zur: a Zn(2+)-responsive regulatory element of Staphylococcus aureus.

A putative operon encoding a probable zinc-responsive regulatory element (zur) and components of an ABC-type transporter (mreA mreB) have been characterized in Staphylococcus aureus. The zur gene was inactivated but apparently this did not alter Zn(2+) uptake. Expression of mreAB zur is at a low level under a range of ion conditions. To allow inducible expression of the operon, a construct was made placing it under the control of the IPTG-inducible P(spac) promoter. Using this approach, it was shown that zur is able to repress expression of the entire operon in a Zn(2+)-dependent manner, and that mreA and mreB are likely to be involved in high-affinity ion uptake. zur has no apparent role in pathogenicity in a lesion model of S. aureus infection.