Zinc homeostasis is crucial for the development and stress resistance of bacteria in the environment. Serial zinc sensing transcriptional regulators, zinc transporters and zinc binding proteins were found to maintain the zinc homeostasis in bacteria. Zur is a zinc uptake regulator that is widely distributed in species, and ZnuABC, as well as the Type VI Secretion System (T6SS4) function in zinc acquisition. Here, we report that the regulator Zur inhibits the expression of the ZnuABC which inhibition could be eliminated at low zinc level, and upregulates the T6SS4 operon in Yersinia pseudotuberculosis to facilitate Zn²⁺ uptake and oxidative stress resistance. Zur regulates the expression of ZnuABC and T6SS4 by directly binding to their promoter regions. Zur senses the Zn²⁺ concentration and represses ZnuABC in a Zn²⁺-containing environment. Zur works as an auxiliary regular activator of T6SS4, facilitating oxidative stress resistance. This study revealed the dual function of regulator Zur on ZnuABC and T6SS4, and enriched the knowledge of Zn²⁺ homeostasis maintenance in Y. pseudotuberculosis.

锌稳态对于环境中细菌的发育和抗逆性至关重要。发现连续的锌感应转录调节因子、锌转运蛋白和锌结合蛋白可以维持细菌中的锌稳态。Zur 是一种广泛分布于物种中的锌摄取调节剂，以及 ZnuABC 以及 VI 型分泌系统 (T6SS4) 在锌获取中的功能。在这里，我们报告调节剂 Zur 抑制 ZnuABC 的表达，这种抑制可以在低锌水平下消除，并上调假结核耶尔森氏菌中的 T6SS4 操纵子以促进 Zn ²⁺吸收和抗氧化应激。Zur 通过直接结合到它们的启动子区域来调节 ZnuABC 和 T6SS4 的表达。Zur 感应 Zn ²⁺在含Zn ²⁺的环境中浓缩并抑制 ZnuABC 。Zur 作为 T6SS4 的辅助常规激活剂，促进抗氧化应激。本研究揭示了调节剂Zur对ZnuABC和T6SS4的双重作用，丰富了对假结核耶尔森病中Zn ²⁺稳态维持的认识。