Zinc-dependent regulation of zinc import and export genes by Zur
In most bacteria, zinc depletion is sensed by Zur, whereas the surplus is sensed by different regulators to achieve zinc homeostasis. Here we present evidence that zinc-bound Zur not only represses genes for zinc acquisition but also induces the zitB gene encoding a zinc exporter in Streptomyces coe...
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Published in | Nature communications Vol. 8; no. 1; p. 15812 |
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Main Authors | , , , , , |
Format | Journal Article |
Language | English |
Published |
London
Nature Publishing Group UK
09.06.2017
Nature Publishing Group Nature Portfolio |
Subjects | |
Online Access | Get full text |
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Summary: | In most bacteria, zinc depletion is sensed by Zur, whereas the surplus is sensed by different regulators to achieve zinc homeostasis. Here we present evidence that zinc-bound Zur not only represses genes for zinc acquisition but also induces the
zitB
gene encoding a zinc exporter in
Streptomyces coelicolor
, a model actinobacteria. Zinc-dependent gene regulation by Zur occurs in two phases. At sub-femtomolar zinc concentrations (phase I), dimeric Zur binds to the Zur-box motif immediately upstream of the
zitB
promoter, resulting in low
zitB
expression. At the same time, Zur represses genes for zinc uptake. At micromolar zinc concentrations (phase II), oligomeric Zur binding with footprint expansion upward from the Zur box results in high
zitB
induction. Our findings reveal a mode of zinc-dependent gene activation that uses a single metalloregulator to control genes for both uptake and export over a wide range of zinc concentrations.
Zinc homeostasis in most bacteria is achieved by a set of regulators, each responding to a certain level of intracellular zinc. Here the authors show that, in
Streptomyces coelicolor
, the Zur regulator modulates the expression of genes for zinc import and export over a large range of zinc concentrations. |
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Bibliography: | ObjectType-Article-1 SourceType-Scholarly Journals-1 ObjectType-Feature-2 content type line 23 These authors contributed equally to this work. |
ISSN: | 2041-1723 2041-1723 |
DOI: | 10.1038/ncomms15812 |