Novel Antifungals by Engineering the AbA NRPS gene

描述（由申请人提供）：目前迫切需要有效的新型抗真菌药物。真菌出芽短梗霉（Aureobasidium pullulans）产生称为短梗霉素A（阿坝）的环肽，其是非常有效的杀真菌药物，由于需要涉及复杂且昂贵的合成化学的修饰，目前被禁止商业化。本申请中描述的项目的总体目标是（遗传地）工程化A。通过不使用合成化学或仅限于单一取代的合成化学，将普鲁兰多糖转化为环肽，以产生或可以开发成耐受性良好、有效、广谱的抗真菌药物。该项目的第一阶段涉及编码非核糖体肽合成酶（NRPS）复合物的基因的鉴定、克隆、测序和作图，该复合物负责阿坝A.普鲁兰多糖。完整NRPS基因序列的测定将允许鉴定和定位复合物中的生物合成模块和结构域，从而阐明天然化合物的组装序列。这些信息与克隆的基因一起将提供进行第二阶段研究计划所需的工具。第二阶段将涉及通过修饰或转换生物合成模块和结构域来改变天然NRPS复合物基因，从而产生能够产生新的环肽的生物体，所述新的环肽需要最少的化学反应来成为有效的广谱抗真菌药物。

DESCRIPTION (provided by applicant): There is an immediate need for efficient, novel antifungal drugs. The fungus Aureobasidium pullulans produces a cyclic peptide know as Aureobasidin A (AbA) which is a very potent, fungicidal drug that is currently barred from commercialization due to a requirement for modifications involving complex and expensive synthetic chemistry. The overall goal of the project described in this application is to (genetically) engineer A. pullulans to produce cyclic peptides that are, or can be developed into, well-tolerated, potent, broad spectrum antifungal drugs, using no synthetic chemistry or synthetic chemistry limited to a single substitution. Phase I of the project involves the identification, cloning, sequencing and mapping of the gene encoding the non-ribosomal peptide synthetase (NRPS) complex responsible for the synthesis of native AbA in A. pullulans. Determination of the complete NRPS gene sequence will allow identification and mapping of the biosynthetic modules and domains in the complex and thereby elucidation of the assembly sequence of the native compound. This information together with the cloned gene will provide the tools required to carry out the Phase II research plan. Phase II will involve altering the native NRPS complex gene by modifying or switching the biosynthetic modules and domains thereby generating organisms capable of producing novel cyclic peptides requiring minimal chemistry to become potent broad-spectrum antifungal drugs.