Innovative technologies to transform antibiotic discovery. Project 4 Infection site-specific amplification of antimicrobial conjugates

摘要 由于革兰氏阴性菌的耐药性迅速演变，临床上革兰氏阴性菌的药物治疗是一个迫切的未满足的需求。 菌株，常规抗生素无法穿透外细胞壁，以及体内药物毒性脱靶。 抗菌肽（AMP）和其他小分子抗菌先导物在临床前研究中显示出前景。 测试杀死多药耐药革兰氏阴性病原体，但在临床上面临重大挑战 由于体内较差的治疗结果而导致翻译。这一建议解决了小说的短缺问题。 通过利用病原体的细胞表面治疗多药耐药革兰氏阴性病原体的策略 聚糖和局部环境来递送抗微生物有效载荷。长循环的前药构建体将是 经工程改造，在全身给药后选择性靶向感染部位， 感染组织微环境特异性的蛋白水解活性。拟议的抗菌剂，称为 抗微生物缀合物（AMC）由病原体特异性靶向剂、微环境特异性靶向剂和微环境特异性靶向剂组成。 可裂解接头和杀菌有效负载。这种模块化设计允许探索不同的组件 以优化结合物的活性。拟定的AMC将在体外进行设计和广泛评价， 麻省理工学院的Sangeeta Bhatia博士组成的一个联合小组， Timothy Lu，Laura Kiessling，和布拉德利Pentelute.他们的实验室将利用蛋白酶反应的专业知识， 纳米材料，合成生物学和计算设计，蛋白质聚糖识别过程， 生物偶联技术和快速肽合成技术，以促进AMC的发展。 这种新的治疗方式具有几个优点：对病原体靶点的高水平特异性， 限制对宿主的毒性，使得能够使用选择性较低的抗微生物剂，缀合物将增加 药代动力学，窄谱活性将避免一般耐药机制的传播 并限制对宿主微生物群的损害。项目完成后将产生铅 用于治疗抗性革兰氏阴性感染的抗微生物缀合物。共同优化 先导化合物的治疗特性将确定可用于临床前试验的最佳候选物， 具有提供有效绕过获得性革兰氏阴性抗生素的治疗策略的潜力 阻力

ABSTRACT Drugging Gram-negative bacteria in the clinic is an urgent unmet need due to rapidly-evolving resistant strains, the inability of conventional antibiotics to penetrate the outer cell wall, and off-target in vivo drug toxicities. Antimicrobial peptides (AMPs) and other small molecule antibacterial leads have shown promise in preclinical testing for killing multi-drug resistant Gram-negative pathogens, but have faced significant challenges in clinical translation as a result of inferior therapeutic outcomes in vivo. This proposal addresses the shortage of novel treatment strategies for multi-drug resistant Gram-negative pathogens by exploiting the pathogen's cell surface glycans and local environment to deliver antimicrobial payloads. Long-circulating, pro-drug constructs will be engineered that selectively target the site of infection after systemic administration and activate in response to proteolytic activity specific to the infected tissue microenvironment. The proposed antimicrobial agents, termed antimicrobial conjugates (AMCs) consist of a pathogen-specific targeting agent, a microenvironment-specific cleavable linker, and a bactericidal payload. This modular design allows the exploration of different components to optimize the conjugate's activity. The proposed AMCs will be designed and extensively evaluated in vitro and in animal models for toxicity and antimicrobial activity by a joint team at MIT composed of Drs. Sangeeta Bhatia, Timothy Lu, Laura Kiessling, and Bradley Pentelute. Their labs will leverage expertise with protease-responsive nanomaterials, synthetic biology and computational design, protein-glycan recognition processes, and bioconjugation and rapid peptide synthesis technologies, respectively, to advance the development of AMCs. This new therapeutic modality has several advantages: the high level of specificity for pathogen targets will limit toxicity to host, enabling the use of less selective antimicrobial agents, the conjugates will have increased pharmacokinetics, and the narrow spectrum activity will avoid the spread of general resistance mechanisms between species and limit damage to the host microbiota. Completion of the project will generate lead antimicrobial conjugates for the treatment of resistant Gram-negative infections. Collectively optimizing the therapeutic profiles of lead compounds will identify top candidates that can be advanced for pre-clinical trials, with the potential to deliver a therapeutic strategy that effectively bypasses acquired Gram-negative antibiotic resistance.