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Toxin/antitoxin (TA) systems have been scarcely studied in <i>Brucella abortus</i>, the causative agent of brucellosis, which is one of the most prevalent zoonotic diseases worldwide. In this study, the roles of a putative type II TA system composed by a Zinc-dependent metalloproteinase (ZnMP) and a transcriptional regulator HTH-Xre were evaluated. The deletion of the open reading frame (ORF) BAB1_0270, coding for ZnMP, used to produce a mutant strain, allowed us to evaluate the survival and gene expression of <i>B. abortus</i> 2308 under oxidative conditions. Our results showed that the <i>B. abortus</i> mutant strain exhibited a significantly reduced capacity to survive under hydrogen peroxide-induced oxidative stress. Furthermore, this mutant strain showed a decreased expression of genes coding for catalase (<i>kat</i>E), alkyl hydroperoxide reductase (<i>ahp</i>C) and transcriptional regulators (<i>oxy</i>R and <i>oxy</i>R-like), as well as genes involved in the general stress response, <i>phy</i>R and <i>rpo</i>E1, when compared to the wild-type strain. These findings suggest that this type II ZnMP/HTH-Xre TA system is required by <i>B. abortus</i> to resist oxidative stress. Additionally, previous evidence has demonstrated that this ZnMP also participates in the acidic stress resistance and virulence of <i>B. abortus</i> 2308. Therefore, we propose a hypothetical regulatory function for this ZnMP/HTH-Xre TA system, providing insight into the stress response and its potential roles in the pathogenesis of <i>B. abortus</i>.