Inhibitors of transcription of fungal glucan synthase

真菌葡聚糖合酶转录抑制剂

基本信息

批准号：
6688368
负责人：
Claude P Selitrennikoff
金额：
$ 10万
依托单位：
MYCOLOGICS, INC.
依托单位国家：
美国
项目类别：
财政年份：
2003
资助国家：
美国
起止时间：
2003-07-01 至 2004-12-30
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/6688368
关键词：
Candida albicans Cryptococcus neoformans antifungal agents cell wall cytotoxicity drug screening /evaluation fungal genetics genetic transcription green fluorescent proteins hexosyltransferase inhibitor /antagonist polymerase chain reaction tissue /cell culture

项目摘要

DESCRIPTION (provided by applicant): Perhaps the most striking difference between fungal cells and human cells is that fungal cells are encased in a wall that protects them from an osmotically and immunologically hostile external environment. In addition, the fungal cell wall relays signals for invasion and infection of a likely plant, animal, or human host. The cell wall is not an inert outer layer, but rather plays a dynamic role in all aspects of fungal physiology, e.g., morphogenesis, metabolite transport, protein secretion, intracellular signaling, and cell-cell contact. Cell-wall structure is now well characterized, at least in the ascomycetes, and appears to be very similar in human pathogens including Candida albicans, Penicillium spp., and Aspergillus spp. The fact that human cells lack a cell wall and the underlying biosynthetic and regulatory machinery to make the wall, suggests that drugs targeting cell-wall synthesis and assembly will be safe and specific antifungals. Current treatments for fungal infections are limited by few therapeutic options; these include amphotericin B, which interacts with membrane sterols, and a variety of azoles and allylamines that inhibit membrane sterol biosynthesis. Unfortunately, amphotericin B is toxic to humans and clinical resistance to azoles is increasing. These observations underscore the clear need for new antifungals. In this Phase I SBIR application, we propose to develop a novel screen that identifies inhibitors of transcription of a key gene for fungal cell-wall assembly, namely, the catalytic subunit of (1,3) beta-glucan synthase activity. This will be accomplished in two specific aims: Aim One: Development of a screen to identify inhibitors of transcription of the FKS gene encoding the catalytic subunit of (1,3) beta -glucan synthase. Aim Two: Screen 3,000 pure compounds for inhibitors of transcription of the (1,3) beta -glucan synthase FKS gene. Importantly, we will determine the effect of putative inhibitors on fungal growth, on human-cell toxicity, and on the levels of FKS message. This work will lead to a novel assay that will be used for the discovery of new antifungal compounds. In turn, these novel compounds will be developed for the treatment of human fungal diseases.

描述（由申请人提供）：真菌细胞和人类细胞之间最明显的差异是真菌细胞被包裹在保护它们免受渗透和免疫学上敌对的外部环境中的壁中。此外，真菌细胞壁传递了可能侵袭和感染可能植物，动物或人类宿主的信号。细胞壁不是惰性的外层，而是在真菌生理学的各个方面起动态作用，例如形态发生，代谢物转运，蛋白质分泌，细胞内信号传导和细胞细胞接触。现在至少在子囊菌中表征了细胞壁结构，并且在包括白色念珠菌，青霉属和曲霉属的人类病原体中似乎非常相似。人类细胞缺乏细胞壁以及制造壁的基本生物合成和调节机制，这一事实表明，靶向细胞壁合成和组装的药物将是安全的，特定的抗真菌剂。当前对真菌感染的治疗受到很少的治疗选择的限制。其中包括与膜固醇相互作用的两性霉素B，以及抑制膜固醇生物合成的各种尝试力的叠氮和烯丙基。不幸的是，两性霉素B对人类有毒，对硫唑则有抗性。这些观察结果强调了对新抗真菌剂的明显需求。在此阶段I SBIR应用中，我们建议开发一个新的屏幕，该屏幕鉴定了真菌细胞壁组装的关键基因转录的抑制剂，即（1,3）β-葡聚糖合酶活性的催化亚基。这将在两个具体目标中实现：目标一：开发筛选以鉴定编码（1,3）β-葡聚糖合酶催化亚基的FKS基因转录抑制剂。目标两个：筛网3,000纯化合物，用于（1,3）β-葡聚糖合酶FKS基因的转录抑制剂。重要的是，我们将确定推定抑制剂对真菌生长，人细胞毒性以及FKS信息水平的影响。这项工作将导致一种新颖的测定法，该测定法将用于发现新的抗真菌化合物。反过来，这些新型化合物将被开发用于治疗人类真菌疾病。