Probing a novel allosteric binding site in Mycobacterium DNA gyrase to tackle TB and antimicrobial resistance

探索分枝杆菌 DNA 旋转酶中的新型变构结合位点以应对结核病和抗菌素耐药性

• 批准号: 2739699
• 金额: --
• 依托单位: University of Leeds
• 依托单位国家: 英国
• 项目类别: Studentship
• 财政年份: 2022
• 资助国家: 英国
• 起止时间: 2022 至 无数据
• 项目状态: 未结题
• 来源: https://gtr.ukri.org/projects?ref=studentship-2739699
• 关键词: Probing; novel; allosteric; binding; site

BackgroundAntimicrobial resistance (AMR) undermines the effectiveness of antibiotics. Fluoroquinolones are frontline antibiotics that treat bacterial infections via the inhibition of DNA gyrase. A recently characterised allosteric site on Staphylococcus aureus DNA gyrase offers the potential for the design of allosteric inhibitors of gyrase. Since the allosteric site is distinct from the fluoroquinolone-binding site, allosteric inhibitors can overcome fluoroquinolone resistance observed in the clinic (point mutations in gyrase). The project aims to investigate this allosteric site in Mycobacterium tuberculosis (Mtb) which has been unexplored to date, but has high amino acid conservation compared to the sequence of S. aureus gyrase.Objectives1. Use computational techniques and homology modelling to build a structural model of the Mtb allosteric site.2. Use computational medicinal chemistry to design potent inhibitors of Mtb.3. Ascertain the mode of action of the allosteric inhibitors: do they bind to the nicked or cleaved DNA complex?4. Establish synergy of allosteric inhibitors with fluoroquinolones.Novelty1.4 million people died of TB in 2019 and bovine TB is a major infectious disease in cattle. Multi-drug resistance (XDR)-TB are strains resistance to nearly all frontline antibiotics. Therefore, new investigations into viable therapeutic targets is required such as this allosteric site.TimelinessThis work capitalises on our recent discovery of Escherichia coli gyrase allosteric inhibitors with cellular activity against Mtb (MIC90 8 uM). The supervisory team have an established track record in investigating small molecule inhibition of bacterial DNA gyrase. All the methodologies for these studies have been established.Experimental ApproachThe student will be trained in computational medicinal chemistry (to understand protein structure, ligand-protein interactions, computer-aided drug design) and synthetic chemistry. Synthesised molecules will be characterized using a combination of biochemistry and crystallography to ascertain their mode of Mtb gyrase inhibition.

抗生素耐药性（AMR）破坏了抗生素的有效性。氟喹诺酮类药物是通过抑制DNA旋切酶治疗细菌感染的一线抗生素。最近表征的金黄色葡萄球菌DNA回转酶的变构位点为设计回转酶的变构抑制剂提供了潜力。由于变构位点不同于氟喹诺酮结合位点，因此变构抑制剂可以克服临床观察到的氟喹诺酮耐药性（gyrase点突变）。该项目旨在研究结核分枝杆菌（Mtb）中这一迄今尚未发现的变构位点，但与金黄色葡萄球菌（S. aureus gyrasse）序列相比，它具有较高的氨基酸保守性。利用计算技术和同源性建模建立Mtb变构位点的结构模型。利用计算药物化学设计有效的Mtb.3抑制剂。确定变构抑制剂的作用模式：它们是否与有缺口的或断裂的DNA复合物结合？2019年有140万人死于结核病，牛结核病是牛的一种主要传染病。多重耐药结核是指对几乎所有一线抗生素都具有耐药性的菌株。因此，需要对这种变构部位等可行的治疗靶点进行新的研究。这项工作利用了我们最近发现的具有抗结核分枝杆菌细胞活性的大肠杆菌回转酶变构抑制剂（MIC90 8 uM）。监督小组在研究细菌DNA旋切酶的小分子抑制方面有良好的记录。这些研究的所有方法都已确立。实验方法学生将学习计算药物化学（了解蛋白质结构，配体-蛋白质相互作用，计算机辅助药物设计）和合成化学。合成的分子将使用生物化学和晶体学相结合的方法进行表征，以确定它们的结核杆菌旋切酶抑制模式。