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从链霉菌ＦＲ－００８中克隆出一个七烯大环内酯抗生素的生物合成基因簇，基因置换试验证实克隆的基因片段与抗生素生物合成直接相关。ＦＲ－００８抗生素含有一个３８员由聚酮所衍生的内酯大环，由编码红霉素聚酮合酶的活性域基因片段为探针所进行的Ｓｏｕｔｈｅｒｎ杂交试验证明，链霉菌ＦＲ－００８的聚酮合酶（ＰＫＳ）的基因簇占据１０５ｋｂ连续和具有重复功能单元（模块）的序列；假设每个ＰＫＳ模块为５ｋｂ，这与ＦＲ－００８碳链形成需要２１个缩合过程的预期数值极其吻合。链霉菌ＦＲ－００８的基因克隆系统（包括转化、转座、从大肠杆菌向链霉菌的属间接合转移、基因置换和基因中断体系和限制性缺陷菌株）均已得到发展，使我们能够充分利用基因工程技术来操纵七烯大环内酯的生物合成并产生新的抗生素衍生物。同时利用该基因簇中的部分ＰＫＳ基因序列构建了一个可用于转化植物的质粒ｐＨＺ３２１，为尝试在水稻等植物中表达链霉菌Ⅰ型ＰＫＳ基因以探索高Ｇ十Ｃ（７６％）含量的链霉菌ＰＫＳ基因能否在植物中表达提供了材料和工具。用此质粒来转化植物的研究，将为进一步利用这个巨大的抗真菌抗生素基因簇进行植物抗真菌的基因工程育种提供理论依据。
A Streptomyces FR-008 cloned a hepcidin macrolide antibiotic biosynthetic gene cluster, gene replacement test confirmed that the cloned gene fragments and antibiotics is directly related to the biosynthesis. The FR-008 antibiotic contains a 38-member lactone macrocycle derived from a polyketide. Southern blotting with a probe encoding the active domain gene encoding erythromycin polyketide synthase demonstrated that Streptomyces sp. FR-008 The gene cluster of polyketide synthase (PKS) occupies a sequence of 105 kb contiguous and has repeating functional units (modules); assuming 5 kb per PKS module, this closely matches the expectation that FR-008 carbon chains require 21 condensation processes . The gene cloning system of Streptomyces FR-008 (including transformation, transposition, intergenic transfer from Escherichia coli to Streptomyces, gene replacement and gene disruption systems and restriction-deficient strains) has been developed that allows us to make full use of Genetic engineering techniques manipulate the biosynthesis of heptacene macrolides and generate new antibiotic derivatives. At the same time, a partial pKS gene sequence in this gene cluster was used to construct a plasmid pHZ321 which can be used for transforming plants. In order to explore the expression of Streptomyces type Ⅰ PKS gene in plants such as rice to explore the high G C (76%) content of Streptomyces The availability of materials and tools for PKS gene expression in plants. The study of transformation of plants with this plasmid will provide the theoretical basis for the further use of this huge antifungal antibiotic gene cluster for plant antifungal genetic engineering breeding.