Biochemical Strategy to Avert Microbial Drug Resistance

项目总结/摘要 这项研究的目的是开发一种可推广的抗菌策略 这可以避免抵抗的发生。所提出的抗病毒剂具有以下机制： 依赖于致病蛋白的功能而不是抑制作用的作用。 具体地，该试剂是人酶核糖核酸酶1的细胞毒性变体 （RNase 1），其被遮盖并且因此作为催化剂是无活性的。斗篷只有在 一种病原体生命周期所必需的病原性蛋白酶。SARS-CoV-2将 作为研究中的模式病原体。目标将通过以下方式实现：（1）确定 被SARS-CoV-2的3CLpro蛋白酶切割的最佳氨基酸序列， 而不是通过内源性人蛋白酶，（2）使用该序列和内含肽介导的顺式- 剪接以产生环状RNA酶1酶原，以及（3）证明了所述环状RNA酶1酶原的能力。 酶原杀死表达3CLpro并被感染的人肺细胞 SARS-CoV-2.因为激活的酶原也可以破坏RNA的基因组 像SARS-CoV-2这样的病毒，它可以根除患者体内的病毒储存库。一个显著特点 该策略的一个重要特点是其模块性：蛋白酶切割序列是一个可以 改变以匹配病原性蛋白酶的特异性，用于治疗其他 传染病

PROJECT SUMMARY/ABSTRACT The goal of the proposed research is to develop a generalizable antimicrobial strategy that averts the onset of resistance. The proposed antiviral agent has a mechanism of action that relies on the function of a pathogenic protein rather than its inhibition. Specifically, the agent is a cytotoxic variant of a human enzyme, ribonuclease 1 (RNase 1), that is cloaked and thus inactive as a catalyst. The cloak is removable only by a pathogenic protease that is essential for the lifecycle of the pathogen. SARS-CoV-2 will serve as a model pathogen in the study. The goal will be attained by (1) identifying an optimal amino acid sequence that is cleaved by the 3CLpro protease of SARS-CoV-2 but not by endogenous human proteases, (2) using that sequence and intein-mediated cis- splicing to create a cyclic RNase 1 zymogen, and (3) demonstrating the ability of the zymogen to kill human lung cells that express 3CLpro and that are infected by SARS-CoV-2. Because the activated zymogen can also destroy the genome of an RNA virus like SARS-CoV-2, it could eradicate the viral reservoir in patients. A notable feature of the strategy is its modularity: the protease-cleavage sequence is a cassette that can be altered to match the specificity of pathogenic proteases for the treatment of other infectious diseases.