Inhibitors of poxvirus enzymes as novel drugs

抗痘病毒药物靶点是一个紧迫的问题，因为人们担心未申报的天花库存 可能被用作生物恐怖武器天花的根除是预防措施的胜利， 免疫接种后，天花的治疗从未超越支持疗法。其他治疗 人类痘病毒感染（传染性软疣、猴痘和免疫接种并发症） 牛痘病毒）也是非特异性的或不存在的。2004年爆发的人类猴痘感染 美国中西部在2003年强调了人类痘病毒病再次出现的风险。 我们的目标是通过阻断天花病毒的基因表达， 转录和加帽。我们将筛选LifePharms独特的专有图书馆， 从> 13，000野生蘑菇中提取物，以发现针对 包装在感染性病毒体核心内的mRNA转录装置。体外转录 透化病毒粒子的反应通常被认为忠实地再现了病毒早期感染的过程。 mRNA在宿主细胞中发生的生物合成。通过体外筛选抑制mRNA合成， 通过透化病毒体的处理，我们期望鉴定出阻断一种或多种 负责痘病毒早期mRNA转录和加帽的关键病毒酶。这一战略对于 初级筛选比针对单个病毒蛋白的筛选具有关键优势，因为：（i）它选择 对于能够接近病毒体核心内的靶标的化合物;和（ii）它包括多个 潜在的酶靶点。靶点包括：（i）DNA依赖性RNA 聚合酶;（ii）ETF（早期转录因子），DNA依赖性ATP酶;（iii）加帽酶RNA 三磷酸酶、RNA鸟苷酰转移酶和RNA鸟嘌呤-N7甲基转移酶;（iv）NPH 1，转录 具有DNA依赖性ATP酶活性的延伸/终止因子;（v）NPH 2，RNA解旋酶;和（vi） DNA拓扑异构酶。这些痘病毒酶是突出的药物靶标和这些酶的特异性抑制剂。 酶将为药物开发提供先导化合物，并为痘病毒的基础研究提供关键工具。 复制的 尽管真菌天然产物对药理学和药物发现做出了重大贡献， 所有真菌物种中只有一小部分被筛选出生物活性化合物。LifePharms图书馆 包含的物种多样性几乎相当于所有真菌物种检查以前。药物发现 这里的项目大纲合并了LifePharms，Inc.的互补专业知识。在真菌生态学和自然 产品提取物收购，斯图尔特舒曼博士在痘病毒酶学和分子生物学， 研究三角研究所在天然产物药物发现和药物化学。

Antipoxvirus drug targets are a pressing issue, given the concern that undeclared stocks of smallpox might be used as a bioterror weapon. Whereas the eradication of smallpox was a triumph of prophylactic immunization, the treatment of smallpox never advanced beyond supportive therapy. Treatments for other poxvirus infections of humans (molluscum contagiosum, monkeypox, and complications of immunization with vaccinia virus) are also either nonspecific or nonexistent. The outbreak of human monkeypox infections in the US Midwest in 2003 highlighted the risks of re,emergence of human poxvirus disease. Our goal is to identify novel drugs for the treatment and chemoprophylaxis of smallpox by blocking the transcription and capping of viral mRNAs. We will screen LifePharms' unique and proprietary library of extracts from >13,000 wild mushrooms to discover new inhibitors of poxvirus replication targeted to the mRNA transcription apparatus packaged within the core of the infectious virion. The in vitro transcription reaction of permeabilized virions is generally accepted to faithfully recapitulate the process of viral early mRNA biogenesis as it occurs in the host cell. By screening in vitro for inhibition of mRNA synthesis and processing by permeabilized virions, we expect to identify candidate antivirals that block one or more of the key viral enzymes responsible for transcription and capping of poxvirus early mRNAs. This strategy for primary screening has key advantages over screens against individual viral proteins because: (i) it selects for compounds that are capable of accessing the target within the virion core; and (ii) it embraces multiple potential enzymatic targets within a single assay platform. The targets include: (i) DNA-dependent RNA polymerase; (ii) ETF (early transcription factor), a DNA-dependent ATPase; (iii) the capping enzymes RNA triphosphatase, RNA guanylyltransferase and RNA guanine-N7 methyltransferase; (iv) NPH1, a transcription elongation/termination factor with DNA-dependent ATPase activity; (v) NPH2, an RNA helicase; and (vi) DNA topoisomerase. These poxvirus enzymes are outstanding drug targets and specific inhibitors of these enzymes will provide lead compounds for drug development as well as key tools for basic studies of poxvirus replication. Although fungal natural products has made major contributions to pharmacology and drug discovery, only a fraction of all fungal species have been screened for bioactive compounds. LifePharms' library contains species diversity nearly equivalent to all fungal species examined previously. The drug discovery project outline here merges the complementary expertise of LifePharms, Inc. in fungal ecology and natural product extract acquisition, Dr. Stewart Shuman in poxvirus enzymology and molecular biology, and Research Triangle Institute in natural product dru 9 discovery and medicinal chemistry.