Novel Antifungals by Engineering the AbA NRPS gene

通过改造 AbA NRPS 基因开发新型抗真菌药物

基本信息

批准号：
8115541
负责人：
Ake P Elhammer
金额：
$ 24.06万
依托单位：
AUREOGEN BIOSCIENCES, INC.
依托单位国家：
美国
项目类别：
财政年份：
2004
资助国家：
美国
起止时间：
2004-09-30 至 2013-01-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/8115541
关键词：
Address Agreement Amino Acids Amphotericin B Anabolism Anidulafungin Animals Antifungal Agents Aspergillus Azoles Bacteria Bacterial Genes Biological Factors Candida Caspofungin Cells Chemistry Clinical Code Complex Cryptococcus Cyclic Peptides DNA Data Development Down-Regulation Drug Interactions Engineered Gene Engineering Equipment and supply inventories Evaluation Event Gene Expression Generations Genes Genetic Genetic Engineering Genetic Transcription Goals Human In Vitro Industrial fungicide Itraconazole Ketoconazole Knock-in Mouse Legal patent Maps Marketing Messenger RNA Methodology Micafungin Modification Multienzyme Complexes Mycoses Nystatin Organ Transplantation Organism Patients Peptides Pharmaceutical Preparations Phase Plasmids Polyenes Positioning Attribute Preparation Production Property Protocols documentation Publications Publishing Regulation Reporting Resistance Reverse Transcription Sarcosine Science Source Specificity Structure Synthesis Chemistry Technology Therapeutic Toxic effect Transcript Translations Voriconazole Work aureobasidin A cancer transplantation commercialization cost drug candidate fungus homologous recombination improved non-ribosomal peptide synthase novel pathogen patient population peptide synthase promoter pullulan research study tool

项目摘要

DESCRIPTION (provided by applicant): The continuing increase in the number of surgery, transplantation, cancer and other immunocompromized patients, that need treatment for fungal infections, together with the fact that only one new class of antifungal therapeutics has been introduced to the market in over 30 years has created an immediate need for new and better antifungal drugs with novel modes of action (MoA). The natural product compound Aureobasidin A (AbA) is a potent, fungicidal drug with a novel MoA that also does not elicit resistant pathogen strains. Unfortunately, although efficacious and very well tolerated, native AbA's target spectrum is too narrow to be clinically attractive. Of the two major human pathogens, Candida spp. and Aspergillus spp., AbA only has efficacy against Candida. However, exploratory synthetic chemistry work has demonstrated that structural modifications can convert native AbA into compounds that have close to equal efficacy against both pathogens. The required chemistry, however, is complicated and expensive, to the extent that it constitutes a barrier against development of these compounds into commercial products. The overall goal of the project outlined in this proposal is to use a novel genetic engineering approach to introduce the structural modifications required to confer Aspergillus spp. activity to AbA, thereby avoiding the high cost of synthetic chemistry and allow commercialization of an efficacious, well tolerated antifungal drug with a novel MoA. In Phase I, the gene, aba 1, encoding the non-ribosomal peptide synthetase (NRPS) complex responsible for synthesis of AbA in the producer organism was identified, cloned, sequenced and mapped. Phase II has to date produced methodologies and a set of genetic tools that allow efficient engineering of the aba 1 gene. Also accomplished to date is the successful engineering of the aba 1 gene, the generation of engineered strains producing structurally modified AbA molecules and the generation of significant new data on the unique properties of fungal NRPS complexes. Production of structurally altered cyclic peptides by engineering of a fungal NRPS complex has not been reported previously. The project has to date produced two publications, one issued patent and one pending patent application. The continued Phase II work will involve engineering of the specific modifications required to confer Aspergillus spp. activity to AbA and the preparation/selection of a producer strain capable of high production levels. Successful completion of the project will: [1] provide an efficient, well-tolerated drug to a market with a strong demand for new products; [2] address a very immediate need from a growing patient population which currently have very few treatment options; and [3] provide proof of concept and critical tools for a novel and potentially very powerful approach to the discovery of new and improved therapeutics. PUBLIC HEALTH RELEVANCE: The continuing increase in the number of surgery, transplantation, cancer and other immunocompromized patients, that need treatment for fungal infections, has generated an immediate unmet need for new antifungal drugs with novel modes of action. The proposed project will add a potent, efficacious, well-tolerated and economical drug to an inventory of antifungal drugs that currently is both limited and associated with significant limitations.

描述（由申请人提供）：需要治疗真菌感染的手术、移植、癌症和其他免疫功能低下患者的数量不断增加，而且事实上，仅一种新的抗真菌疗法已被引入市场30 多年来，人们迫切需要具有新颖作用方式 (MoA) 的新型、更好的抗真菌药物。天然产物化合物 Aureobasidin A (AbA) 是一种有效的杀菌药物，具有新型 MoA，且不会引起耐药病原体菌株。不幸的是，尽管天然 AbA 有效且耐受性良好，但其靶标谱太窄，在临床上缺乏吸引力。在两种主要的人类病原体中，念珠菌属。和曲霉菌属中，AbA 仅对念珠菌有效。然而，探索性合成化学工作表明，结构修饰可以将天然 AbA 转化为对两种病原体具有接近相同功效的化合物。然而，所需的化学过程复杂且昂贵，以至于它构成了这些化合物开发成商业产品的障碍。该提案中概述的项目的总体目标是使用一种新颖的基因工程方法来引入赋予曲霉菌属所需的结构修饰。 AbA 的活性，从而避免合成化学的高成本，并允许具有新型 MoA 的有效、耐受性良好的抗真菌药物商业化。在第一阶段，编码非核糖体肽合成酶 (NRPS) 复合物的基因 aba 1 被鉴定、克隆、测序和定位，该复合物负责生产生物体中 AbA 的合成。迄今为止，第二阶段已经产生了方法和一套遗传工具，可以对 aba 1 基因进行有效的工程改造。迄今为止还完成了 aba 1 基因的成功工程改造、产生结构修饰的 AbA 分子的工程菌株的产生以及关于真菌 NRPS 复合物独特性质的重要新数据的产生。通过工程化真菌 NRPS 复合物生产结构改变的环肽此前尚未有报道。迄今为止，该项目已出版两份出版物，一份已颁发专利，一份正在申请专利。后续的第二阶段工作将涉及赋予曲霉菌属所需的特定修饰工程。 AbA 的活性以及能够高生产水平的生产菌株的制备/选择。该项目的成功完成将： [1] 为新产品需求旺盛的市场提供高效、耐受性良好的药物； [2] 满足不断增长的患者群体的迫切需求，而目前治疗选择很少； [3]为发现新的和改进的疗法的新颖且可能非常强大的方法提供概念证明和关键工具。公共卫生相关性：需要真菌感染治疗的手术、移植、癌症和其他免疫功能低下患者数量的持续增加，导致对具有新作用方式的新型抗真菌药物的迫切需求尚未得到满足。拟议的项目将为目前数量有限且存在重大局限性的抗真菌药物库存添加一种强效、有效、耐受性良好且经济的药物。