Tükenmez Hasan, Sarkar Souvik, Anoosheh Saber, Kruchanova Anastasiia, Edström Isabel, Harrison Gregory A, Stallings Christina L, Almqvist Fredrik, Larsson Christer
Department of Chemistry, Umeå University, 90187, Umeå, Sweden.
Department of Molecular Biology, Umeå University, 90187, Umeå, Sweden.
Sci Rep. 2021 Jan 15;11(1):1523. doi: 10.1038/s41598-021-81104-y.
Tuberculosis, caused by Mycobacterium tuberculosis (Mtb), is a major health threat listed among the top 10 causes of death worldwide. Treatment of multidrug-resistant Mtb requires use of additional second-line drugs that prolong the treatment process and result in higher death rates. Our team previously identified a 2-pyridone molecule (C10) that blocks tolerance to the first-line drug isoniazid at C10 concentrations that do not inhibit bacterial growth. Here, we discovered that the genes rv3160c and rv3161c are highly induced by C10, which led us to investigate them as potential targets. We show that Rv3160c acts as a TetR-like transcriptional repressor binding to a palindromic sequence located in the rv3161c promoter. We also demonstrate that C10 interacts with Rv3160c, inhibiting its binding to DNA. We deleted the rv3161c gene, coding for a putative oxygenase, to investigate its role in drug and stress sensitivity as well as C10 activity. This Δrv3161c strain was more tolerant to isoniazid and lysozyme than wild type Mtb. However, this tolerance could still be blocked by C10, suggesting that C10 functions independently of Rv3161c to influence isoniazid and lysozyme sensitivity.
由结核分枝杆菌（Mtb）引起的结核病是全球十大死因之一，对健康构成重大威胁。治疗耐多药结核分枝杆菌需要使用额外的二线药物，这会延长治疗过程并导致更高的死亡率。我们的团队之前鉴定出一种2-吡啶酮分子（C10），在不抑制细菌生长的C10浓度下，它能阻断对一线药物异烟肼的耐受性。在此，我们发现基因rv3160c和rv3161c被C10高度诱导，这促使我们将它们作为潜在靶点进行研究。我们表明，Rv3160c作为一种类似TetR的转录抑制因子，与位于rv3161c启动子中的回文序列结合。我们还证明，C10与Rv3160c相互作用，抑制其与DNA的结合。我们删除了编码假定加氧酶的rv3161c基因，以研究其在药物和应激敏感性以及C10活性中的作用。这种Δrv3161c菌株比野生型结核分枝杆菌对异烟肼和溶菌酶更具耐受性。然而，这种耐受性仍可被C10阻断，这表明C10独立于Rv3161c发挥作用，影响异烟肼和溶菌酶的敏感性。
