Construction of potent and specific inhibitors of M. tuberculosis redox enzymes using fragment screening methods

使用片段筛选方法构建结核分枝杆菌氧化还原酶的有效和特异性抑制剂

基本信息

批准号：
BB/R009961/1
负责人：
Andrew Munro
金额：
$ 53.3万
依托单位：
University of Manchester
依托单位国家：
英国
项目类别：
Research Grant
财政年份：
2018
资助国家：
英国
起止时间：
2018 至无数据
项目状态：
已结题

来源：
https://gtr.ukri.org/projects?ref=BB%2FR009961%2F1
关键词：
Construction potent specific inhibitors M.

项目摘要

Mycobacterium tuberculosis (Mtb) is a human pathogen that causes the debilitating disease tuberculosis (TB). Recent reports from the World Health Organization (WHO) indicated that one third of the world's population is infected with TB, and the WHO declared a "global emergency" due to the worldwide spread of Mtb and since several Mtb strains are resistant to antibiotics that once formed the basis of effective TB treatments. For instance, there are now many Mtb strains that are resistant to the leading drugs rifampicin and isoniazid - referred to a multidrug resistant (MDR) TB. Other strains are resistant to many other drugs (extensively drug resistant, or XDR TB), and some are resistant to all major TB drugs (totally drug resistant, or TDR TB). The development of resistance to drugs by Mtb is a natural phenomenon caused by random mutations of bacterial DNA that result in changes to structures of proteins that prevent them being inactivated by particular antibiotics. The issues of Mtb drug resistance faced today arise from the gradual development and spread of resistance to several TB drugs over many years. In the same time period (~1960s to 1990s) there were very few new TB drugs developed, which resulted in a dearth of effective TB antibiotics. While new drugs are now coming through the pipeline, there is still a shortage of effective TB drugs and there are other complicating factors - among which is the issue of TB patients being more susceptible to infection by HIV/AIDS and vice versa. To address this issue, our plan is to progress a novel route to the development of new drugs that can inhibit the activities of a group of enzymes (called P450s) which are known to be essential to the survival of Mtb bacteria and to their ability to sustain infection in their human host. While previous TB drugs have usually been selected by extensive screening of large libraries of complex chemicals, we will use instead a relatively new approach to development of new and effective drugs against Mtb. The process of fragment screening involves using relatively small libraries of chemicals of generally quite small size. These libraries of chemicals are mixed with the proposed enzyme targets (the P450s) and in cases where different "fragments" bind to the P450s, this will be detected by methods including changes to the thermal stability of the proteins. With knowledge that selected fragment bind the P450s, the three dimensional structures of the proteins will be determined using the technique of X-ray crystallography, which will also reveal exactly where fragments bind within the P450s. This information is essential for the further development of the fragment screening process, since once the binding positions of a number of the chemical fragments inside the P450s are known a strategy can be developed to use chemistry approaches to link fragments bound in adjacent positions in order to make larger compounds that show much better selectivity for the particular P450 enzyme. Cycles of chemical "improvement" are usually needed, but these can lead to very effective antibiotic drugs. Our plan is to use this fragment screening and development programme on Mtb P450s essential for survival of Mtb (a P450 called CYP121A1), for its ability to survive in the lungs by using human cholesterol (CYPs 124A1, 125A and 142A1), and for its ability to infect and spread (called virulence, CYP128A1). The antibiotic drugs developed against each of these Mtb P450 proteins will be optimized for tight binding to their targets, and then their ability to terminate growth of Mtb/kill the bacterium will be verified by testing the inhibitors directly against the bacterial pathogen. Further important studies will look at the responses of Mtb to treatment with these inhibitors - in particular looking for changes in the profile of chemicals the bacteria produces in order to understand how the inhibitors affect the Mtb and to enable improvements in inhibitor effectiveness.

结核分枝杆菌（MTB）是一种人类病原体，会导致令人衰弱的疾病结核病（TB）。世界卫生组织（WHO）的最新报道表明，由于MTB的全球传播，世界三分之一的人口感染了结核病，而WHO宣布了“全球紧急情况”，并且由于几种MTB菌株对曾经形成有效TB治疗的基础的抗生素具有抗性。例如，现在有许多MTB菌株对主要药物利福平和异念珠菌具有抗性 - 称为多药耐药（MDR）TB。其他菌株对许多其他药物（广泛的耐药性或XDR TB）具有抗药性，并且有些抗性对所有主要TB药物（完全耐药性或TDR TB）具有抗性。 MTB对药物的耐药性的发展是由细菌DNA的随机突变引起的一种自然现象，导致蛋白质结构的变化，以防止它们被特定的抗生素灭活。今天面临的MTB耐药性问题是由于多年来对几种结核病药物的抗药性逐渐发展和传播。在同一时期（1960年代至1990年代）中，很少有新的结核病药物产生，从而缺乏有效的结核病抗生素。尽管新药正在通过管道来源，但仍然缺乏有效的结核病药物，还有其他复杂因素 - 其中TB患者更容易受到HIV/AIDS感染，反之亦然。为了解决这个问题，我们的计划是发展新药物的新途径，该途径可以抑制一组酶（称为P450S）的活性，这些酶对MTB细菌的生存至关重要，并在其人类宿主中维持感染的能力。虽然通常通过对大型复杂化学物质文库进行广泛筛选以前的结核病药物，但我们将使用一种相对较新的方法来开发针对MTB的新有效药物。碎片筛选的过程涉及使用相对较小的化学物质库通常很小。这些化学物质的文库与所提出的酶靶标（P450）混合，并且在不同的“片段”与P450结合的情况下，这将通过包括蛋白质热稳定性的方法（包括变化）检测到。知道所选片段结合p450s的知识，将使用X射线晶体学技术确定蛋白质的三维结构，该技术还将准确揭示片段在P450中结合的位置。该信息对于片段筛选过程的进一步发展至关重要，因为一旦已知P450中许多化学片段的结合位置，就可以制定使用化学方法将绑定在相邻位置上的片段联系起来的策略，以使较大的化合物对特定P450酶的选择性更好地选择性。通常需要化学“改进”的周期，但这可能导致非常有效的抗生素药物。我们的计划是在MTB P450上使用MTB生存至关重要的碎片筛选和开发计划（称为CYP121A1），因为它通过使用人胆固醇（CYPS 124A1、125A和142A1）在肺中生存的能力，以及它能够感染和扩散（称为Virulitence，CIPS128A）。针对这些MTB P450蛋白中每一种开发的抗生素药物将被优化，以与其靶标紧密结合，然后将其终止MTB/杀死细菌生长的能力通过直接测试抑制剂对细菌病原体进行测试。进一步的重要研究将研究MTB对这些抑制剂治疗的反应 - 特别是寻找细菌产生的化学物质谱的变化，以了解抑制剂如何影响MTB并能够改善抑制剂效率。

项目成果

期刊论文数量（9）

专著数量（0）

科研奖励数量（0）

会议论文数量（0）

专利数量（0）

A new strategy for hit generation: Novel in cellulo active inhibitors of CYP121A1 from Mycobacterium tuberculosis via a combined X-ray crystallographic and phenotypic screening approach (XP screen).

DOI：
10.1016/j.ejmech.2022.114105
发表时间：
2022-02-15
期刊：
European journal of medicinal chemistry
影响因子：
6.7
作者：
Frederickson M;Selvam IR;Evangelopoulos D;McLean KJ;Katariya MM;Tunnicliffe RB;Campbell B;Kavanagh ME;Charoensutthivarakul S;Blankley RT;Levy CW;de Carvalho LPS;Leys D;Munro AW;Coyne AG;Abell C
通讯作者：
Abell C

Cytochrome P450 1A1 opens up to new substrates.

细胞色素 P450 1A1 开辟了新的底物。