Behind the Shield of Czc: ZntR Controls Expression of the Gene for the Zinc-Exporting P-Type ATPase ZntA in<i>Cupriavidus metallidurans</i>
Vladislava Schulz, Christopher Schmidt-Vogler, Phillip Strohmeyer, Stefanie Weber, Daniel Kleemann, Dietrich H. Nies, Martin Herzberg
Abstract
Zinc is an essential metal for numerous organisms from humans to bacteria. The transportome of zinc uptake and efflux systems controls the overall cellular composition and zinc content in a double feed-back loop. Zinc starvation mediates, via the Zur regulator, an up-regulation of the zinc import capacity via the ZIP-type zinc importer ZupT and an amplification of zinc storage capacity, which together raise the cellular zinc content again. On the other hand, an increasing zinc content leads to ZntR-mediated up-regulation of the zinc efflux system ZntA, which decreases the zinc content. Together, the Zur regulon components and ZntR/ZntA balance the cellular zinc content under both high external zinc concentrations and zinc starvation conditions.