Bacterial zinc uptake and regulators.

Klaus Hantke

doi:10.1016/j.mib.2005.02.001

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Bacterial zinc uptake and regulators.

Klaus Hantke

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Abstract

Many bacteria use an ABC transporter for high-affinity uptake of zinc with a cluster 9 solute-binding protein. Other members of this protein family transport manganese. At present, it is not always possible to distinguish zinc-specific and manganese-specific transporters on the basis of sequence analysis. Low-affinity ZIP-type zinc transporters in bacteria have also been identified. Most high-affinity zinc uptake systems are regulated by Zur proteins, which form at least three unrelated subgroups of the Fur protein family (regulators of iron transport). High-affinity transport of zinc out of the periplasmic space poses a problem to the cell because zinc is a cofactor of several periplasmic enzymes. Certain zinc-binding proteins in the periplasm might function as chaperones to supply these enzymes with zinc.

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ATP-Binding Cassette Transporters Amino Acid Sequence Bacteria Bacterial Proteins Biological Transport Gene Expression Regulation, Bacterial Molecular Sequence Data Repressor Proteins Zinc Journal Article Research Support, Non-U.S. Gov't Review

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Klaus Hantke. 2005. Bacterial zinc uptake and regulators.. https://doi.org/10.1016/j.mib.2005.02.001

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