ＳＣＰ２是一个３１ｋｂ的低拷贝链霉菌质粒，ＳＣＰ２＊作为ＳＣＰ２的天然突变体在载体的构建和应用方面得到了广泛的应用。与ＳＣＰ２相比，ＳＣＰ２＊诱动染色体的能力提高了约１０００倍，具有清晰的“麻点”形成特征并在接合时的供受体双方均携带有野生型ＳＣＰ２时没有“进入不利”的属性。通过缺失分析，已确定了与接合转移、麻点形成及质粒稳定性等功能区，对ＳＣＰ２＊的复制功能也进行了深入的研究。本文对ＳＣＰ２分子生物学研究和应用的进展进行系统综述。 SCP2 is a 31 kb low copy Streptomyces plasmid and SCP2 * is widely used as a natural mutant of SCP2 in the construction and application of vectors. Compared to SCP2, SCP2 * has an approximately 1,000-fold increase in the capacity to elicit chromosomes, has a clear “pock-forming” signature and does not have “inadvertent” attributes when both wild-type SCP2 are bound to the donor at the time of mating . Through deletion analysis, functional regions such as junctional transfer, pitting formation and plasmid stability have been identified, and the replication function of SCP2 * has also been studied in depth. This article systematically reviews the progress of research and application of SCP2 molecular biology.