mer]操纵子的近端部分）。
The region of plasmid NR1 concerned with resistance to Hg2+ and organomercurials consists of sequences found on restriction endonuclease fragments EcoRI-H and EcoRI-I. When both fragments were cloned together into a derivative of plasmid ColE1, the hybrid plasmid conferred properties indistinguishable from those of the parental plasmid, NR1: resistance to Hg2+ and to the organomercurials merbromin and fluoresceinmercuric acetate and the inducible synthesis of the enzyme mercuric reductase. When fragment EcoRI-I was cloned into plasmid ColE1, cells containing the plasmid was as sensitive to Hg2+ and organomercurials as plasmidless strains. When fragment EcoRI-H was cloned into ColE1, cells with the hybrid plasmid were hypersensitive to Hg2+ and organomercurials. This hypersensitivity was inducible by prior exposure to low, subtoxic Hg2+ or merbromin levels. It was associated with an inducible hyperbinding activity attributed to a gene governing Hg2+ uptake and found on fragment EcoRI-H (which contains the proximal portion of a mercuric resistance [mer] operon).