Mycobacterium tuberculosis, the causative agent of tuberculosis, possess flavin-dependent thymidylate synthase, ThyX. Since thyX is absent in humans and was shown to be essential for M. tuberculosis normal growth, ThyX is thought to be an attractive novel TB drug target. This study assessed thyX essentiality in Mycobacterium bovis BCG strains using CRISPR interference based gene silencing and found that thyX is not essential in an M. bovis BCG Tokyo derivative strain. A thyX deletion mutant strain was successfully constructed from that strain, which reinforces the non-essentiality of thyX under a certain genetic background.

中文翻译：

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在牛分枝杆菌 BCG 中进行 thyX 基因沉默和构建 thyX 缺失克隆的尝试

结核分枝杆菌是结核病的病原体，具有黄素依赖性胸苷酸合成酶 ThyX。由于thyX在人类中不存在并且被证明对M. tuberculosis正常生长至关重要，因此 ThyX 被认为是一种有吸引力的新型结核病药物靶标。本研究评估thyX必要性在牛分枝杆菌BCG菌株使用基于CRISPR干扰基因沉默和发现thyX不是必不可少的牛分枝杆菌BCG东京衍生菌株。甲thyX缺失突变体菌株已成功地从该菌株，其强化的非必要性构造thyX 在一定的遗传背景下。