Discovery of Phospopantetheinyl Transferse Inhibitors Against Mycobacterium tuberculosis

抗结核分枝杆菌磷酸泛酰基转移酶抑制剂的发现

• 批准号: 10450109
• 负责人: Jeffrey Aube
• 金额: $ 77.99万
• 依托单位: UNIV OF NORTH CAROLINA CHAPEL HILL
• 依托单位国家: 美国
• 财政年份: 2021
• 资助国家: 美国
• 起止时间: 2021-07-13 至 2025-06-30
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10450109
• 关键词: Age; Anabolism; Antimycobacterial Agents; Antitubercular Agents; Back; Biochemical; Biological Assay; Cardiotoxicity; Carrier Proteins; Chemicals; Client; Clinic; Clinical; Collaborations; Complement; Critiques; Crystallization; Disease; Drug Kinetics; Drug resistance; Fatty Acids; Foundations; Goals; Growth; Health Personnel; In Vitro; Knock-out; Laboratories; Lead; Length; Mammalian Cell; Measurement; Mediating; Medical; Medicine; Metabolic; Microsomes; Modeling; Mus; Mycobacterium tuberculosis; Organism; Orthologous Gene; Persons; Pharmaceutical Preparations; Property; Protocols documentation; Reporting; Resistance; Resolution; Rifampin; Safety; Science; Series; Sodium Channel; Structure; Structure-Activity Relationship; Therapeutic; Therapeutic Agents; Treatment Protocols; Tuberculosis; Variant; Virulence Factors; Work; X-Ray Crystallography; analog; design; drug candidate; drug-sensitive; extensive drug resistance; high throughput screening; in silico; in vivo; inhibitor; knock-down; macrophage; metabolomics; mycobacterial; novel; novel therapeutics; phosphopantetheinyl transferase; physical property; pre-clinical; preclinical development; programs; rational design; response; scaffold; synergism; tuberculosis drugs; tuberculosis treatment

Abstract Tuberculosis (TB) presents an ongoing global challenge to medical science that will only be met by multiple approaches. Due to the length of even “routine” TB therapy and the age of existing drugs – which contributes to the emergence of devastating resistant forms of the disease – the discovery of new drugs, especially those that function by new mechanisms of action, has become critical. In early 2019, a team including the present laboratory reported AU 8918 as the first high-quality inhibitor of 4'-phosphopantetheinyl transferase (PptT). PptT, which catalyzes the placement of a 4'-phosphopantetheinyl moiety onto a client carrier protein, is essential for the biosynthesis of mycobacterial fatty acids and virulence factors. PptT represents a valuable anti-TB target because (1) it is essential for mycobacterial tuberculosis (Mtb) survival in vitro and in mice, (2) it is divergent from the closest host ortholog, and (3) it is distinct from all targets of established TB drugs. In addition, its inhibition has been shown (4) to effectively kill Mtb including multi- and extensively-drug-resistant variants and (5) to block Mtb growth in mice, while (6) sparing other bacterial or mammalian cells. The primary hit compound, AU 8918, has an IC50 of 2.3 M in biochemical assays of PptT inhibition, a MIC90 of 3.1 M against Mtb in vitro, and has some physical properties features consistent with advancement as a drug candidate, but suffers from off-target cardiotoxicity likely associated with sodium channel blockade. The present proposal seeks to support an ongoing collaboration between three laboratories that share the common goal to design, synthesize, and characterize PptT inhibitors suitable for pre-clinical development. The availability of five high resolution co-crystal structures of AU 8918 and analogs bound to Mtb PptT has been leveraged to establish a robust in silico modeling protocol for the preliminary assessment of analogs. Several avenues to create novel PptT inhibitors are proposed, including (1) SAR exploration of AU 8918, (2) discovery and exploration of new scaffolds arising from bioisosteric replacements of the amidinourea subunit of AU 8918, and (3) new hits arising from an ongoing screen against PptT. We will characterize inhibitors by (1) biochemical PptT inhibition, (2) X-ray crystallography of inhibitor•PptT co-crystals, and (3) advanced biochemical characterization (including intracellular macrophage activity measurements, verification of on-target activity by knockdown/knockout studies, safety profiling against off-target liabilities, pharmacokinetic and metabolic characterization, metabolomics, and synergy studies). The final goal of the project is to identify 1–2 advanced compounds for advancement to in vivo studies in Mtb infected mice, having the following properties: (<0.1 M potency against PptT, <1 M MIC90 against Mtb, retention of positive physical properties, and lacking cardiotoxicity or activity (>30 M inhibition) at relevant Ca and Na channels.

抽象的 结核病（TB）提出了对医学科学的持续全球挑战 方法。由于“常规”结核病疗法的长度和现有药物的年龄，这有助于 疾病毁灭性形式的出现 - 发现新药，尤其是那些 通过新的作用机理的功能变得至关重要。 2019年初，包括当前实验室在内的团队 报道了AU 8918是4'-磷酸乙基转移酶（PPTT）的第一个高质量抑制剂。 pptt，哪个 催化4'-磷酸乙烯基部分放置在客户载体蛋白上，对于 分枝杆菌脂肪酸和病毒因子的生物合成。 PPTT代表有价值的抗TB目标 因为（1）这对于分枝杆菌结核（MTB）在体外和小鼠中生存至关重要，（2）它是不同的 从最接近的宿主直系同源物中，（3）它与已建立的结核病药物的所有靶标不同。另外，它 已显示抑制（4）有效地杀死了MTB，包括多种和广泛的药物抗性变体和 （5）阻止小鼠MTB的生长，而（6）保留其他细菌或哺乳动物细胞。主要的命中化合物， Au 8918，在PPTT抑制的生化测定中，IC50为2.3 r，MIC 90属于3.1°M的MIC在体外对MTB的MIC 90， 并且具有与候选药物的进步一致的一些物理特性，但遭受了 脱靶心脏毒性可能与钠通道阻滞有关。 本提案旨在支持三个共享的三个实验室之间的持续合作 设计，合成和表征适合临床前开发的PPTT抑制剂的共同目标。这 AU 8918和与MTB PPTT的类似物的五个高分辨率共结构结构的可用性已 杠杆以建立有力的硅建模方案，用于对类似物的初步评估。一些 提出了创建新型PPTT抑制剂的途径，包括（1）SAR探索AU 8918，（2）发现 以及探索由Au 8918的Amidinourea亚基的生物酶替代品引起的新脚手架的探索 （3）持续针对PPTT的屏幕引起的新命中。我们将通过（1）生化表征抑制剂 PPTT抑制作用，（2）抑制剂的X射线晶体学•PPTT共晶和（3）晚期生化 表征（包括细胞内巨噬细胞活性测量，验证靶向活性 敲低/淘汰研究，针对脱靶负债的安全分析，药代动力学和代谢 表征，代谢组学和协同研究）。该项目的最终目标是确定1-2高级 具有以下特性的MTB感染小鼠的体内研究的化合物：（ <0.1M 反对PPTT的效力，<1MMIC90针对MTB，阳性物理特性的保留和缺乏 在相关的Ca和Na通道处的心脏毒性或活性（> 30 r抑制）。