Therapeutics for Drug-Resistant Bacteria: Pseudouridimycins

耐药细菌的治疗方法：假尿嘧啶霉素

基本信息

批准号：
8978290
负责人：
RICHARD H. EBRIGHT
金额：
$ 102.17万
依托单位：
RUTGERS, THE STATE UNIV OF N.J.
依托单位国家：
美国
项目类别：
财政年份：
2013
资助国家：
美国
起止时间：
2013-01-15 至 2017-12-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/8978290
关键词：
Address Animal Model Anti-Bacterial Agents Bacterial Infections Bacterial RNA Binding Sites Biological Availability Cells Complex DNA-Directed RNA Polymerase Dipeptides Drug Kinetics Drug resistance Drug-sensitive Engineering Exhibits Fermentation Genus staphylococcus Glutamine Growth Health Hemophilus In Vitro Infection Kilogram Macrolide-resistance Mammalian Cell Maximum Tolerated Dose Methicillin Resistance Moraxella Multi-Drug Resistance Neisseria Penicillin Resistance Procedures Production Property Public Health RNA Polymerase Inhibitor Resistance Resistance development Rifampin Rodent Safety Site Streptococcal Infections Streptococcus Streptomyces Structure Technology Transfer Testing Therapeutic Toxicity Tests Transcription Elongation Transcription Initiation Water Work analog base biodefense cost cytotoxicity design drug candidate drug resistant bacteria efficacy testing fitness glycylglutamine in vivo inhibitor/antagonist interfacial large scale production mouse model novel therapeutics nucleoside analog pathogen physical property resistance frequency

项目摘要

DESCRIPTION (provided by applicant): We have discovered the first nucleoside-analog inhibitor (NAI) that selectively inhibits bacterial RNA polymerase (RNAP): pseudouridimycin (PUM). PUM is produced by Streptomyces sp. NAI38640 and comprises a guanidinylated, N-hydroxylated Gly-Gln dipeptide conjugated to 5'-amino-pseudoridine. PUM inhibits bacterial RNAP--but not mammalian RNAP--in vitro, inhibits bacterial growth in culture, and potently clears infection in a mouse model of Group A Streptococcus infection (ED50 = 10 mg/kg). The compound exhibits antibacterial activity against a broad spectrum of drug-sensitive and drug-resistant bacterial pathogens, including drug-sensitive, penicillin-resistant, macrolide-resistant, and multi-drug-resistant Streptococci, drug-sensitive, methicillin-resistant, and multi-drug-resistant Staphylococci, Neisseria sp., Haemophilus sp., and Moraxella sp. The compound exhibits no cross-resistance with rifampin, the RNAP inhibitor in current use in broad-spectrum antibacterial therapy, and exhibits a spontaneous resistance frequency <1/10 that of rifampin. The compound exhibits additive antibacterial activity upon co-administration with rifampin. We have defined the binding site on RNAP for PUM (the "i+1" NTP insertion site) and the mechanism of inhibition of RNAP by PUM (competition with UTP for occupancy of the "i+1" NTP insertion site). The binding site and mechanism have no overlap with the binding site and mechanism of the RNAP inhibitor rifampin, consistent with the absence of cross-resistance with rifampin. We have determined a crystal structure of RNAP in complex with PUM. The crystal structure suggests specific alterations to the structure of PUM that are expected to increase potency against a broad spectrum of bacterial RNAP, exploiting structural features that are invariant in bacterial RNAP. We have developed procedures for semi-synthesis and total synthesis of PUM analogs. We propose to leverage the mechanistic information, structural information, and synthetic procedures obtained in preliminary work in order to design, synthesize, and evaluate PUM analogs having increased efficacy against a broad spectrum of drug-resistant and drug-resistant bacterial pathogens. Analogs will be evaluated for inhibition of RNAP in vitro, antibacterial activity in culture, cytotoxicity against mammalian cells in culture, resistance properties in culture, and physical properties. Analogs of high promise will be evaluated for antibacterial efficacy in small-animal models of infection, and analogs of highest promise will be evaluated for bioavailability, pharmacokinetics, safety, and ability to scale synthesis.

描述（由申请人提供）：我们发现了第一个有选择地抑制细菌RNA聚合酶（RNAP）的核苷 - 氨基酸抑制剂（NAI）：假霉菌素（PUM）。 PUM由链霉菌Sp。产生。 NAI38640并包含鸟嘌呤的，N-羟基化的Gly-Gln二肽，共轭到5'-氨基 - 二十烷。 PUM抑制细菌RNAP-但不是哺乳动物RNAP-在体外，可以抑制培养细菌的生长，并在A组链球菌感染的小鼠模型中有效清除感染（ED50 = 10 mg/kg）。该化合物对广泛的药物敏感和抗药性细菌病原体表现出抗菌活性，包括药物敏感的，耐青霉素的，耐大花生素的病原体，以及多药抗药性链球菌，对药物敏感，耐甲氧西林和多药耐药的葡萄球菌，奈瑟氏菌Sp。，Heamophilus sp。和Moraxella sp。该化合物与利福平（RNAP抑制剂）在当前在广谱抗菌治疗中的使用中没有抗抗性，并且表现出自发性抗性频率<1/10 rifampin。与利福平共同给药后，该化合物表现出添加剂抗菌活性。我们已经在RNAP上定义了PUM（“ I+1” NTP插入位点）和通过PUM抑制RNAP的机制（与UTP竞争“ I+1” NTP插入位点占用）。结合位点和机制与RNAP抑制剂利福平的结合位点和机制无重叠，这与不存在与利福平交叉耐药性一致。我们已经确定了与PUM复合物中RNAP的晶体结构。晶体结构提出了对脓液结构的特定改变，这些改变有望增加针对细菌RNAP的效力，从而利用细菌RNAP中不变的结构特征。我们已经开发了半合成和PUM类似物总合成的程序。我们建议在初步工作中获得的机械信息，结构信息和合成程序，以设计，合成和评估对广泛的耐药和耐药细菌病原体具有提高功效的PUM类似物。将评估类似物的体外抑制RNAP，培养中的抗菌活性，对培养物中哺乳动物细胞的细胞毒性，培养中的抗性特性和物理特性。高希望的类似物将在小动物的感染模型中评估抗菌功效，并将评估具有最高诺言的类似物的生物利用度，药代动力学，安全性和扩展合成能力。