The metal permease ZupT from Escherichia coli is a transporter with a broad substrate spectrum
The metal permease ZupT from Escherichia coli is a transporter with a broad substrate spectrum
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DOI：
10.1128/jb.187.5.1604-1611.2005
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发表时间：
2005-03-01
影响因子：
3.2
通讯作者：
Rensing, C
中科院分区：
文献类型：
--
作者：
Grass, G;Franke, S;Rensing, C
大肠杆菌zupT（以前的ygiE）基因编码与二价金属离子转运蛋白的真核ZIP家族成员相关的细胞质膜蛋白（ZupT）。以前，ZupT被证明是负责锌的吸收。在这项研究中，我们表明，ZupT是一种二价金属阳离子转运蛋白的广泛底物特异性。大肠在所有已知的铁摄取系统中具有破坏的大肠杆菌菌株只有在表达zupT时才能在螯合剂存在下生长。拟南芥ZIP 1的异源表达也能缓解该E.大肠杆菌菌株，如可以表达土著mntH或feoABC。完整细胞的转运研究表明，ZupT促进Fe-55（2+）的吸收类似于MntH或FeO的吸收。其他二价阳离子也被ZupT吸收，如使用（CO2+）-C-57所示。zupT在E. coli细胞对Co ~（2+）敏感，对Mn ~（2+）敏感。ZupT似乎不受金属调节：phi（zupT-lacZ）操纵子融合体的表达表明zupT以低水平组成型表达。
The Escherichia coli zupT (formerly ygiE) gene encodes a cytoplasmic membrane protein (ZupT) related to members of the eukaryotic ZIP family of divalent metal ion transporters. Previously, ZupT was shown to be responsible for uptake of zinc. In this study, we show that ZupT is a divalent metal cation transporter of broad substrate specificity. An E. coli strain with a disruption in all known iron uptake systems could grow in the presence of chelators only if zupT was expressed. Heterologous expression of Arabidopsis thaliana ZIP1 could also alleviate iron deficiency in this E. coli strain, as could expression of indigenous mntH or feoABC. Transport studies with intact cells showed that ZupT facilitates uptake of Fe-55(2+) similarly to uptake of MntH or Feo. Other divalent cations were also taken up by ZupT, as shown Using (CO2+)-C-57. Expression of zupT rendered E. coli cells hypersensitive to Co2+ and sensitive to Mn2+. ZupT did not appear to be metal regulated: expression of a phi(zupT-lacZ) operon fusion indicated that zupT is expressed constitutively at a low level.