Enediyne Antitumor Antibiotic Synthesis - Streptomycetes

描述(申请人提供)：烯二炔类抗生素是最有效的， 当今存在的高活性抗肿瘤药物。新卡氮平(NCS)和 其结合物在抗癌化疗中显示出巨大的临床应用前景， 以及几种Calicheamicin抗体和C-1027抗体的结合物 在最近的临床试验或模型研究中取得了突出的结果。 因此，开发方法使其成为一个重要的研究目标。 烯二炔类化合物及其类似物以供进一步研究。此应用程序建议 链霉菌NCS产生相关基因的克隆与鉴定 Carzinostaticus，补充我们在链霉菌中对C-1027的持续努力 球孢子菌，试图通过操纵合成新型抗肿瘤药物 控制烯二炔抗生素生物合成的基因。这项建议是基于 NCS发色团来源于三种生物合成的假说 构筑了烯二炔核、脱氧氨基糖和聚酮 环烷酸部分。这一假设的三个推论是：(1) 广泛了解放线菌中脱氧糖和聚酮的生物合成 应该大大有助于克隆脱氧氨基糖和 从猪链霉菌中生物合成萘甲酸，(2)结构 NCS和C-1027的烯二炔核之间的相似性提供了一个独特的 破译烯二炔核心的遗传和生化基础的机会 以及(3)基因工具和技术是在 用于抗生素生物合成的链霉菌应直接适用 操纵NCS和C-1027生物合成基因以提高产量和 模拟或新颖的烯二炔生产。五年奖的具体目标 时间段为(1)克隆和测序整个NCS生物合成基因簇 (2)建立链球藻遗传系统。 Carzinostaticus在体内操纵NCS生物合成，(3)确认 克隆编码NCS生物合成的卡氏链球菌DNA并定位 NCS基因簇的基因破坏和替换的边界 实验，以及(4)确定烯二炔核心所必需的基因 通过比较NCS和C-1027生物合成基因簇和To进行生物合成 通过表达二烯二炔核结构来演示其合成 异源宿主中的相应基因。这些研究的结果将 揭示了对烯二炔家族生物合成的新见解 抗生素，揭示烯二炔生物合成的合理工程 在这些以及其他产生二炔的有机体中，并可能 现实地导致了从根本上说是新的、临床上有用的 抗肿瘤药物

DESCRIPTION (provided by applicant): Enediyne antibiotics are the most potent, highly active antitumor agents in existence today. Neocarzinostatin (NCS) and its conjugates have shown great clinical promise in anticancer chemotherapy, and several calicheamicin-antibody and C-1027-antibody conjugates have produced outstanding results in recent clinical trials or model studies. Therefore, it is a critical research goal to develop ways to make the enediynes and their analogs for further studies. This application proposes to clone and characterize the genes for NCS production in Streptomyces carzinostaticus, complementing our on going effort for C-1027 in Streptomyces globisporus, in an attempt to synthesize novel antitumor drugs by manipulating genes governing enediyne antibiotic biosynthesis. This proposal is based on the hypothesis that the NCS chromophore is derived from three biosynthetic building blocks an enediyne core, a deoxy aminosugar, and a polyketide naphthoic acid moiety. Three corollaries of this hypothesis are (1) that the extensive knowledge of deoxysugar and polyketide biosynthesis in actinomycetes should greatly aid the effort to clone the genes for deoxy aminosugar and naphthoic acid biosynthesis from S. carzinostaticus, (2) that the structural similarity between the enediyne cores of NCS and C-1027 provides an unique opportunity to decipher the genetic and biochemical basis of enediyne core assembly, and (3) that the genetic tools and technology developed in Streptomyces species for antibiotic biosynthesis should be directly applicable to manipulating NCS and C-1027 biosynthesis genes for yield improvement and analog or novel enediyne production. The specific aims for the five-year award period are (1) to clone and sequence the entire NCS biosynthetic gene cluster from S. carzinostaticus, (2) to develop a genetic system for S. carzinostaticus to manipulate NCS biosynthesis in viva, (3) to confirm the cloned S. carzinostaticus DNA encoding NCS biosynthesis and to localize the boundaries of the NCS gene cluster by gene disruption and replacement experiments, and (4) to identify genes essential for the enediyne core biosynthesis by comparing the NCS and C-1027 biosynthetic gene clusters and to demonstrate the synthesis of an enediyne core structure by expressing the corresponding genes in a heterologous host. The outcome of these studies will reveal new insights into the biosynthesis of the enediyne family of antibiotics, shedding light on rational engineering of enediyne biosynthesis in these as well as other enediyne-producing organisms, and could realistically lead to the making of fundamentally new, clinically useful antitumor agents