ZntB Is a Novel Zn <sup>2+</sup> Transporter in <i>Salmonella enterica</i> Serovar Typhimurium

Journal of Bacteriology - Tập 184 Số 16 - Trang 4369-4373 - 2002
Ashley J. Worlock1, Ronald L. Smith1
1Department of Biology, The University of Texas at Arlington, Arlington, Texas 76019

Tóm tắt

ABSTRACT A Zn 2+ transport system encoded by the zntB locus of Salmonella enterica serovar Typhimurium has been identified. The protein encoded by this locus is homologous to the CorA family of Mg 2+ transport proteins and is widely distributed among the eubacteria. Mutations at zntB confer an increased sensitivity to the cytotoxic effects of Zn 2+ and Cd 2+ , a phenotype that suggests that the encoded protein mediates the efflux of both cations. A direct analysis of transport activity identified a capacity for Zn 2+ efflux. These data identify ZntB as a zinc efflux pathway in the enteric bacteria and assign a new function to the CorA family of cation transporters.

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